Influenza,an acute respiratory infectious disease caused by the influenza virus,exhibits distinct seasonal patterns in China,with peak activity occurring in winter and spring in northern regions,and in winter and summ...Influenza,an acute respiratory infectious disease caused by the influenza virus,exhibits distinct seasonal patterns in China,with peak activity occurring in winter and spring in northern regions,and in winter and summer in southern areas[1].The World Health Organization(WHO)emphasizes that early warning and epidemic intensity assessments are critical public health strategies for influenza prevention and control.Internet-based flu surveillance,with real-time data and low costs,effectively complements traditional methods.The Baidu Search Index,which reflects flu-related queries,strongly correlates with influenza trends,aiding in regional activity assessment and outbreak tracking[2].展开更多
A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t...A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.展开更多
The numerical approximation of stochastic partial differential equations(SPDEs),particularly those including q-diffusion,poses considerable challenges due to the requirements for high-order precision,stability amongst...The numerical approximation of stochastic partial differential equations(SPDEs),particularly those including q-diffusion,poses considerable challenges due to the requirements for high-order precision,stability amongst random perturbations,and processing efficiency.Because of their simplicity,conventional numerical techniques like the Euler-Maruyama method are frequently employed to solve stochastic differential equations;nonetheless,they may have low-order accuracy and lower stability in stiff or high-resolution situations.This study proposes a novel computational scheme for solving SPDEs arising from a stochastic SEIR model with q-diffusion and a general incidence rate function.A proposed computational scheme can be used to solve stochastic partial differential equations.For spatial discretization,a compact scheme is chosen.The compact scheme can provide a sixth-order accurate solution.The proposed scheme can be considered an extension of the Euler Maruyama method.Stability and consistency in the mean square sense are also provided.For application purposes,the stochastic SEIR model is considered using q-diffusion effects.The scheme is used to solve the stochastic model and compared with the Euler-Maruyama method.The scheme is also compared with nonstandard finite difference method for solving deterministic models.In both cases,it performs better than existing schemes.Incorporating q-diffusion further enhanced the model’s ability to represent realistic spatial-temporal disease dynamics,especially in scenarios where classical diffusion is insufficient.展开更多
Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt pro...Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt protective measures.However, whether to disseminate specific information is also a behavioral decision. In light of this understanding, we develop a coupled information–vaccination–epidemic model to depict these co-evolutionary dynamics in a three-layer network. Negative information dissemination and vaccination are treated as separate decision-making processes. We then examine the combined effects of herd and risk motives on information dissemination and vaccination decisions through the lens of game theory. The microscopic Markov chain approach(MMCA) is used to describe the dynamic process and to derive the epidemic threshold. Simulation results indicate that increasing the cost of negative information dissemination and providing timely clarification can effectively control the epidemic. Furthermore, a phenomenon of diminishing marginal utility is observed as the cost of dissemination increases, suggesting that authorities do not need to overinvest in suppressing negative information. Conversely, reducing the cost of vaccination and increasing vaccine efficacy emerge as more effective strategies for outbreak control. In addition, we find that the scale of the epidemic is greater when the herd motive dominates behavioral decision-making. In conclusion, this study provides a new perspective for understanding the complexity of epidemic spreading by starting with the construction of different behavioral decisions.展开更多
The host intestinal microbiota has emerged as the third element in the interactions between hosts and enteric viruses,and potentially affects the infection processes of enteric viruses.However,the interaction of porci...The host intestinal microbiota has emerged as the third element in the interactions between hosts and enteric viruses,and potentially affects the infection processes of enteric viruses.However,the interaction of porcine enteric coronavirus with intestinal microorganisms during infection remains unclear.In this study,we used 16S-rRNA-based Illumina NovaSeq high-throughput sequencing to identify the changes in the intestinal microbiota of piglets mediated by porcine epidemic diarrhea virus(PEDV)infection and the effects of the alterations in intestinal bacteria on PEDV infection and its molecular mechanisms.The intestinal microbiota of PEDV-infected piglets had significantly less diversity