Toxoplasma gondii(T.gondii)is a globally distributed parasite that can infect a diversity of warm-blooded animals,including swine and humans.Infection in swine poses a considerable threat to food safety and public hea...Toxoplasma gondii(T.gondii)is a globally distributed parasite that can infect a diversity of warm-blooded animals,including swine and humans.Infection in swine poses a considerable threat to food safety and public health.The aim of this meta-analysis was to estimate the seroprevalence of T.gondii infection in the swine population in China from 2000 to 2023 and to examine potential factors associated with infection.A total of 112 studies were included,collectively involving 145,152 swine samples originating from 26 provinces.The pooled seroprevalence was 26.0%(95%CI:23.3%–28.7%).Stratified analysis based on diagnostic methods revealed that studies using the indirect hemagglutination assay(IHA)reported a seroprevalence of 19.7%(95%CI:17.2%–22.2%),whereas those utilizing the enzyme-linked immunosorbent assay(ELISA)reported a higher seroprevalence of 35.5%(95%CI:29.1%–41.8%).Geographical analysis indicated higher seroprevalence in the South Central and Southwest regions,whereas the East and Northwest areas reported the lowest seroprevalence.Chongqing Province reported the highest seroprevalence,reaching 44.9%(95%CI:43.4%–46.0%),followed by Xinjiang,Hainan,and Guizhou,whereas the lowest was observed in Shandong Province(3.5%,95%CI:1.7%–6.1%).These findings provide important epidemiological evidence that can inform strategies for the prevention and control of T.gondii infection in swine populations,with a focus on high-risk populations and geographical areas.This imperative contributes substantially to the improvement of both food safety and public health.展开更多
Infectious diseases caused by arboviruses are a public health concern in Pakistan.However,studies on data prevalence and threats posed by arboviruses are limited.This study investigated the seroprevalence of arbovirus...Infectious diseases caused by arboviruses are a public health concern in Pakistan.However,studies on data prevalence and threats posed by arboviruses are limited.This study investigated the seroprevalence of arboviruses in a healthy population in Pakistan,including severe fever with thrombocytopenia syndrome virus(SFTSV),Crimean-Congo hemorrhagic fever virus(CCHFV),Tamdy virus(TAMV),and Karshi virus(KSIV)based on a newly established luciferase immunoprecipitation system(LIPS)assays,and Zika virus(ZIKV)by enzyme-linked immunosorbent assays(ELISA).Neutralizing activities against these arboviruses were further examined from the antibody positive samples.The results showed that the seroprevalence of SFTSV,CCHFV,TAMV,KSIV,and ZIKV was 17.37%,7.58%,4.41%,1.10%,and 6.48%,respectively,and neutralizing to SFTSV(1.79%),CCHFV(2.62%),and ZIKV(0.69%)were identified,as well as to the SFTSV-related Guertu virus(GTV,0.83%).Risk factors associated with the incidence of exposure and levels of antibody response were analyzed.Moreover,co-exposure to different arboviruses was demonstrated,as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing activity.Males,individuals aged40 years,and outdoor workers had a high risk of exposure to arboviruses.All these results reveal the substantial risks of infection with arboviruses in Pakistan,and indicate the threat from co-exposure to multiple arboviruses.The findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.展开更多
In Zanzibar, from the start of the pandemic in March 2020 to the time of sampling in December 2020, SARS-CoV-2 seroprevalence data was limited. We conducted a seroprevalence study to evaluate the magnitude of SARS-CoV...In Zanzibar, from the start of the pandemic in March 2020 to the time of sampling in December 2020, SARS-CoV-2 seroprevalence data was limited. We conducted a seroprevalence study to evaluate the magnitude of SARS-CoV-2 exposure among healthcare workers, school children, and people who attended general markets in Zanzibar. The objectives of the study were to analyse the total antibodies from selected higher-risk population groups in order to determine magnitude in SARS CoV-2 exposure. Blood samples were collected from eligible and consented participants (adults and children), and their serum was analyzed for total antibodies against SARS-CoV-2 using ELISA. A questionnaire was used to collect participants’ demographic and clinical data. The overall SARS-CoV-2 seroprevalence across all age groups was 33%, and a higher seroprevalence was observed in the 40 - 49 years’ age group relative to other ages as well as in those who attended markets. A runny nose (18.8% of participants) was the most frequently reported SARS-CoV-2 infection-related symptom. Multivariable analysis showed significantly higher odds of infection in people living in urban districts. The findings provide insight into SARS-CoV-2 infection among school children, health workers, and people who attended markets in Zanzibar in the early stages of the pandemic. Exposure in these groups might have been influenced by infection and prevention strategies taken by the government, as well as shopping behavior, school overcrowding, and population density in urban settings. The study had methodological limitations, including cross-sectional design. Further, well-designed, longitudinal studies are recommended to understand exposure and transmission at a population level.展开更多
Blood transfusion saves lives and reduces morbidity and mortality for a large number of diseases and clinical conditions, but it is not without danger. The aim of this study was to determine the seroprevalence of HIV ...Blood transfusion saves lives and reduces morbidity and mortality for a large number of diseases and clinical conditions, but it is not without danger. The aim of this study was to determine the seroprevalence of HIV and hepatitis B in blood donors received at the regional Blood Transfusion Centre of N’Zérékoré (Guinea). This was a 5-year retrospective analytical study. We included records of blood donors aged 18 to 60 years admitted to the N’Zérékoré Regional Blood Transfusion Centre for blood donation from January 2016 to December 2020. We performed a descriptive analysis followed by Chi-2 or Fish-er-exact tests and the Student or Wilcoxon test, followed by multivariate logistic regression. In this study, donor age ranged from 18 - 60 years, with a pre-dominance of donors aged 25 - 34 (44.2%). Male donors were the most represented in our study (79.0% versus 21.0% female). More than half of the donors were blood group O (55.6%). We observed a seroprevalence of 3.6% for HIV, 13.4% for HBsAg and 0.2% for co-infection. In our series, age 25 - 34 (OR = 1.89 and P = 0.001) and 35 - 44 for HIV (OR = 2.01 and P = 0.001), HBsAgserostatus (OR = 3.04 and P = 0.001) and blood donation history (OR of 3.04 and P = 0.001) were factors associated with HIV positivity (P < 0.05). In our study, HIV serostatus (OR = 3.04 and P = 0.001) and blood donation history (OR = 0.01 and P = 0.001) were factors associated with HBsAgseropositivity. We reported a high prevalence of HIV and HBsAg. Sex, serological status and blood donation history were associated factors.展开更多
