Molecular epidemiology and genetic diversity of norovirus infection in children with acute gastroenteritis in Bangladesh, 2014-2019.

Acute gastroenteritis (AGE) is one of the most common diseases in children, and it continues to be a significant cause of morbidity and mortality worldwide. Norovirus is one of the major enteropathogens associated with both sporadic diarrhea and outbreaks of gastroenteritis. This study aims to investigate genotype diversity and molecular epidemiology of norovirus in Bangladesh. A total of 466 fecal specimens were collected from January 2014 to January 2019 from children below 5 years old with AGE in Bangladesh. All samples were analyzed by reverse transcriptase polymerase chain reaction to detect norovirus, and sequence analysis was conducted if found positive. Norovirus was detected in 5.1% (24 of 466) fecal specimens. Norovirus genotype GII.7 was predominant (62.5%, 15 of 24), followed by GII.3 (37.5%, 9 of 24). Coinfection between rotavirus and norovirus was found in 7 of 24 positive cases. Diarrhea (93.7%) and dehydration (89%) were the most common symptoms in children with AGE. About 80% of the positive cases were detected in children aged under 24 months. One seasonal peak (87.5% infection) was detected in the winter. This study suggests that norovirus continues to be one of the major etiologies of children AGE in Bangladesh. This study will provide a guideline to assess the burden of norovirus infection in Bangladesh, which will assist to combat against AGE.

Impact of population density and weather on COVID-19 pandemic and SARS-CoV-2 mutation frequency in Bangladesh.

Coronavirus disease-2019 (COVID-19) has caused the recent pandemic worldwide. Research studies are focused on various factors affecting the pandemic to find effective vaccine or therapeutics against COVID-19. Environmental factors are the important regulators of COVID-19 pandemic. This study aims to determine the impact of weather on the COVID-19 cases, fatalities and frequency of mutations in Bangladesh. The impacts were determined on 1, 7 and 14 days of the case. The study was conducted based on Spearman's correlation coefficients. The highest correlation was found between population density and cases (rs = 0.712). Among metrological parameters, average temperature had the strongest correlation (rs = -0.675) with the cases. About 82% of Bangladeshi isolates had D614G at spike protein. Both temperature and UV index had strong effects on the frequency of mutations. Among host factors, coinfection is highly associated with frequency of different mutations. This study will give a complete picture of the effects of metrological parameters on COVID-19 cases, fatalities and mutation frequency that will help the authorities to take proper decisions.

Impact of meteorological parameters and population density on variants of SARS-CoV-2 and outcome of COVID-19 pandemic in Japan.

Although vaccines have become available, emergence and rapid transmission of new variants have added new paradigm in the coronavirus disease-2019 (COVID-19) pandemic. Weather, population and host immunity have been detected as the regulatory elements of COVID-19. This study aims to investigate the effects of weather, population and host factors on the outcome of COVID-19 and mutation frequency in Japan. Data were collected during January 2020 to February 2021. About 92% isolates were form GR clades. Variants 501Y.V1 (53%) and 452R.V1 (24%) were most prevalent in Japan. The strongest correlation was detected between fatalities and population density (rs = 0.81) followed by total population (rs = 0.72). Relative humidity had the highest correlation (rs = -0.71) with the case fatality rate. Cluster mutations namely N501Y (45%), E484K (30%), N439K (16%), K417N (6%) and T478I (3%) at spike protein have increased during January to February 2021. Above 90% fatality was detected in patients aged >60 years. The ratio of male to female patients of COVID-19 was 1.35:1. This study will help to understand the seasonality of COVID-19 and impact of weather on the outcome which will add knowledge to reduce the health burden of COVID-19 by the international organisations and policy makers.

Molecular and epidemiological trends of human bocavirus and adenovirus in children with acute gastroenteritis in Bangladesh during 2015 to 2019.