than the healthy group and different bacterial community characteristics.Among the altered intestinal bacteria,the relative abundance of Clostridium perfringens was significantly increased in the PEDV-infected group.A strain of C.perfringens type A,named DQ21,was successfully isolated from the intestines of healthy piglets.The metabolites of swine C.perfringens type A strain DQ21 significantly enhanced PEDV replication in porcine intestinal epithelial cell clone J2(IPEC-J2)cells,and PEDV infection and pathogenicity in suckling piglets.Palmitic acid(PA)was identified as one of those metabolites with metabolomic technology,and significantly enhanced PEDV replication in IPEC-J2 cells and PEDV infection and pathogenicity in suckling piglets.PA also increased the neutralizing antibody titer in the immune sera of mice.Furthermore,PA mediated the palmitoylation of the PEDV S protein,which improved virion stability and membrane fusion,thereby enhancing viral infection.Overall,our study demonstrates a novel mechanism of PEDV infection,with implications for PEDV pathogenicity.展开更多
Porcine epidemic diarrhea(PED),caused by porcine epidemic diarrhea virus(PEDV),can induce 80–100%mortality in newborn piglets;therefore,specific and rapid detection methods are important for the prevention of this vi...Porcine epidemic diarrhea(PED),caused by porcine epidemic diarrhea virus(PEDV),can induce 80–100%mortality in newborn piglets;therefore,specific and rapid detection methods are important for the prevention of this viral infection.In particular,methods for detecting neutralizing antibodies(nAbs)can be used to evaluate the immunization effect of PEDV vaccines.The spike protein of PEDV(PEDV-S)has been universally used as an antigen to develop immunoassays to detect nAbs.Nanobodies(Nbs)offer advantages such as ease of genetic engineering and low production costs,making them promising for diagnostic applications.In this study,PEDV-S was expressed via the baculovirus system and was used as an antigen to immunize Bactrian camels.A total of 10 Nbs against PEDV-S were first screened and expressed as fusion proteins with horseradish peroxidase(HRP)in HEK293T cells.A Nb-HRP fusion protein named PEDV-S-Nb13-HRP was subsequently selected and used as a probe for developing a competitive enzyme-linked immunosorbent assay(cELISA)to detect anti-PEDV nAbs.Optimization assays identified 80 ng/well of PEDV-S as the optimal coating antigen concentration.The optimal dilution of PEDV-S-Nb13-HRP was 1:200,and the optimal serum dilution was 1:10.The cutoff value of cELISA was determined as 28.1%,demonstrating high specificity,repeatability,stability,and good agreement rates with two commercial ELISA kits(93.6%)and a serum neutralization test(96.34%).Additionally,the results of the detection of IgA antibodies in oral and milk samples from sows were in good agreement with those of the IDEXX PEDV IgA kit.These results demonstrate that the cELISA is a reliable and cost-effective method for detecting anti-PEDV nAbs.展开更多
The cross-species infection of coronaviruses has resulted in several major epidemics since 2003.Porcine epidemic diarrhea virus(PEDV)is a devastating swine enteric coronavirus,which targets pigs as the only natural re...The cross-species infection of coronaviruses has resulted in several major epidemics since 2003.Porcine epidemic diarrhea virus(PEDV)is a devastating swine enteric coronavirus,which targets pigs as the only natural reservoir.In this study,the nucleic acid of PEDV was detected in rat fecal samples collected from pig farms.Further animal tests showed that PEDV can cause systemic infections in neonatal mice and rats via intracranial inoculation.The brain,lung,intestine and spleen were all targets for PEDV in rodents in contrast to the intestine being targeted in pigs.Morbidity and mortality vary via different infection routes.PEDV was also detectable in feces after infection,suggesting that the infected rodents were potential infectious sources.Moreover,the cerebral tropism of PEDV was verified in piglets via orally inoculation,which had not been identified before.In conclusion,our findings demonstrate that PEDV could cross the species barrier to infect mice and rats through different routes in experimental settings.Although it is highly devastating to piglets,PEDV changes the target organs and turns to be milder when meeting with new hosts.Based on these findings,more attention should be paid to the potential cross-species infection of PEDV.展开更多
Porcine epidemic diarrhea virus(PEDV)infection causes acute watery diarrhea in neonatal piglets,leading to substantial economic losses within the pig farming industry.This study demonstrates that clofazimine(CFZ)signi...Porcine epidemic diarrhea virus(PEDV)infection causes acute watery diarrhea in neonatal piglets,leading to substantial economic losses within the pig farming industry.This study demonstrates that clofazimine(CFZ)significantly inhibits PEDV replication in a dose-dependent manner in vitro,with negligible cytotoxicity.Findings from our time-of-addition assays indicate that CFZ effectively disrupts multiple stages of the viral infection cycle.Using a CoV-RdRp-Gluc reporter system,we evaluated the potency of CFZ against PEDV RNA-dependent RNA polymerase(RdRp),and determined a low IC50 value of 0.1364μM.Molecular docking studies further confirmed that CFZ has high binding affinity at the active sites of the spike protein and RdRp protein in PEDV.Transcriptome analysis of Vero E6 cells,with and without CFZ treatment,revealed a significant change in transcriptional activity at 8 h postinfection(hpi).Moreover,the simultaneous application of CFZ and nucleoside analogs showed enhanced the anti-PEDV effect of CFZ in vitro.Our study underscores the potential of CFZ as a viable therapeutic agent against PEDV.展开更多