Human adenoviruses(HAdVs) commonly cause many diseases such as respiratory diseases, gastroenteritis, cystitis worldwide. HAdV-3,-7,-4 and emergent HAdV-55 and HAdV-14 are the most important types causing severe respi...Human adenoviruses(HAdVs) commonly cause many diseases such as respiratory diseases, gastroenteritis, cystitis worldwide. HAdV-3,-7,-4 and emergent HAdV-55 and HAdV-14 are the most important types causing severe respiratory diseases. There is no effective drug available for clinical treatment, and no vaccine available for the general population.Therefore, it is important to investigate the seroprevalence against HAdV for developing novel vaccines and vectors. In this study, we investigated the seroprevalence and titer levels of neutralizing antibodies(NAb) against HAdV-3,-4,-7,-14,-55,and-11 in total 278 healthy populations between 0 months and 49 years of age(228 children and 50 adults) from Guangzhou. In children under the age of 18 years, the seropositive rates were significantly increased against HAdV-3 at12.07%, 33.96%, and 64.29% and against HAdV-7 at 0%, 18.87%, and 19.05% in age groups of 1–2, 3–5, and 6–17 years,respectively. The seroprevalence was very low(0% - 8.1%) for all other four types. In adults aged between 18 and49 years, HAdV-3,-4, and-7(> 50.00%) were the most common types, followed by HAdV-14(38.00%),-55(34.00%),and-11(24.00%). Adults tended to have high NAb titers against HAdV-4 and-55. HAdV-55-seropositive donors tended to be HAdV-11-and HAdV-14-seropositive. These results indicated the low level of herd immunity against all six HAdV types in young children, and HAdV-14,-55,-11 in adults from Guangzhou City. Our findings demonstrate the importance of monitoring HAdV types and developing vaccines against HAdV for children and adults.展开更多
Serum samples were tested for Bartonella henselae Ig G antibodies using indirect immunofluorescence assays.We then analyzed associated risk factors.Serum samples were considered positive when reactive at a dilution of...Serum samples were tested for Bartonella henselae Ig G antibodies using indirect immunofluorescence assays.We then analyzed associated risk factors.Serum samples were considered positive when reactive at a dilution of more than 1:320.展开更多
The incidence of Japanese encephalitis(JE)has significantly decreased in China due to JE vaccines.In this study,we investigated the post-JE vaccination seroprevalence and protection provided by vaccinated sera against...The incidence of Japanese encephalitis(JE)has significantly decreased in China due to JE vaccines.In this study,we investigated the post-JE vaccination seroprevalence and protection provided by vaccinated sera against Japanese encephalitis virus(JEV)to elucidate the persistence and waning of antibodies to JEV among JE-SA14-14-2-vaccinated children.A total of 300 serum samples were collected from vaccinated children aged 3-10 years in Zhaotong,Yunnan,China.The seroprevalence of anti-JEV antibodies was determined by enzyme-linked immune sorbent assay and plaque reduction neutralization test.The highest seropositivity of 82%was observed in vaccinated children during the first 0.5-1.5 years after booster vaccination.Then,the seropositivity began to decline and remained lower than the original level observed in the 0.5-1.5-year group.An association was found between the waning of seroprevalence and elapsed time of the post-booster vaccination.Similarly,the neutralizing antibody(nAb)titres gradually decreased over time,and the levels showed a positive correlation with the protective efficacy in mice.This finding suggests that nAbs play an important role in the antiviral process and that the nAb titre is an adequately credible parameter for evaluating the protective efficacy induced by the JE vaccine.Our results provide data that clarify the persistence and waning of antibodies to JEV,which may help elucidate the pathogenesis of JE.展开更多
Objective:To determine the seroprevalence of toxoplasmosis in pregnant women,as well as the proportion of acutely infected and risk factors in the Democratic Republic of Congo.Methods:Thirty maternities in Kinshasa we...Objective:To determine the seroprevalence of toxoplasmosis in pregnant women,as well as the proportion of acutely infected and risk factors in the Democratic Republic of Congo.Methods:Thirty maternities in Kinshasa were randomly selected and women attending antenatal consultation were invited to participate.They were interviewed with a structured questionnaire about known risk factors(age,meat consumption,contact with soil,and presence of cat)and a venous blood sample was taken.Sera were analysed for total immunoglobulins(Ig)by VIDAS Toxo Competition using Enzyme Linked Fluorescent Assay.IgM was determined by VIDIA Toxo IgM and IgG avidity by VIDAS Toxo IgG avidity.Results:A total of 781 women were included.Median age was 28 years old(IQR:8.S).And 627women(80.3%;95%CI:77.5-83.1)were found to be positive to total Ig and 17 out of 387(4.4%;95%CI:2.3-6.4)were positive to IgM.IgC avidity was low for 2(11.8%)women,intermediate for 2(11.8%)and high for 13 women(76.4%).There was no statistically significant association between Toxoplasma gondii infection and any risk factors assessed.Conclusion:In Kinshasa,toxoplasmosis endemicity is highly prevalent.One woman out of twenty five had a recent toxoplasmosis infection and 20%were not protected against primoinfection,indicating a need for measures to prevent and control toxoplasmosis during pregnancy.展开更多
Objective:To report our experience with two tests,anti-cardiolipin antibody test[venereal disease reasearch laboratory(VDRL) test]and specific treponemal test(Treponema pallidum hemagglutination assay),used for screen...Objective:To report our experience with two tests,anti-cardiolipin antibody test[venereal disease reasearch laboratory(VDRL) test]and specific treponemal test(Treponema pallidum hemagglutination assay),used for screening antenatal,high risk cases and cases from sexually transmitted infection in a tertiary care hospital from January 2006 till December 2008.Methods:A total of 14639 samples received from various patient groups including antenatal cases,patients attending sexually transmitted disease(STD) clinic,blood donors and HIV positive patients were screened.Results:Among the 14639 samples collected,103 were positive by VDRL test.Of these 89 cases were confirmed by quantitative VDRL test and Treponema pallidum hemagglutination assay.The cumulative seroprevalence over two years was found to be 0.61%in this study.The syphilis seroprevalence reduced from 0.88%in 2006 to 0.40%in 2008.Among the various sub-populations studied,patients attending the sexually transmitted infection clinic showed a seroprevalence of 2.62%.The seroprevalence decreased significantly from 4.00%in 2006 to1.39%in 2008.Conclusions:Our study showed a statistically significant declining rate of syphilis in STD clinics as well as the overall seroprevalence.These findings could be interpreted as indicators of improved programmes for prevention and management of STDs.展开更多
AIMTo determine the seroprevalence of hepatitis B surface antigen (HBsAg) among pregnant women attending antenatal clinic in Honiara, Solomon Islands. METHODSThis descriptive cross-sectional study was carried out in s...AIMTo determine the seroprevalence of hepatitis B surface antigen (HBsAg) among pregnant women attending antenatal clinic in Honiara, Solomon Islands. METHODSThis descriptive cross-sectional study was carried out in seven area health centers in Honiara. From March to June 2015, identification of eligible pregnant women in each site was conducted using systematic random sampling technique. A total of 243 pregnant women who gave written informed consent were enrolled. Standardized tool was used to record demographics, obstetric history and serology results. HBsAg and hepatitis B e antigen (HBeAg) were tested using point-of-care rapid diagnostic test. All HBsAg positive samples were verified using enzyme-linked immunosorbent assay. RESULTSThe mean age of participants was 26 ± 6 years. The overall hepatitis HBsAg prevalence was 13.8% with higher rate (22%) reported in women between 30-34 years of age. Majority of HBsAg positive participants were Melanesians (29 out for 33). None of the pregnant women in the 15-19 years and ≥ 40 years tested positive for HBsAg. There was no statistically significant difference in HBsAg prevalence by age, ethnicity, education and residential location. The overall HBeAg seroprevalence was 36.7%. Women between 20-24 years of age had the highest rate of 54.5%. Low level of knowledge about hepatitis B vaccination was reputed. Overall, 54.6% of participants were not aware of their hepatitis B vaccination status and only 65.2% of mothers reported their child had been vaccinated. CONCLUSIONHepatitis B is a disease of public health importance in Solomon Islands and emphasize the need for integrated preventative interventions for its control.展开更多