Virus associated diarrhea remains one of the leading causes of children morbidity and mortality in Bangladesh. Human bocavirus (HBoV) has been reported as a potential pathogen of children's diarrhea worldwide. However, due to its frequent association with other gastroenteric pathogens, its role as diarrhea causative agent remains to be defined. This study focuses to detect the incidence of HBoV and adenovirus (AdV) and to determine the molecular and epidemiological characteristics of HBoV and AdV. Between January 2015 to January 2019, 290 fecal specimens were collected from diarrheal children in Bangladesh. All fecal specimens were tested for HBoV and AdV by conventional polymerase chain reaction and sequencing methods. HBoV was detected in 7.24% (21 of 290) of the stool samples, as a sole virus in 71.42% (15 of 21) of the positive samples. AdV was detected in 4.82% (14 of 290) of the samples. The most common clinical symptoms of HBoV infected patients were diarrhea (100%) and vomiting (57%). All of the isolates of HBoV were from HBoV1 and AdV were from AdV41, AdV5, AdV7, and AdV8. To the best of our knowledge, this is the first epidemiological and molecular analysis report of HBoV from clinical specimens in Bangladesh. In the future, more studies are needed to clarify the role of HBoV as diarrheal pathogens.

The Epidemiologic and Clinical Characteristics of the 2023 Dengue Outbreak in Bangladesh.

The ongoing 2023 dengue outbreak is the worst ever case reported in Bangladesh. There is a lack of epidemiological studies on the outbreak. A 2-tailed t test was performed. Multivariable logistic regression analysis was conducted. We found about 277 801 cases and 1393 deaths from the 2023 dengue outbreak. About 52% of the cases were from outside of Dhaka. The male:female ratio was about 3:2. The highest frequency of cases was found among people aged 19-29 years (28.7%, 79 673 of 277 801; P = .001). The overall case fatality rate (CFR) was 0.5%. The highest CFR was found among children aged 0-10 years (12%). Fever (99%) was the most prevalent, followed by joint pain (86%). We found significantly higher odds of fatalities (adjusted odds ratio [aOR], 4.21; 95% CI, 3.93-4.74; P = .05), cases (aOR, 3.85; 95% CI, 3.25-4.12; P = .001) and hospitalizations (aOR, 3.26; 95% CI, 3.11-4.04; P = .006) during the 2023 outbreak compared with previous outbreaks during 2008-2022. This is one of the early reports of epidemiological and clinical characteristics of ongoing dengue outbreak.

Epidemiology of mpox: Focus on men with HIV.

The 2022 mpox outbreak is the first ever report of worldwide spread of cases. Integrated knowledge on the epidemiology and clinical characteristics of mpox are limited. This study was conducted to shed light on the epidemiology of 2022 mpox outbreak. We found that men were the most infected sex (90-100 % cases). The highest prevalence of mpox infection (70 %) was found among men aged between 30 and 40 years. Pre-existing HIV was reported among 24-100 % of mpox positive cases. About 90-100 % of the cases have been disproportionately found among group of men with specific sexual practice, namely, men who have sex with men (MSM). Case fatality rate of 2022 mpox outbreak varied between 1 and 10 %. Studies on the relationship of HIV with mpox outcomes are limited. This study will add knowledge on the epidemiology of 2022 mpox outbreak.

Impact of meteorological factors and population density on COVID-19 pandemic in Saudi Arabia.

Transmission and increase in cases and fatalities of coronavirus disease-2019 (COVID-19) are significantly influenced by the parameters of weather, human activities and population factors. However, study gap on the seasonality of COVID-19 and impact of environmental factors on the pandemic in Saudi Arabia is present. The main aim of the study is to evaluate the impact of environment on the COVID-19 pandemic. Data were analyzed from January 2020 to July 2021. The generalized estimating equation (GEE) was used to determine the effect of environmental variables on longitudinal outcomes. Spearman's rank correlation coefficient (rs ) was used to analyze the impact of different parameters on the outcome of the pandemic. Multiple sequence alignment was performed by using ClustalW. Vaccination and fatalities (r s = -0.85) had the highest association followed by vaccination with cases (r s = -0.81) and population density with the fatalities (rs  = 0.71). The growth rate had the highest correlation with sun hours (r s = -0.63). Isolates from variant of concern alpha and beta were detected. Most of the reference sequences in Saudi Arabia were closely related with B.1.427/429 variant. Clade GH (54%) was the most prevalent followed by O (27%), GR (9%), G (6%), and S (4%), respectively. Male to female patient ratio was 1.4:1. About 95% fatality and hospitalization were reported in patients aged >60 years. This study will create a comprehensive insight of the interaction of environmental factors and the pandemic and add knowledge on seasonality of COVID-19 in Saudi Arabia.