In this paper,based on the SVIQR model we develop a stochastic epidemic model with multiple vaccinations and time delay.Firstly,we prove the existence and uniqueness of the global positive solution of the model,and co...In this paper,based on the SVIQR model we develop a stochastic epidemic model with multiple vaccinations and time delay.Firstly,we prove the existence and uniqueness of the global positive solution of the model,and construct suitable functions to obtain sufficient conditions for disease extinction.Secondly,in order to effectively control the spread of the disease,appropriate control strategies are formulated by using optimal control theory.Finally,the results are verified by numerical simulation.展开更多
Edo-period historical records and documents preserved a substantial number of images,many of which are related to epidemic outbreaks.Through systematic collation and categorical analysis,this study uses the chronologi...Edo-period historical records and documents preserved a substantial number of images,many of which are related to epidemic outbreaks.Through systematic collation and categorical analysis,this study uses the chronological and thematic characteristics of these images as a framework to examine the response mechanisms of the Japanese government and public during infectious disease pandemics in the Edo period,as well as the multidimensional impacts of epidemics on social economy,culture,and customs.Illustrations of smallpox in medical texts reveal the developmental trajectory of Japan’s traditional medical knowledge system,while drawings in essays and diaries reflect public fear and non-medical cognitive patterns during cholera outbreaks.Epidemic-themed paintings not only document cholera treatment protocols by the government and medical professionals,as well as grassroots prevention and treatment practices for measles,but also vividly depict social dynamics during crises.Images related to epidemics in advertising reflect the prosperity of the pharmaceutical industry in the Edo period,while depictions in folding screens,ukiyozoushi and the occupational illustrations demonstrate societal customs for epidemic response.Collectively,the Edo-period epidemic crises profoundly shaped Japan’s medical system,economic structure,cultural forms,folk traditions,and public psychology,prompting the government,medical professionals,and civilians to develop distinct era-specific social coping mechanisms.展开更多
This paper investigates a new SEIQR(susceptible–exposed–infected–quarantined–recovered) epidemic model with quarantine mechanism on heterogeneous complex networks. Firstly, the nonlinear SEIQR epidemic spreading d...This paper investigates a new SEIQR(susceptible–exposed–infected–quarantined–recovered) epidemic model with quarantine mechanism on heterogeneous complex networks. Firstly, the nonlinear SEIQR epidemic spreading dynamic differential coupling model is proposed. Then, by using mean-field theory and the next-generation matrix method, the equilibriums and basic reproduction number are derived. Theoretical results indicate that the basic reproduction number significantly relies on model parameters and topology of the underlying networks. In addition, the globally asymptotic stability of equilibrium and the permanence of the disease are proved in detail by the Routh–Hurwitz criterion, Lyapunov method and La Salle's invariance principle. Furthermore, we find that the quarantine mechanism, that is the quarantine rate(γ1, γ2), has a significant effect on epidemic spreading through sensitivity analysis of basic reproduction number and model parameters. Meanwhile, the optimal control model of quarantined rate and analysis method are proposed, which can optimize the government control strategies and reduce the number of infected individual. Finally, numerical simulations are given to verify the correctness of theoretical results and a practice application is proposed to predict and control the spreading of COVID-19.展开更多