Human adenoviruses type 26(HAdV26)and type 35(HAdV35)have increasingly become the choice of adenovirus vectors for vaccine application.However,the population pre-existing immunity to these two adenoviruses in China,wh...Human adenoviruses type 26(HAdV26)and type 35(HAdV35)have increasingly become the choice of adenovirus vectors for vaccine application.However,the population pre-existing immunity to these two adenoviruses in China,which may reduce vaccine efficacy,remains largely unknown.Here,we established micro-neutralizing(MN)assays to investigate the seroprevalence of neutralizing antibodies(nAbs)against HAdV26 and HAdV35 in the general population of Guangdong and Shandong provinces,China.A total of 1184 serum samples were collected,47.0%and 15.8%of which showed HAdV26 and HAdV35 nAb activity,respectively.HAdV26-seropositive individuals tended to have more moderate nAbs titers(201-1000),while HAdV35-seropositive individuals appeared to have more low nAbs titers(72-200).The seropositive rates of HAdV26 and HAdV35 in individuals younger than 20 years old were very low.The seropositive rates of HAdV26 increased with age before 70 years old and decreased thereafter,while HAdV35 seropositive rates did not show similar characteristics.Notably,the seropositive rates and nAb levels of both HAdV26 and HAdV35 were higher in Guangdong Province than in Shandong Province,but did not exert significant differences between males and females.The seroprevalence between HAdV26 and HAdV35 showed little correlation,and no significant cross-neutralizing activity was detected.These results clarified the characteristics of the herd immunity against HAdV26 and HAdV35,and provided information for the rational development and application of HAdV26 and HAdV35 as vaccine vectors in China.展开更多
Severe fever with thrombocytopenia syndrome phlebovirus(SFTSV)has a wide host range.Not only has it been found in humans,but also in many wild and domesticated animals.The infection of breeding deer on farms is a part...Severe fever with thrombocytopenia syndrome phlebovirus(SFTSV)has a wide host range.Not only has it been found in humans,but also in many wild and domesticated animals.The infection of breeding deer on farms is a particularly worrisome public health concern due to the large amount of human contact and the diverse use of deer products,including raw blood.To investigate the prevalence of breeding domesticated deer,we examined the SFTSV infection rate on deer farms in South Korea from 2015 to 2017.Of the 215 collected blood samples,0.9%(2/215)were found to be positive for viral RNA by PCR,and sequence analysis showed the highest homology with the KADGH human isolate.Both SFTSVspecific recombinant N and Gn protein-based ELIS As revealed that 14.0%(30/215)and 7.9%(17/215)of collected blood specimens were positive for SFTSV antibody.These results demonstrate that the breeding farm deer are exposed to SFTSV and could be a potential infection source for humans through direct contact or consumption of byproducts.展开更多
Objective:To determine the current seroprevalence of antibodies against hepatitis A virus in selected group of children aged 1-6 years in Northern borders region,Saudi Arabia,and to identify risk factors for infection...Objective:To determine the current seroprevalence of antibodies against hepatitis A virus in selected group of children aged 1-6 years in Northern borders region,Saudi Arabia,and to identify risk factors for infection.Methods:A cross-sectional sero-epidemiological study of 950 children who attended 10 randomly selected primary health care centers(5 urban and 5 rural) was done.Parents of all children were subjected to a questionnaire including sociodemographic and housing environmental data.The determination of anti-HAV antibodies was carried out by ELISA-test.Results:The prevalence of HAV-IgG was 33.8%overall,35.5%among males and 32.0%among females with no statistically significant difference.Multivariate logistic regression analysis revealed that increasing age,rural residence,non Saudi nationality,and non availability of safe municipal water source were the most important independent predictors for HAV seropositivity in the studied children.Conclusions:There is a clear decrease in hepatitis A prevalence in the studied children particularly in urban areas and indicates that a transition may be underway to intermediate endemicity and possible shift of the risk to the adult age with increased morbidity.So,we recommend including Hepatitis A in the schedule of routine childhood vaccinations.展开更多
AIM:To investigate the current seroprevalence of hepatitis A virus(HAV) antibodies in patients with chronic viral liver disease in Korea.We also tried to identify the factors affecting the prevalence of HAV antibodies...AIM:To investigate the current seroprevalence of hepatitis A virus(HAV) antibodies in patients with chronic viral liver disease in Korea.We also tried to identify the factors affecting the prevalence of HAV antibodies. METHODS:We performed an analysis of the clinical records of 986 patients(mean age:49±9 years,714 males/272 females) with chronic hepatitis B virus(HBV) or hepatitis C virus(HCV) infection who had undergone HAV antibody testing between January 2008 and December 2009.RESULTS:The overall prevalence of IgG anti-HAV was 86.61%(854/986) in patients with chronic liver disease and was 88.13%(869/986) in age-and gendermatched patients from the Center for Health Promotion.The anti-HAV prevalence was 80.04%(405/506) in patients with chronic hepatitis B,86.96%(20/23) in patients with chronic hepatitis C,93.78%(422/450) in patients with HBV related liver cirrhosis,and 100%(7/7) in patients with HCV related liver cirrhosis.The anti-HAV prevalence according to the decade of age was as follows:20s(6.67%) ,30s(50.86%) ,40s(92.29%) ,50s(97.77%) ,and 60s(100%) .The antiHAV prevalence was significantly higher in patients older than 40 years compared with that in patients younger than 40 years of age.Multivariable analysis showed that age≥40 years,female gender and metropolitan cities as the place of residence were independent risk factors for IgG anti-HAV seropositivity. CONCLUSION:Most Korean patients with chronic liver disease and who are above 40 years of age have already been exposed to hepatitis A virus.展开更多
AIM:To determine the seroprevalence of anti-hepatitis A virus (HAV) antibodies in patients with chronic liver disease (CLD) and to justify the need for hepatitis A vaccination.METHODS:Patients (n=119) were enrolled be...AIM:To determine the seroprevalence of anti-hepatitis A virus (HAV) antibodies in patients with chronic liver disease (CLD) and to justify the need for hepatitis A vaccination.METHODS:Patients (n=119) were enrolled between July and September 2009.The diagnosis of CLD was based on the presence of viral markers for more than 6 mo.The diagnosis of liver cirrhosis was based on clinical,biochemical and radiological profiles.Patient serum was tested for anti-HAV IgG.RESULTS:The overall anti-HAV seroprevalence was 88.2%.The aetiology of CLD was hepatitis B in 96 patients (80.7%) and hepatitis C in 23 patients (19.3%).Mean age was 44.4 ± 14 years.Patients were grouped according to age as follows:24 (20.2%) patients in the 21-30 years age group,22 (18.5%) in the 31-40 years age group,31 (26.1%) in the 41-50 years age group,23(19.3%) in the 51-60 years age group and 19 (16.0%) patients aged greater than 60 years,with reported seroprevalences of 66.7%,95.5%,93.5%,91.3% and 94.7%,respectively.There was a marked increase of seroprevalence in subjects older than 30 years (P=0.001).CONCLUSION:Our study demonstrated that patients aged greater than 30 years of age were likely to have natural immunity to hepatitis A.Therefore,hepatitis A vaccination may not be routinely required in this age group.展开更多
