BACKGROUND The emergence of the Omicron variant(B.1.1.529)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)raised global concerns with its highly transmissible nature.AIM To investigate the genomic,clinic...BACKGROUND The emergence of the Omicron variant(B.1.1.529)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)raised global concerns with its highly transmissible nature.AIM To investigate the genomic,clinical,and demographic characteristics of Omicron infections within the early outbreak cluster in western part of Sri Lanka.METHODS We analyzed sequence data from January 2022 to April 2022 to understand variant dynamics,clinical presentation,and demographic associations.RESULTS Whole-genome sequencing of 85 nasopharyngeal and throat swab samples collected in western part of Sri Lanka between January and April 2022 identified 70(82.34%)of it as Omicron variants.BA.2 was the most prevalent sub-lineage(57%),followed by BA.1.1(14.20%)and majority of them were from>12 years old individuals.Phylogenetic analysis revealed clustering into four distinct clades(21I,21K,21L,and 21M),suggesting potential differences in transmission chains or evolutionary pressures.CONCLUSION This study found BA.2 to be the predominant Omicron sub-lineage in the western part of Sri Lanka during the first quarter of 2022,aligning with global trends.Phylogenetic analysis revealed diverse introductions and local transmission.Continued genomic surveillance and robust public health measures remain crucial for managing the evolving SARS-CoV-2 landscape.展开更多
BACKGROUND In tropical Asia,arbovirus-induced encephalitis continues to be a serious public health issue.Encephalitis is caused by wide range of neurotropic pathogens,and flaviviruses are one of the main causative age...BACKGROUND In tropical Asia,arbovirus-induced encephalitis continues to be a serious public health issue.Encephalitis is caused by wide range of neurotropic pathogens,and flaviviruses are one of the main causative agents in the area.Sri Lanka reports a considerable number of central nervous system infections annually.Both dengue and Japanese encephalitis are endemic,and cases of Zika and West Nile virus infections were reported occasionally in Sri Lanka.Although reported number of Japanese encephalitis cases has reduced in the past,aetiological diagnosis in majority of encephalitis cases is still unknown.AIM To detect dengue virus(DENV)infections in individuals in the central region of Sri Lanka who were clinically suspected of having encephalitis.METHODS A retrospective observational analysis was conducted on 99 cerebrospinal fluid samples received to a virology laboratory from patients in the central part of Sri Lanka who were clinically suspected of having encephalitis.Samples were analyzed using reverse transcriptase polymerase chain reaction(RT-PCR)with universal flavivirus primers to detect flaviviral RNA followed by DENV serotyping real-time RT-PCR,and an immunoglobulin M(IgM)detection enzyme-linked immunosorbent assay to detect IgM antibodies indicative of a possible recent DENV infection.RESULTS DENV aetiology was detected in 6(6.06%)cerebrospinal fluid samples,and all were confirmed as DENV infections.A single positive result(1.01%)was yielded through RT-PCR and was identified as DENV serotype 3.Serology testing detected 05(5.05%)anti-dengue IgM positives and further investigation indicated probable DENV aetiology.Among positives 02(33.33%)were children(aged less than 14 years),and rest were adults.CONCLUSION These findings underscore the presence of DENV-associated central nervous system infections and highlight the need for broader surveillance and more advanced diagnostic approaches in the future.展开更多
文摘BACKGROUND The emergence of the Omicron variant(B.1.1.529)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)raised global concerns with its highly transmissible nature.AIM To investigate the genomic,clinical,and demographic characteristics of Omicron infections within the early outbreak cluster in western part of Sri Lanka.METHODS We analyzed sequence data from January 2022 to April 2022 to understand variant dynamics,clinical presentation,and demographic associations.RESULTS Whole-genome sequencing of 85 nasopharyngeal and throat swab samples collected in western part of Sri Lanka between January and April 2022 identified 70(82.34%)of it as Omicron variants.BA.2 was the most prevalent sub-lineage(57%),followed by BA.1.1(14.20%)and majority of them were from>12 years old individuals.Phylogenetic analysis revealed clustering into four distinct clades(21I,21K,21L,and 21M),suggesting potential differences in transmission chains or evolutionary pressures.CONCLUSION This study found BA.2 to be the predominant Omicron sub-lineage in the western part of Sri Lanka during the first quarter of 2022,aligning with global trends.Phylogenetic analysis revealed diverse introductions and local transmission.Continued genomic surveillance and robust public health measures remain crucial for managing the evolving SARS-CoV-2 landscape.
文摘BACKGROUND In tropical Asia,arbovirus-induced encephalitis continues to be a serious public health issue.Encephalitis is caused by wide range of neurotropic pathogens,and flaviviruses are one of the main causative agents in the area.Sri Lanka reports a considerable number of central nervous system infections annually.Both dengue and Japanese encephalitis are endemic,and cases of Zika and West Nile virus infections were reported occasionally in Sri Lanka.Although reported number of Japanese encephalitis cases has reduced in the past,aetiological diagnosis in majority of encephalitis cases is still unknown.AIM To detect dengue virus(DENV)infections in individuals in the central region of Sri Lanka who were clinically suspected of having encephalitis.METHODS A retrospective observational analysis was conducted on 99 cerebrospinal fluid samples received to a virology laboratory from patients in the central part of Sri Lanka who were clinically suspected of having encephalitis.Samples were analyzed using reverse transcriptase polymerase chain reaction(RT-PCR)with universal flavivirus primers to detect flaviviral RNA followed by DENV serotyping real-time RT-PCR,and an immunoglobulin M(IgM)detection enzyme-linked immunosorbent assay to detect IgM antibodies indicative of a possible recent DENV infection.RESULTS DENV aetiology was detected in 6(6.06%)cerebrospinal fluid samples,and all were confirmed as DENV infections.A single positive result(1.01%)was yielded through RT-PCR and was identified as DENV serotype 3.Serology testing detected 05(5.05%)anti-dengue IgM positives and further investigation indicated probable DENV aetiology.Among positives 02(33.33%)were children(aged less than 14 years),and rest were adults.CONCLUSION These findings underscore the presence of DENV-associated central nervous system infections and highlight the need for broader surveillance and more advanced diagnostic approaches in the future.