The outbreak of COVID-19 in 2019 has made people pay more attention to infectious diseases.In order to reduce the risk of infection and prevent the spread of infectious diseases,it is crucial to strengthen individual ...The outbreak of COVID-19 in 2019 has made people pay more attention to infectious diseases.In order to reduce the risk of infection and prevent the spread of infectious diseases,it is crucial to strengthen individual immunization measures and to restrain the diffusion of negative information relevant to vaccines at the opportune moment.This study develops a three-layer coupling model within the framework of hypernetwork evolution,examining the interplay among negative information,immune behavior,and epidemic propagation.Firstly,the dynamic topology evolution process of hypernetwork includes node joining,aging out,hyperedge adding and reconnecting.The three-layer communication model accounts for the multifaceted influences exerted by official media channels,subjective psychological acceptance capabilities,self-identification abilities,and physical fitness levels.Each level of the decision-making process is described using the Heaviside step function.Secondly,the dynamics equations of each state and the prevalence threshold are derived using the microscopic Markov chain approach(MMCA).The results show that the epidemic threshold is affected by three transmission processes.Finally,through the simulation testing,it is possible to enhance the intensity of official clarification,improve individual self-identification ability and physical fitness,and thereby promote the overall physical enhancement of society.This,in turn,is beneficial in controlling false information,heightening vaccination coverage,and controlling the epidemic.展开更多
This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward...This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward spreading speeds for the infective individuals, which can be used to estimate how fast the disease spreads. To overcome the difficulty arising from the lack of comparison principle for such time-space periodic nonmonotone systems, our proof is mainly based on constructing a series of scalar time-space periodic equations, establishing the spreading speeds for such auxiliary equations and using comparison methods. It may be the first work to study the spreading speed for time-space periodic non-monotone systems.展开更多
During the epidemics in the Qing dynasty,many medical professionals,nonprofessionals,and social organizations collected and sorted medical prescriptions related to infectious diseases.These people also compiled,publis...During the epidemics in the Qing dynasty,many medical professionals,nonprofessionals,and social organizations collected and sorted medical prescriptions related to infectious diseases.These people also compiled,published,disseminated,and consulted related medical formularies.The above historical event can be viewed as the construction and dissemination of medical knowledge.They edited and published medical formularies on infectious diseases with lower cost and in flexible ways by taking the initiative and giving full scope to creativity.Diverse anti-epidemic medical prescriptions from these medical formularies can be used for infectious diseases in the event of the outbreaks.However,the therapeutic effects of classical prescriptions and folk recipes cannot be regarded as the same.The wide circulation of anti-epidemic medical prescriptions and medical formularies was essentially a process of epidemic prevention resource allocation.Not only did it enable many nonprofessionals to participate in epidemic prevention and control,but it also enhanced awareness,knowledge,and capacity for epidemic prevention at the individual level.At the same time,due to the uneven quality and individual differences in the physical fitness and condition of the prescriptions and formularies,they had the capacity of causing inconveniences to the readers or patients.展开更多
[ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of sing...[ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of single application of virus in-hibitors and composite application of virus inhibitors with seed dressing agents and pesticides on maize rough dwarf disease in different areas with varying epidemic intensity were investigated. [Result] The same treatment possessed entirely different effects in severely affected areas and slightly affected areas. To be specific, single application of virus inhibitors in slightly affected areas exhibited good control effects, with a control efficiency of 76.59% and yield increment rate of 158.21%; in severely affected areas, single application of virus inhibitors led to low control efficiency and yield increment rate. The highest control efficiency of composite application of virus inhibitors with seed dressing agents and pesticides in severely affected areas was 71.38%, and experimental plots changed from total crop failure to have certain eco-nomic output. [Conclusion] ln different areas with varying epidemic intensity of maize rough dwarf disease, different application modes should be adopted according to lo-cal conditions, thereby saving cost and improving control efficiency.展开更多
基金supported by the National Key Research and Development Program of China(Project No.2023YFC2307500).
文摘Influenza,an acute respiratory infectious disease caused by the influenza virus,exhibits distinct seasonal patterns in China,with peak activity occurring in winter and spring in northern regions,and in winter and summer in southern areas[1].The World Health Organization(WHO)emphasizes that early warning and epidemic intensity assessments are critical public health strategies for influenza prevention and control.Internet-based flu surveillance,with real-time data and low costs,effectively complements traditional methods.The Baidu Search Index,which reflects flu-related queries,strongly correlates with influenza trends,aiding in regional activity assessment and outbreak tracking[2].