ObjectiveTo determine the seroprevalence of anti-Toxoplasma gondii (T. gondii) IgG and IgM antibodies in HIV/AIDS patients and uninfected subjects.MethodsThis cross sectional survey was carried out on 78 healthy and 6...ObjectiveTo determine the seroprevalence of anti-Toxoplasma gondii (T. gondii) IgG and IgM antibodies in HIV/AIDS patients and uninfected subjects.MethodsThis cross sectional survey was carried out on 78 healthy and 62 HIV+/AIDS individuals in northern Iran between September 2007 and October 2008. Five mL of blood samples were collected from each person in case and control groups. Determination of CD4+ counts was performed by flow cytometry. The serum separated from blood samples was evaluated by conventional ELISA technique to determine the presence of antibodies to T. gondii.ResultsForty eight out of 62 (77.4%) HIV/AIDS serum samples were found positive for anti-T. gondii IgG antibody, compared with 59 among 78 (75.6%) HIV negative samples from the same area (P > 0.05). Six out of 62 (9.7%) HIV+/AIDS patients showed anti-T. gondii IgM antibody in their serum samples, compared with 7 among 78 (9%) HIV negative samples (P > 0.05). The mean of CD4+ counts in HIV+/AIDS was (430.8±182.3) cells/μL and in control group was (871.0±243.3)% cells/μL (P<0.01). CD4+ estimation in 5 (11.1%) of HIV+/AIDS patients was <200 cells/μL (P < 0.0001).ConclusionsSeroprevalence of latent toxoplasmosis in HIV patients is high, therefore the prevention of toxoplasmic encephalitis, administration of primary prophylaxis with co-trimoxazole to all HIV+/AIDS patients are necessary.展开更多
Maedi-visna virus（MVV） is an ovine lentivirus that is widespread in many countries worldwide.Both clinical and subclinical MVV infections cause substantial economic losses.MVV infection in live sheep is usually diag...Maedi-visna virus（MVV） is an ovine lentivirus that is widespread in many countries worldwide.Both clinical and subclinical MVV infections cause substantial economic losses.MVV infection in live sheep is usually diagnosed serologically,with antibody-positive sheep being regarded as infected.There have been few reports of maedi-visna in China,with no detailed epidemic analysis of MVV infection in ovine herds.In order to investigate the seroprevalence and spatial distribution of maedi-visna among ovine flocks in China,a total of 672 serum samples were collected from different ovine flocks in 12 regions（provinces,autonomous regions or municipalities） of China in 2011,and serum antibody levels were determined using a commercial ELISA Kit.This study represents the first investigation of the seroepidemiology of maedi-visna in China,indicating a circulation of MMV among sheep.展开更多
Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates...Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates of antiparvovirus b19 antibodies in a population of SCA patients and non-SCA healthy controls in Lagos, Nigeria. In this prospective cross-sectional study, we enrolled 73 confirmed SCA patients from 5 district hospitals in Lagos and 81 sex and age-matched non-SCA healthy controls. Serum sample from each study participant was screened for anti-parvovirus b19 by ELISA and PCR techniques. Standard biomedical assays were also done. Anti-parvovirus b19 IgM and IgG antibodies were detected in 22 （14.3%） and 97 （62.9%） of the 154 sera screened, 13 （17.8%） and 45 （61.6%） in SCA patients; 9 （11.1%） and 52 （64.2%） in non-SCA controls. The overall seronegativity rate was 19.5%. Parvovirus B19 DNA was found in 2 （11.1%） of the 18 IgM seropositive SCA serum samples screened. On the whole, parvovirus b19 infection was more commonly asymptomatic in non-SCA controls but caused significant elevation in liver enzymes in infected SCA patients （P 〈 0.05）. The risk of acute parvovirus b19 infection increased 65 times during unsteady state among the SCA patients. Although no deaths of infected patients were recorded during the study, age below 12 years, hospitalization and overcrowded environment were risk factors for infection. We conclude that parvovirus b19 is common in SCA patients, incurring greater susceptibility to infections.展开更多
Neospora caninum (N. caninum), an intracellular protozoan parasite, causes abortion and neonatal mortality in many herbivores including sheep and goats. The aim of this study was to estimate the Seroprevalence of N. c...Neospora caninum (N. caninum), an intracellular protozoan parasite, causes abortion and neonatal mortality in many herbivores including sheep and goats. The aim of this study was to estimate the Seroprevalence of N. caninum in sheep and goats in Grenada, West Indies. Sera were collected from 138 sheep and 138 goats from all six parishes of Grenada and Carriacou, a small island within Grenada. Animals were identified by gender. Sera were tested for antibodies for N. caninum using an indirect Enzyme Linked Immunosorbant Assay (ELISA) multispecies Kit from Pourquire Laboratorie (IDvet, France). Antibodies to N. caninum were detected in 18 of 138 sheep (13%, 95% confidence interval (CI): 7.39% to 18.61%) and 8 of 138 goats (5.8%, 95% CI: 1.9% to 9.7%). Although seropositivity was high in female sheep and in male goats, there was no statistical difference in seropositivity of males and females in both species of animals (p > 0.05, χ2). The results of this study revealed that sheep and goats in Grenada were exposed to N. caninum and dogs might be considered as a source of infection. There was a need to educate the farmers, possessing small ruminants, about the transmission cycle of N. caninum and methods of prevention, to minimize the exposure of their flocks. This is the first report on seroprevalence of N. caninum in Grenada, West Indies.展开更多
<strong>Introduction: </strong>Most febrile illnesses in Ghana are often misdiagnosed and presumptively treated as malaria. This situation may be due to the inappropriate diagnostic tool, clinical oversigh...<strong>Introduction: </strong>Most febrile illnesses in Ghana are often misdiagnosed and presumptively treated as malaria. This situation may be due to the inappropriate diagnostic tool, clinical oversight and lack of awareness of some of the disease conditions that might have been present in the country. This study sought to investigate the seroprevalence of dengue virus, geographical location of participants with circulating antibodies and finally evaluate the diagnostic accuracy of a Rapid diagnostic kit (RDT) using Enzyme Linked Immuno-Sorbent Assay (ELISA) as a gold standard for confirmation. <strong>Method: </strong>A hospital-based cross-sectional study was conducted among adults (≥18) attending the University of Cape Coast Hospital. From each participant, 3 - 4 ml of venous blood was drawn and serum was tested for IgG and IgM using RDT methods. Positive samples were selected for ELISA confirmation. Statistical analysis was performed using SPSS (v.20) and STATA (v.14) software. <strong>Results: </strong>A total of 270 participants were enrolled in the study. The geometric mean age was 32 years. Overall, Dengue virus (DENV) IgG seroprevalence by RDT was 10 (3.7%). Seroprevalence of IgG and IgM by the ELISA method was 34 (12.6%) and 6 (2.2%) respectively. Females recorded a high seroprevalence (7.4%) than males (5.2%) in terms of past exposure (IgG). On current exposure (IgM), females recorded a high seroprevalence (1.5%) than males (0.7%). Seroprevalence of individuals with dual positivity ((IgG + IgM+) (acute secondary infection) was 1.9%. Those with primary and recent infection (IgM+ only) were 0.4% whiles those with past and probably secondary infection (IgG+ only) were 10.7%. The odds of dengue exposure were significantly high among participants with ages 50 - 59 as compared to their other counterparts (AOR = 3.5, p = 0.03). Diagnostic accuracy of RDT kit was poor (Kappa value = 0.373 and 0.0001). Elmina was noted to record the highest seroprevalence values for both anti-dengue IgG (3.3%) and IgM (1.85%). <strong>Conclusion:</strong> The seroprevalence of anti-dengue IgG and IgM among participants suggests that dengue virus is in circulation in Cape Coast Metropolis and Komenda Edina Eguafo Abirem Municipality.展开更多
基金supported by the National Key Research and Development Program of China(2022YFE0114400).