基金Supported by National Natural Science Foundation of China(61911530398,12231012)Consultancy Project by the Chinese Academy of Engineering(2022-JB-06,2023-JB-12)+3 种基金the Natural Science Foundation of Fujian Province of China(2021J01621)Special Projects of the Central Government Guiding Local Science and Technology Development(2021L3018)Royal Society of Edinburgh(RSE1832)Engineering and Physical Sciences Research Council(EP/W522521/1).
文摘A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.
基金supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University(IMSIU)(grant number IMSIU-DDRSP2501).
文摘The numerical approximation of stochastic partial differential equations(SPDEs),particularly those including q-diffusion,poses considerable challenges due to the requirements for high-order precision,stability amongst random perturbations,and processing efficiency.Because of their simplicity,conventional numerical techniques like the Euler-Maruyama method are frequently employed to solve stochastic differential equations;nonetheless,they may have low-order accuracy and lower stability in stiff or high-resolution situations.This study proposes a novel computational scheme for solving SPDEs arising from a stochastic SEIR model with q-diffusion and a general incidence rate function.A proposed computational scheme can be used to solve stochastic partial differential equations.For spatial discretization,a compact scheme is chosen.The compact scheme can provide a sixth-order accurate solution.The proposed scheme can be considered an extension of the Euler Maruyama method.Stability and consistency in the mean square sense are also provided.For application purposes,the stochastic SEIR model is considered using q-diffusion effects.The scheme is used to solve the stochastic model and compared with the Euler-Maruyama method.The scheme is also compared with nonstandard finite difference method for solving deterministic models.In both cases,it performs better than existing schemes.Incorporating q-diffusion further enhanced the model’s ability to represent realistic spatial-temporal disease dynamics,especially in scenarios where classical diffusion is insufficient.
基金Project supported by the National Natural Science Foundation of China (Grant No. 72174121)the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, and the Soft Science Research Project of Shanghai (Grant No. 22692112600)。
文摘Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt protective measures.However, whether to disseminate specific information is also a behavioral decision. In light of this understanding, we develop a coupled information–vaccination–epidemic model to depict these co-evolutionary dynamics in a three-layer network. Negative information dissemination and vaccination are treated as separate decision-making processes. We then examine the combined effects of herd and risk motives on information dissemination and vaccination decisions through the lens of game theory. The microscopic Markov chain approach(MMCA) is used to describe the dynamic process and to derive the epidemic threshold. Simulation results indicate that increasing the cost of negative information dissemination and providing timely clarification can effectively control the epidemic. Furthermore, a phenomenon of diminishing marginal utility is observed as the cost of dissemination increases, suggesting that authorities do not need to overinvest in suppressing negative information. Conversely, reducing the cost of vaccination and increasing vaccine efficacy emerge as more effective strategies for outbreak control. In addition, we find that the scale of the epidemic is greater when the herd motive dominates behavioral decision-making. In conclusion, this study provides a new perspective for understanding the complexity of epidemic spreading by starting with the construction of different behavioral decisions.
基金supported by the National Natural Science Foundation of China(U23A20236)the Key Research and Development Program,Guidance Projects of Heilongjiang Province,China(GZ20220029)。
文摘The host intestinal microbiota has emerged as the third element in the interactions between hosts and enteric viruses,and potentially affects the infection processes of enteric viruses.However,the interaction of porcine enteric coronavirus with intestinal microorganisms during infection remains unclear.In this study,we used 16S-rRNA-based Illumina NovaSeq high-throughput sequencing to identify the changes in the intestinal microbiota of piglets mediated by porcine epidemic diarrhea virus(PEDV)infection and the effects of the alterations in intestinal bacteria on PEDV infection and its molecular mechanisms.The intestinal microbiota of PEDV-infected piglets had significantly less diversity than the healthy group and different bacterial community characteristics.Among the altered intestinal bacteria,the relative abundance of Clostridium perfringens was significantly increased in the PEDV-infected group.A strain of C.perfringens type A,named DQ21,was successfully isolated from the intestines of healthy piglets.The metabolites of swine C.perfringens type A strain DQ21 significantly enhanced PEDV replication in porcine intestinal epithelial cell clone J2(IPEC-J2)cells,and PEDV infection and pathogenicity in suckling piglets.Palmitic acid(PA)was identified as one of those metabolites with metabolomic technology,and significantly enhanced PEDV replication in IPEC-J2 cells and PEDV infection and pathogenicity in suckling piglets.PA also increased the neutralizing antibody titer in the immune sera of mice.Furthermore,PA mediated the palmitoylation of the PEDV S protein,which improved virion stability and membrane fusion,thereby enhancing viral infection.Overall,our study demonstrates a novel mechanism of PEDV infection,with implications for PEDV pathogenicity.