文摘Toxoplasma gondii(T.gondii)is a globally distributed parasite that can infect a diversity of warm-blooded animals,including swine and humans.Infection in swine poses a considerable threat to food safety and public health.The aim of this meta-analysis was to estimate the seroprevalence of T.gondii infection in the swine population in China from 2000 to 2023 and to examine potential factors associated with infection.A total of 112 studies were included,collectively involving 145,152 swine samples originating from 26 provinces.The pooled seroprevalence was 26.0%(95%CI:23.3%–28.7%).Stratified analysis based on diagnostic methods revealed that studies using the indirect hemagglutination assay(IHA)reported a seroprevalence of 19.7%(95%CI:17.2%–22.2%),whereas those utilizing the enzyme-linked immunosorbent assay(ELISA)reported a higher seroprevalence of 35.5%(95%CI:29.1%–41.8%).Geographical analysis indicated higher seroprevalence in the South Central and Southwest regions,whereas the East and Northwest areas reported the lowest seroprevalence.Chongqing Province reported the highest seroprevalence,reaching 44.9%(95%CI:43.4%–46.0%),followed by Xinjiang,Hainan,and Guizhou,whereas the lowest was observed in Shandong Province(3.5%,95%CI:1.7%–6.1%).These findings provide important epidemiological evidence that can inform strategies for the prevention and control of T.gondii infection in swine populations,with a focus on high-risk populations and geographical areas.This imperative contributes substantially to the improvement of both food safety and public health.
基金supported by the National Key Research and Development Programme of China[Grant Number 2021YFC2300900,2022YFC2302700]International Partnership Programme of the Bureau of International Cooperation,Chinese Academy of Sciences[Grant Number 153B42KYSB20200013]+1 种基金National Natural Science Foundation of China[Grant Number U22A20363]Biological Resources Programme,Chinese Academy of Sciences[Grant Number KFJ-BRP-017-74].
文摘Infectious diseases caused by arboviruses are a public health concern in Pakistan.However,studies on data prevalence and threats posed by arboviruses are limited.This study investigated the seroprevalence of arboviruses in a healthy population in Pakistan,including severe fever with thrombocytopenia syndrome virus(SFTSV),Crimean-Congo hemorrhagic fever virus(CCHFV),Tamdy virus(TAMV),and Karshi virus(KSIV)based on a newly established luciferase immunoprecipitation system(LIPS)assays,and Zika virus(ZIKV)by enzyme-linked immunosorbent assays(ELISA).Neutralizing activities against these arboviruses were further examined from the antibody positive samples.The results showed that the seroprevalence of SFTSV,CCHFV,TAMV,KSIV,and ZIKV was 17.37%,7.58%,4.41%,1.10%,and 6.48%,respectively,and neutralizing to SFTSV(1.79%),CCHFV(2.62%),and ZIKV(0.69%)were identified,as well as to the SFTSV-related Guertu virus(GTV,0.83%).Risk factors associated with the incidence of exposure and levels of antibody response were analyzed.Moreover,co-exposure to different arboviruses was demonstrated,as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing activity.Males,individuals aged40 years,and outdoor workers had a high risk of exposure to arboviruses.All these results reveal the substantial risks of infection with arboviruses in Pakistan,and indicate the threat from co-exposure to multiple arboviruses.The findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.
文摘In Zanzibar, from the start of the pandemic in March 2020 to the time of sampling in December 2020, SARS-CoV-2 seroprevalence data was limited. We conducted a seroprevalence study to evaluate the magnitude of SARS-CoV-2 exposure among healthcare workers, school children, and people who attended general markets in Zanzibar. The objectives of the study were to analyse the total antibodies from selected higher-risk population groups in order to determine magnitude in SARS CoV-2 exposure. Blood samples were collected from eligible and consented participants (adults and children), and their serum was analyzed for total antibodies against SARS-CoV-2 using ELISA. A questionnaire was used to collect participants’ demographic and clinical data. The overall SARS-CoV-2 seroprevalence across all age groups was 33%, and a higher seroprevalence was observed in the 40 - 49 years’ age group relative to other ages as well as in those who attended markets. A runny nose (18.8% of participants) was the most frequently reported SARS-CoV-2 infection-related symptom. Multivariable analysis showed significantly higher odds of infection in people living in urban districts. The findings provide insight into SARS-CoV-2 infection among school children, health workers, and people who attended markets in Zanzibar in the early stages of the pandemic. Exposure in these groups might have been influenced by infection and prevention strategies taken by the government, as well as shopping behavior, school overcrowding, and population density in urban settings. The study had methodological limitations, including cross-sectional design. Further, well-designed, longitudinal studies are recommended to understand exposure and transmission at a population level.
文摘Blood transfusion saves lives and reduces morbidity and mortality for a large number of diseases and clinical conditions, but it is not without danger. The aim of this study was to determine the seroprevalence of HIV and hepatitis B in blood donors received at the regional Blood Transfusion Centre of N’Zérékoré (Guinea). This was a 5-year retrospective analytical study. We included records of blood donors aged 18 to 60 years admitted to the N’Zérékoré Regional Blood Transfusion Centre for blood donation from January 2016 to December 2020. We performed a descriptive analysis followed by Chi-2 or Fish-er-exact tests and the Student or Wilcoxon test, followed by multivariate logistic regression. In this study, donor age ranged from 18 - 60 years, with a pre-dominance of donors aged 25 - 34 (44.2%). Male donors were the most represented in our study (79.0% versus 21.0% female). More than half of the donors were blood group O (55.6%). We observed a seroprevalence of 3.6% for HIV, 13.4% for HBsAg and 0.2% for co-infection. In our series, age 25 - 34 (OR = 1.89 and P = 0.001) and 35 - 44 for HIV (OR = 2.01 and P = 0.001), HBsAgserostatus (OR = 3.04 and P = 0.001) and blood donation history (OR of 3.04 and P = 0.001) were factors associated with HIV positivity (P < 0.05). In our study, HIV serostatus (OR = 3.04 and P = 0.001) and blood donation history (OR = 0.01 and P = 0.001) were factors associated with HBsAgseropositivity. We reported a high prevalence of HIV and HBsAg. Sex, serological status and blood donation history were associated factors.