基金funded by grants from the National Key R&D Program of China(2023YFD1800304)the National Natural Science Foundation of China to QZ(32273041)+1 种基金the Natural Science Foundation of Shaanxi Province of China(2022JC-12)the Central Public interest Scientific Institution Basal Research Fund,National Data Center of Animal Health.
文摘Porcine epidemic diarrhea(PED),caused by porcine epidemic diarrhea virus(PEDV),can induce 80–100%mortality in newborn piglets;therefore,specific and rapid detection methods are important for the prevention of this viral infection.In particular,methods for detecting neutralizing antibodies(nAbs)can be used to evaluate the immunization effect of PEDV vaccines.The spike protein of PEDV(PEDV-S)has been universally used as an antigen to develop immunoassays to detect nAbs.Nanobodies(Nbs)offer advantages such as ease of genetic engineering and low production costs,making them promising for diagnostic applications.In this study,PEDV-S was expressed via the baculovirus system and was used as an antigen to immunize Bactrian camels.A total of 10 Nbs against PEDV-S were first screened and expressed as fusion proteins with horseradish peroxidase(HRP)in HEK293T cells.A Nb-HRP fusion protein named PEDV-S-Nb13-HRP was subsequently selected and used as a probe for developing a competitive enzyme-linked immunosorbent assay(cELISA)to detect anti-PEDV nAbs.Optimization assays identified 80 ng/well of PEDV-S as the optimal coating antigen concentration.The optimal dilution of PEDV-S-Nb13-HRP was 1:200,and the optimal serum dilution was 1:10.The cutoff value of cELISA was determined as 28.1%,demonstrating high specificity,repeatability,stability,and good agreement rates with two commercial ELISA kits(93.6%)and a serum neutralization test(96.34%).Additionally,the results of the detection of IgA antibodies in oral and milk samples from sows were in good agreement with those of the IDEXX PEDV IgA kit.These results demonstrate that the cELISA is a reliable and cost-effective method for detecting anti-PEDV nAbs.
基金supported by the Basic Research Innovation Group Project of Gansu Province(No.25JRRA434)the National Natural Science Foundation of China(U22A20522).
文摘The cross-species infection of coronaviruses has resulted in several major epidemics since 2003.Porcine epidemic diarrhea virus(PEDV)is a devastating swine enteric coronavirus,which targets pigs as the only natural reservoir.In this study,the nucleic acid of PEDV was detected in rat fecal samples collected from pig farms.Further animal tests showed that PEDV can cause systemic infections in neonatal mice and rats via intracranial inoculation.The brain,lung,intestine and spleen were all targets for PEDV in rodents in contrast to the intestine being targeted in pigs.Morbidity and mortality vary via different infection routes.PEDV was also detectable in feces after infection,suggesting that the infected rodents were potential infectious sources.Moreover,the cerebral tropism of PEDV was verified in piglets via orally inoculation,which had not been identified before.In conclusion,our findings demonstrate that PEDV could cross the species barrier to infect mice and rats through different routes in experimental settings.Although it is highly devastating to piglets,PEDV changes the target organs and turns to be milder when meeting with new hosts.Based on these findings,more attention should be paid to the potential cross-species infection of PEDV.
基金supported by a grant from the National Key Research and Development Plans of China(No.2021YFD1800401)to Zhe Wangthe National Natural Science Foundation of China(No.32070128)to Zhe Wang+5 种基金the Shanghai Biomedical Science and Technology Support Special Project(No.21S11900200)to Zhe Wangthe National Natural Science Foundation of China(No.31472211)to ZhiBiao Yangthe Natural Science Foundation of Shanghai(No.21ZR1433900)to Zhibiao Yangthe National Key Research and Development Program of China(No.2022YFD1800805)to Yanjun Zhouthe Pinduoduo-China Agricultural University Research Fund(PC2024A01003)to Xiangfeng Wangthe Biomedicine and Technology Supporting Project of the Shanghai Science and Technology Innovation Plan(Grant No.22S11902200,China)to Tao Sun.
文摘Porcine epidemic diarrhea virus(PEDV)infection causes acute watery diarrhea in neonatal piglets,leading to substantial economic losses within the pig farming industry.This study demonstrates that clofazimine(CFZ)significantly inhibits PEDV replication in a dose-dependent manner in vitro,with negligible cytotoxicity.Findings from our time-of-addition assays indicate that CFZ effectively disrupts multiple stages of the viral infection cycle.Using a CoV-RdRp-Gluc reporter system,we evaluated the potency of CFZ against PEDV RNA-dependent RNA polymerase(RdRp),and determined a low IC50 value of 0.1364μM.Molecular docking studies further confirmed that CFZ has high binding affinity at the active sites of the spike protein and RdRp protein in PEDV.Transcriptome analysis of Vero E6 cells,with and without CFZ treatment,revealed a significant change in transcriptional activity at 8 h postinfection(hpi).Moreover,the simultaneous application of CFZ and nucleoside analogs showed enhanced the anti-PEDV effect of CFZ in vitro.Our study underscores the potential of CFZ as a viable therapeutic agent against PEDV.
基金supported by the Fundamental Research Funds for the Central Universities(No.3122025090)。
文摘In this paper,based on the SVIQR model we develop a stochastic epidemic model with multiple vaccinations and time delay.Firstly,we prove the existence and uniqueness of the global positive solution of the model,and construct suitable functions to obtain sufficient conditions for disease extinction.Secondly,in order to effectively control the spread of the disease,appropriate control strategies are formulated by using optimal control theory.Finally,the results are verified by numerical simulation.
基金financed by the grant from the Major Project of the National Social Science Fund of China(No.20&ZD222).
文摘Edo-period historical records and documents preserved a substantial number of images,many of which are related to epidemic outbreaks.Through systematic collation and categorical analysis,this study uses the chronological and thematic characteristics of these images as a framework to examine the response mechanisms of the Japanese government and public during infectious disease pandemics in the Edo period,as well as the multidimensional impacts of epidemics on social economy,culture,and customs.Illustrations of smallpox in medical texts reveal the developmental trajectory of Japan’s traditional medical knowledge system,while drawings in essays and diaries reflect public fear and non-medical cognitive patterns during cholera outbreaks.Epidemic-themed paintings not only document cholera treatment protocols by the government and medical professionals,as well as grassroots prevention and treatment practices for measles,but also vividly depict social dynamics during crises.Images related to epidemics in advertising reflect the prosperity of the pharmaceutical industry in the Edo period,while depictions in folding screens,ukiyozoushi and the occupational illustrations demonstrate societal customs for epidemic response.Collectively,the Edo-period epidemic crises profoundly shaped Japan’s medical system,economic structure,cultural forms,folk traditions,and public psychology,prompting the government,medical professionals,and civilians to develop distinct era-specific social coping mechanisms.
基金Project supported the Natural Science Foundation of Zhejiang Province, China (Grant No. LQN25F030011)the Fundamental Research Project of Hangzhou Dianzi University (Grant No. KYS065624391)+1 种基金the National Natural Science Foundation of China (Grant No. 61573148)the Science and Technology Planning Project of Guangdong Province, China (Grant No. 2019A050520001)。
文摘This paper investigates a new SEIQR(susceptible–exposed–infected–quarantined–recovered) epidemic model with quarantine mechanism on heterogeneous complex networks. Firstly, the nonlinear SEIQR epidemic spreading dynamic differential coupling model is proposed. Then, by using mean-field theory and the next-generation matrix method, the equilibriums and basic reproduction number are derived. Theoretical results indicate that the basic reproduction number significantly relies on model parameters and topology of the underlying networks. In addition, the globally asymptotic stability of equilibrium and the permanence of the disease are proved in detail by the Routh–Hurwitz criterion, Lyapunov method and La Salle's invariance principle. Furthermore, we find that the quarantine mechanism, that is the quarantine rate(γ1, γ2), has a significant effect on epidemic spreading through sensitivity analysis of basic reproduction number and model parameters. Meanwhile, the optimal control model of quarantined rate and analysis method are proposed, which can optimize the government control strategies and reduce the number of infected individual. Finally, numerical simulations are given to verify the correctness of theoretical results and a practice application is proposed to predict and control the spreading of COVID-19.