基金supported by the National Key Research and Development Program of China (2018YFC1200100)the Guangzhou Science and Technology Program Key Project, China (201803040004)+2 种基金the National Science and Technology Major Project of China (2017ZX10103011003, 2018ZX10102001)the National Natural Science Foundation of China, China (31570163)the Youth Project of State Key Laboratory of Respiratory Disease, China (SKLRD-QN-201713)。
文摘Human adenoviruses(HAdVs) commonly cause many diseases such as respiratory diseases, gastroenteritis, cystitis worldwide. HAdV-3,-7,-4 and emergent HAdV-55 and HAdV-14 are the most important types causing severe respiratory diseases. There is no effective drug available for clinical treatment, and no vaccine available for the general population.Therefore, it is important to investigate the seroprevalence against HAdV for developing novel vaccines and vectors. In this study, we investigated the seroprevalence and titer levels of neutralizing antibodies(NAb) against HAdV-3,-4,-7,-14,-55,and-11 in total 278 healthy populations between 0 months and 49 years of age(228 children and 50 adults) from Guangzhou. In children under the age of 18 years, the seropositive rates were significantly increased against HAdV-3 at12.07%, 33.96%, and 64.29% and against HAdV-7 at 0%, 18.87%, and 19.05% in age groups of 1–2, 3–5, and 6–17 years,respectively. The seroprevalence was very low(0% - 8.1%) for all other four types. In adults aged between 18 and49 years, HAdV-3,-4, and-7(> 50.00%) were the most common types, followed by HAdV-14(38.00%),-55(34.00%),and-11(24.00%). Adults tended to have high NAb titers against HAdV-4 and-55. HAdV-55-seropositive donors tended to be HAdV-11-and HAdV-14-seropositive. These results indicated the low level of herd immunity against all six HAdV types in young children, and HAdV-14,-55,-11 in adults from Guangzhou City. Our findings demonstrate the importance of monitoring HAdV types and developing vaccines against HAdV for children and adults.
基金supported by the National Science and Technology Major Projects[No.2018ZX10712001 and2017ZX10303404]Major Infectious Diseases Such as AIDS and Viral Hepatitis Prevention and Control Technology Major Projects[No.2018ZX10712-001].
文摘Serum samples were tested for Bartonella henselae Ig G antibodies using indirect immunofluorescence assays.We then analyzed associated risk factors.Serum samples were considered positive when reactive at a dilution of more than 1:320.
基金supported by grants from the National Natural Science Foundation of China (81471957, 81772172, 81671971, U1602223 and 81871641)a grant from the Open Research Projects of Key Laboratory of Beijing Ditan Hospital, Capital Medical University (DTKF201705)
文摘The incidence of Japanese encephalitis(JE)has significantly decreased in China due to JE vaccines.In this study,we investigated the post-JE vaccination seroprevalence and protection provided by vaccinated sera against Japanese encephalitis virus(JEV)to elucidate the persistence and waning of antibodies to JEV among JE-SA14-14-2-vaccinated children.A total of 300 serum samples were collected from vaccinated children aged 3-10 years in Zhaotong,Yunnan,China.The seroprevalence of anti-JEV antibodies was determined by enzyme-linked immune sorbent assay and plaque reduction neutralization test.The highest seropositivity of 82%was observed in vaccinated children during the first 0.5-1.5 years after booster vaccination.Then,the seropositivity began to decline and remained lower than the original level observed in the 0.5-1.5-year group.An association was found between the waning of seroprevalence and elapsed time of the post-booster vaccination.Similarly,the neutralizing antibody(nAb)titres gradually decreased over time,and the levels showed a positive correlation with the protective efficacy in mice.This finding suggests that nAbs play an important role in the antiviral process and that the nAb titre is an adequately credible parameter for evaluating the protective efficacy induced by the JE vaccine.Our results provide data that clarify the persistence and waning of antibodies to JEV,which may help elucidate the pathogenesis of JE.
基金Supported by the VLIR UOS Project(Grant N.VLIR:42/FA02000/13/5806),University of Antwerp and University of Kinshasa
文摘Objective:To determine the seroprevalence of toxoplasmosis in pregnant women,as well as the proportion of acutely infected and risk factors in the Democratic Republic of Congo.Methods:Thirty maternities in Kinshasa were randomly selected and women attending antenatal consultation were invited to participate.They were interviewed with a structured questionnaire about known risk factors(age,meat consumption,contact with soil,and presence of cat)and a venous blood sample was taken.Sera were analysed for total immunoglobulins(Ig)by VIDAS Toxo Competition using Enzyme Linked Fluorescent Assay.IgM was determined by VIDIA Toxo IgM and IgG avidity by VIDAS Toxo IgG avidity.Results:A total of 781 women were included.Median age was 28 years old(IQR:8.S).And 627women(80.3%;95%CI:77.5-83.1)were found to be positive to total Ig and 17 out of 387(4.4%;95%CI:2.3-6.4)were positive to IgM.IgC avidity was low for 2(11.8%)women,intermediate for 2(11.8%)and high for 13 women(76.4%).There was no statistically significant association between Toxoplasma gondii infection and any risk factors assessed.Conclusion:In Kinshasa,toxoplasmosis endemicity is highly prevalent.One woman out of twenty five had a recent toxoplasmosis infection and 20%were not protected against primoinfection,indicating a need for measures to prevent and control toxoplasmosis during pregnancy.
文摘Objective:To report our experience with two tests,anti-cardiolipin antibody test[venereal disease reasearch laboratory(VDRL) test]and specific treponemal test(Treponema pallidum hemagglutination assay),used for screening antenatal,high risk cases and cases from sexually transmitted infection in a tertiary care hospital from January 2006 till December 2008.Methods:A total of 14639 samples received from various patient groups including antenatal cases,patients attending sexually transmitted disease(STD) clinic,blood donors and HIV positive patients were screened.Results:Among the 14639 samples collected,103 were positive by VDRL test.Of these 89 cases were confirmed by quantitative VDRL test and Treponema pallidum hemagglutination assay.The cumulative seroprevalence over two years was found to be 0.61%in this study.The syphilis seroprevalence reduced from 0.88%in 2006 to 0.40%in 2008.Among the various sub-populations studied,patients attending the sexually transmitted infection clinic showed a seroprevalence of 2.62%.The seroprevalence decreased significantly from 4.00%in 2006 to1.39%in 2008.Conclusions:Our study showed a statistically significant declining rate of syphilis in STD clinics as well as the overall seroprevalence.These findings could be interpreted as indicators of improved programmes for prevention and management of STDs.