文摘The outbreak of COVID-19 in 2019 has made people pay more attention to infectious diseases.In order to reduce the risk of infection and prevent the spread of infectious diseases,it is crucial to strengthen individual immunization measures and to restrain the diffusion of negative information relevant to vaccines at the opportune moment.This study develops a three-layer coupling model within the framework of hypernetwork evolution,examining the interplay among negative information,immune behavior,and epidemic propagation.Firstly,the dynamic topology evolution process of hypernetwork includes node joining,aging out,hyperedge adding and reconnecting.The three-layer communication model accounts for the multifaceted influences exerted by official media channels,subjective psychological acceptance capabilities,self-identification abilities,and physical fitness levels.Each level of the decision-making process is described using the Heaviside step function.Secondly,the dynamics equations of each state and the prevalence threshold are derived using the microscopic Markov chain approach(MMCA).The results show that the epidemic threshold is affected by three transmission processes.Finally,through the simulation testing,it is possible to enhance the intensity of official clarification,improve individual self-identification ability and physical fitness,and thereby promote the overall physical enhancement of society.This,in turn,is beneficial in controlling false information,heightening vaccination coverage,and controlling the epidemic.
基金supported by the Natural Science Basic Research Program of Shanxi(Grant No.2024JC-YBMS-025)the Innovation Capability Support Program of Shanxi(Grant No.2024RS-CXTD-88)。
文摘This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward spreading speeds for the infective individuals, which can be used to estimate how fast the disease spreads. To overcome the difficulty arising from the lack of comparison principle for such time-space periodic nonmonotone systems, our proof is mainly based on constructing a series of scalar time-space periodic equations, establishing the spreading speeds for such auxiliary equations and using comparison methods. It may be the first work to study the spreading speed for time-space periodic non-monotone systems.
基金financially supported by the National Social Science Foundation of China(No.ZDA175)the Humanities and Social Science Foundation of the Ministry of Education(No.20YJC770021)。
文摘During the epidemics in the Qing dynasty,many medical professionals,nonprofessionals,and social organizations collected and sorted medical prescriptions related to infectious diseases.These people also compiled,published,disseminated,and consulted related medical formularies.The above historical event can be viewed as the construction and dissemination of medical knowledge.They edited and published medical formularies on infectious diseases with lower cost and in flexible ways by taking the initiative and giving full scope to creativity.Diverse anti-epidemic medical prescriptions from these medical formularies can be used for infectious diseases in the event of the outbreaks.However,the therapeutic effects of classical prescriptions and folk recipes cannot be regarded as the same.The wide circulation of anti-epidemic medical prescriptions and medical formularies was essentially a process of epidemic prevention resource allocation.Not only did it enable many nonprofessionals to participate in epidemic prevention and control,but it also enhanced awareness,knowledge,and capacity for epidemic prevention at the individual level.At the same time,due to the uneven quality and individual differences in the physical fitness and condition of the prescriptions and formularies,they had the capacity of causing inconveniences to the readers or patients.
基金Supported by National Public Welfare Industry Research Project of China(201003031)Science and Technology Development Program of Shandong Province(2009GG10009015)Agricultural Science and Technology Innovation Program of Jinan City(201302637-1)~~
文摘[ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of single application of virus in-hibitors and composite application of virus inhibitors with seed dressing agents and pesticides on maize rough dwarf disease in different areas with varying epidemic intensity were investigated. [Result] The same treatment possessed entirely different effects in severely affected areas and slightly affected areas. To be specific, single application of virus inhibitors in slightly affected areas exhibited good control effects, with a control efficiency of 76.59% and yield increment rate of 158.21%; in severely affected areas, single application of virus inhibitors led to low control efficiency and yield increment rate. The highest control efficiency of composite application of virus inhibitors with seed dressing agents and pesticides in severely affected areas was 71.38%, and experimental plots changed from total crop failure to have certain eco-nomic output. [Conclusion] ln different areas with varying epidemic intensity of maize rough dwarf disease, different application modes should be adopted according to lo-cal conditions, thereby saving cost and improving control efficiency.