基金Supported by University Research Publication Committee(URPC),Fiji National University,No.ACT339Hepatitis B Free(HBF)Ltd,Australia,No.25 167 817 389
文摘AIMTo determine the seroprevalence of hepatitis B surface antigen (HBsAg) among pregnant women attending antenatal clinic in Honiara, Solomon Islands. METHODSThis descriptive cross-sectional study was carried out in seven area health centers in Honiara. From March to June 2015, identification of eligible pregnant women in each site was conducted using systematic random sampling technique. A total of 243 pregnant women who gave written informed consent were enrolled. Standardized tool was used to record demographics, obstetric history and serology results. HBsAg and hepatitis B e antigen (HBeAg) were tested using point-of-care rapid diagnostic test. All HBsAg positive samples were verified using enzyme-linked immunosorbent assay. RESULTSThe mean age of participants was 26 ± 6 years. The overall hepatitis HBsAg prevalence was 13.8% with higher rate (22%) reported in women between 30-34 years of age. Majority of HBsAg positive participants were Melanesians (29 out for 33). None of the pregnant women in the 15-19 years and ≥ 40 years tested positive for HBsAg. There was no statistically significant difference in HBsAg prevalence by age, ethnicity, education and residential location. The overall HBeAg seroprevalence was 36.7%. Women between 20-24 years of age had the highest rate of 54.5%. Low level of knowledge about hepatitis B vaccination was reputed. Overall, 54.6% of participants were not aware of their hepatitis B vaccination status and only 65.2% of mothers reported their child had been vaccinated. CONCLUSIONHepatitis B is a disease of public health importance in Solomon Islands and emphasize the need for integrated preventative interventions for its control.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB29050701)the Emergency Key Program of Guangzhou (EKPG21-20)+2 种基金the China Evergrande Group funding for SARS-Co V-2 (2020GIRHHMS22)the Zhongnanshan Medical Foundation of Guangdong Province (ZNSA-2022009)the China Postdoctoral Science Foundation (2020M682942)
文摘Human adenoviruses type 26(HAdV26)and type 35(HAdV35)have increasingly become the choice of adenovirus vectors for vaccine application.However,the population pre-existing immunity to these two adenoviruses in China,which may reduce vaccine efficacy,remains largely unknown.Here,we established micro-neutralizing(MN)assays to investigate the seroprevalence of neutralizing antibodies(nAbs)against HAdV26 and HAdV35 in the general population of Guangdong and Shandong provinces,China.A total of 1184 serum samples were collected,47.0%and 15.8%of which showed HAdV26 and HAdV35 nAb activity,respectively.HAdV26-seropositive individuals tended to have more moderate nAbs titers(201-1000),while HAdV35-seropositive individuals appeared to have more low nAbs titers(72-200).The seropositive rates of HAdV26 and HAdV35 in individuals younger than 20 years old were very low.The seropositive rates of HAdV26 increased with age before 70 years old and decreased thereafter,while HAdV35 seropositive rates did not show similar characteristics.Notably,the seropositive rates and nAb levels of both HAdV26 and HAdV35 were higher in Guangdong Province than in Shandong Province,but did not exert significant differences between males and females.The seroprevalence between HAdV26 and HAdV35 showed little correlation,and no significant cross-neutralizing activity was detected.These results clarified the characteristics of the herd immunity against HAdV26 and HAdV35,and provided information for the rational development and application of HAdV26 and HAdV35 as vaccine vectors in China.
基金supported by the Ministry of Health & Welfare (government—wide R&D fund project for infectious disease research (HG18C0029)
文摘Severe fever with thrombocytopenia syndrome phlebovirus(SFTSV)has a wide host range.Not only has it been found in humans,but also in many wild and domesticated animals.The infection of breeding deer on farms is a particularly worrisome public health concern due to the large amount of human contact and the diverse use of deer products,including raw blood.To investigate the prevalence of breeding domesticated deer,we examined the SFTSV infection rate on deer farms in South Korea from 2015 to 2017.Of the 215 collected blood samples,0.9%(2/215)were found to be positive for viral RNA by PCR,and sequence analysis showed the highest homology with the KADGH human isolate.Both SFTSVspecific recombinant N and Gn protein-based ELIS As revealed that 14.0%(30/215)and 7.9%(17/215)of collected blood specimens were positive for SFTSV antibody.These results demonstrate that the breeding farm deer are exposed to SFTSV and could be a potential infection source for humans through direct contact or consumption of byproducts.
文摘Objective:To determine the current seroprevalence of antibodies against hepatitis A virus in selected group of children aged 1-6 years in Northern borders region,Saudi Arabia,and to identify risk factors for infection.Methods:A cross-sectional sero-epidemiological study of 950 children who attended 10 randomly selected primary health care centers(5 urban and 5 rural) was done.Parents of all children were subjected to a questionnaire including sociodemographic and housing environmental data.The determination of anti-HAV antibodies was carried out by ELISA-test.Results:The prevalence of HAV-IgG was 33.8%overall,35.5%among males and 32.0%among females with no statistically significant difference.Multivariate logistic regression analysis revealed that increasing age,rural residence,non Saudi nationality,and non availability of safe municipal water source were the most important independent predictors for HAV seropositivity in the studied children.Conclusions:There is a clear decrease in hepatitis A prevalence in the studied children particularly in urban areas and indicates that a transition may be underway to intermediate endemicity and possible shift of the risk to the adult age with increased morbidity.So,we recommend including Hepatitis A in the schedule of routine childhood vaccinations.
文摘AIM:To investigate the current seroprevalence of hepatitis A virus(HAV) antibodies in patients with chronic viral liver disease in Korea.We also tried to identify the factors affecting the prevalence of HAV antibodies. METHODS:We performed an analysis of the clinical records of 986 patients(mean age:49±9 years,714 males/272 females) with chronic hepatitis B virus(HBV) or hepatitis C virus(HCV) infection who had undergone HAV antibody testing between January 2008 and December 2009.RESULTS:The overall prevalence of IgG anti-HAV was 86.61%(854/986) in patients with chronic liver disease and was 88.13%(869/986) in age-and gendermatched patients from the Center for Health Promotion.The anti-HAV prevalence was 80.04%(405/506) in patients with chronic hepatitis B,86.96%(20/23) in patients with chronic hepatitis C,93.78%(422/450) in patients with HBV related liver cirrhosis,and 100%(7/7) in patients with HCV related liver cirrhosis.The anti-HAV prevalence according to the decade of age was as follows:20s(6.67%) ,30s(50.86%) ,40s(92.29%) ,50s(97.77%) ,and 60s(100%) .The antiHAV prevalence was significantly higher in patients older than 40 years compared with that in patients younger than 40 years of age.Multivariable analysis showed that age≥40 years,female gender and metropolitan cities as the place of residence were independent risk factors for IgG anti-HAV seropositivity. CONCLUSION:Most Korean patients with chronic liver disease and who are above 40 years of age have already been exposed to hepatitis A virus.
基金Supported by Short term grant No. 304/PPSP/61310014 from the Universiti Sains Malaysia
文摘AIM:To determine the seroprevalence of anti-hepatitis A virus (HAV) antibodies in patients with chronic liver disease (CLD) and to justify the need for hepatitis A vaccination.METHODS:Patients (n=119) were enrolled between July and September 2009.The diagnosis of CLD was based on the presence of viral markers for more than 6 mo.The diagnosis of liver cirrhosis was based on clinical,biochemical and radiological profiles.Patient serum was tested for anti-HAV IgG.RESULTS:The overall anti-HAV seroprevalence was 88.2%.The aetiology of CLD was hepatitis B in 96 patients (80.7%) and hepatitis C in 23 patients (19.3%).Mean age was 44.4 ± 14 years.Patients were grouped according to age as follows:24 (20.2%) patients in the 21-30 years age group,22 (18.5%) in the 31-40 years age group,31 (26.1%) in the 41-50 years age group,23(19.3%) in the 51-60 years age group and 19 (16.0%) patients aged greater than 60 years,with reported seroprevalences of 66.7%,95.5%,93.5%,91.3% and 94.7%,respectively.There was a marked increase of seroprevalence in subjects older than 30 years (P=0.001).CONCLUSION:Our study demonstrated that patients aged greater than 30 years of age were likely to have natural immunity to hepatitis A.Therefore,hepatitis A vaccination may not be routinely required in this age group.
基金supported by funds from Mazandaran University of Medical sciences(No.86-115),Iran
文摘ObjectiveTo determine the seroprevalence of anti-Toxoplasma gondii (T. gondii) IgG and IgM antibodies in HIV/AIDS patients and uninfected subjects.MethodsThis cross sectional survey was carried out on 78 healthy and 62 HIV+/AIDS individuals in northern Iran between September 2007 and October 2008. Five mL of blood samples were collected from each person in case and control groups. Determination of CD4+ counts was performed by flow cytometry. The serum separated from blood samples was evaluated by conventional ELISA technique to determine the presence of antibodies to T. gondii.ResultsForty eight out of 62 (77.4%) HIV/AIDS serum samples were found positive for anti-T. gondii IgG antibody, compared with 59 among 78 (75.6%) HIV negative samples from the same area (P > 0.05). Six out of 62 (9.7%) HIV+/AIDS patients showed anti-T. gondii IgM antibody in their serum samples, compared with 7 among 78 (9%) HIV negative samples (P > 0.05). The mean of CD4+ counts in HIV+/AIDS was (430.8±182.3) cells/μL and in control group was (871.0±243.3)% cells/μL (P<0.01). CD4+ estimation in 5 (11.1%) of HIV+/AIDS patients was <200 cells/μL (P < 0.0001).ConclusionsSeroprevalence of latent toxoplasmosis in HIV patients is high, therefore the prevention of toxoplasmic encephalitis, administration of primary prophylaxis with co-trimoxazole to all HIV+/AIDS patients are necessary.
基金supported by the fund of China Agriculture Research System(CARS-39)
文摘Maedi-visna virus（MVV） is an ovine lentivirus that is widespread in many countries worldwide.Both clinical and subclinical MVV infections cause substantial economic losses.MVV infection in live sheep is usually diagnosed serologically,with antibody-positive sheep being regarded as infected.There have been few reports of maedi-visna in China,with no detailed epidemic analysis of MVV infection in ovine herds.In order to investigate the seroprevalence and spatial distribution of maedi-visna among ovine flocks in China,a total of 672 serum samples were collected from different ovine flocks in 12 regions（provinces,autonomous regions or municipalities） of China in 2011,and serum antibody levels were determined using a commercial ELISA Kit.This study represents the first investigation of the seroepidemiology of maedi-visna in China,indicating a circulation of MMV among sheep.
文摘Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates of antiparvovirus b19 antibodies in a population of SCA patients and non-SCA healthy controls in Lagos, Nigeria. In this prospective cross-sectional study, we enrolled 73 confirmed SCA patients from 5 district hospitals in Lagos and 81 sex and age-matched non-SCA healthy controls. Serum sample from each study participant was screened for anti-parvovirus b19 by ELISA and PCR techniques. Standard biomedical assays were also done. Anti-parvovirus b19 IgM and IgG antibodies were detected in 22 （14.3%） and 97 （62.9%） of the 154 sera screened, 13 （17.8%） and 45 （61.6%） in SCA patients; 9 （11.1%） and 52 （64.2%） in non-SCA controls. The overall seronegativity rate was 19.5%. Parvovirus B19 DNA was found in 2 （11.1%） of the 18 IgM seropositive SCA serum samples screened. On the whole, parvovirus b19 infection was more commonly asymptomatic in non-SCA controls but caused significant elevation in liver enzymes in infected SCA patients （P 〈 0.05）. The risk of acute parvovirus b19 infection increased 65 times during unsteady state among the SCA patients. Although no deaths of infected patients were recorded during the study, age below 12 years, hospitalization and overcrowded environment were risk factors for infection. We conclude that parvovirus b19 is common in SCA patients, incurring greater susceptibility to infections.
文摘Neospora caninum (N. caninum), an intracellular protozoan parasite, causes abortion and neonatal mortality in many herbivores including sheep and goats. The aim of this study was to estimate the Seroprevalence of N. caninum in sheep and goats in Grenada, West Indies. Sera were collected from 138 sheep and 138 goats from all six parishes of Grenada and Carriacou, a small island within Grenada. Animals were identified by gender. Sera were tested for antibodies for N. caninum using an indirect Enzyme Linked Immunosorbant Assay (ELISA) multispecies Kit from Pourquire Laboratorie (IDvet, France). Antibodies to N. caninum were detected in 18 of 138 sheep (13%, 95% confidence interval (CI): 7.39% to 18.61%) and 8 of 138 goats (5.8%, 95% CI: 1.9% to 9.7%). Although seropositivity was high in female sheep and in male goats, there was no statistical difference in seropositivity of males and females in both species of animals (p > 0.05, χ2). The results of this study revealed that sheep and goats in Grenada were exposed to N. caninum and dogs might be considered as a source of infection. There was a need to educate the farmers, possessing small ruminants, about the transmission cycle of N. caninum and methods of prevention, to minimize the exposure of their flocks. This is the first report on seroprevalence of N. caninum in Grenada, West Indies.
文摘<strong>Introduction: </strong>Most febrile illnesses in Ghana are often misdiagnosed and presumptively treated as malaria. This situation may be due to the inappropriate diagnostic tool, clinical oversight and lack of awareness of some of the disease conditions that might have been present in the country. This study sought to investigate the seroprevalence of dengue virus, geographical location of participants with circulating antibodies and finally evaluate the diagnostic accuracy of a Rapid diagnostic kit (RDT) using Enzyme Linked Immuno-Sorbent Assay (ELISA) as a gold standard for confirmation. <strong>Method: </strong>A hospital-based cross-sectional study was conducted among adults (≥18) attending the University of Cape Coast Hospital. From each participant, 3 - 4 ml of venous blood was drawn and serum was tested for IgG and IgM using RDT methods. Positive samples were selected for ELISA confirmation. Statistical analysis was performed using SPSS (v.20) and STATA (v.14) software. <strong>Results: </strong>A total of 270 participants were enrolled in the study. The geometric mean age was 32 years. Overall, Dengue virus (DENV) IgG seroprevalence by RDT was 10 (3.7%). Seroprevalence of IgG and IgM by the ELISA method was 34 (12.6%) and 6 (2.2%) respectively. Females recorded a high seroprevalence (7.4%) than males (5.2%) in terms of past exposure (IgG). On current exposure (IgM), females recorded a high seroprevalence (1.5%) than males (0.7%). Seroprevalence of individuals with dual positivity ((IgG + IgM+) (acute secondary infection) was 1.9%. Those with primary and recent infection (IgM+ only) were 0.4% whiles those with past and probably secondary infection (IgG+ only) were 10.7%. The odds of dengue exposure were significantly high among participants with ages 50 - 59 as compared to their other counterparts (AOR = 3.5, p = 0.03). Diagnostic accuracy of RDT kit was poor (Kappa value = 0.373 and 0.0001). Elmina was noted to record the highest seroprevalence values for both anti-dengue IgG (3.3%) and IgM (1.85%). <strong>Conclusion:</strong> The seroprevalence of anti-dengue IgG and IgM among participants suggests that dengue virus is in circulation in Cape Coast Metropolis and Komenda Edina Eguafo Abirem Municipality.