Prevalence and genetic diversity of rotavirus in Bangladesh during pre-vaccination period, 1973-2023: a meta-analysis.

Introduction: Rotavirus infection is a major cause of mortality among children under 5 years in Bangladesh. There is lack of integrated studies on rotavirus prevalence and genetic diversity during 1973 to 2023 in Bangladesh. Methods: This meta-analysis was conducted to determine the prevalence, genotypic diversity and seasonal distribution of rotavirus during pre-vaccination period in Bangladesh. This study included published articles on rotavirus A, rotavirus B and rotavirus C. We used Medline, Scopus and Google Scholar for published articles. Selected literatures were published between 1973 to 2023. Results: This study detected 12431 research articles published on rotavirus. Based on the inclusion criteria, 29 of 75 (30.2%) studies were selected. Molecular epidemiological data was taken from 29 articles, prevalence data from 29 articles, and clinical symptoms from 19 articles. The pooled prevalence of rotavirus was 30.1% (95% CI: 22%-45%, p = 0.005). Rotavirus G1 (27.1%, 2228 of 8219) was the most prevalent followed by G2 (21.09%, 1733 of 8219), G4 (11.58%, 952 of 8219), G9 (9.37%, 770 of 8219), G12 (8.48%, 697 of 8219), and G3 (2.79%, 229 of 8219), respectively. Genotype P[8] (40.6%, 2548 of 6274) was the most prevalent followed by P[4] (12.4%, 777 of 6274) and P[6] (6.4%, 400 of 6274), respectively. Rotavirus G1P[8] (19%) was the most frequent followed by G2P [4] (9.4%), G12P[8] (7.2%), and G9P[8], respectively. Rotavirus infection had higher odds of occurrence during December and February (aOR: 2.86, 95% CI: 2.43-3.6, p = 0.001). Discussion: This is the first meta-analysis including all the studies on prevalence, molecular epidemiology, and genetic diversity of rotavirus from 1973 to 2023, pre-vaccination period in Bangladesh. This study will provide overall scenario of rotavirus genetic diversity and seasonality during pre-vaccination period and aids in policy making for rotavirus vaccination program in Bangladesh. This work will add valuable knowledge for vaccination against rotavirus and compare the data after starting vaccination in Bangladesh.

Multidrug resistance pattern and molecular epidemiology of pathogens among children with diarrhea in Bangladesh, 2019-2021.

Antimicrobial and multidrug resistance (MDR) pathogens are becoming one of the major health threats among children. Integrated studies on the molecular epidemiology and prevalence of AMR and MDR diarrheal pathogens are lacking. A total of 404 fecal specimens were collected from children with diarrhea in Bangladesh from January 2019 to December 2021. We used conventional bacteriologic and molecular sequence analysis methods. Phenotypic and genotypic resistance were determined by disk diffusion and molecular sequencing methods. Fisher's exact tests with 95% confidence intervals (CIs) was performed. Prevalence of bacterial infection was 63% (251 of 404) among children with diarrhea. E. coli (29%) was the most prevalent. E. coli, Shigella spp., V. cholerae, and Salmonella spp., showed the highest frequency of resistance against ceftriaxone (75-85%), and erythromycin (70-75%%). About 10-20% isolates of E. coli, V. cholerae and Shigella spp. showed MDR against cephem, macrolides, and quinolones. Significant association (p value < 0.05) was found between the phenotypic and genotypic resistance. The risk of diarrhea was the highest among the patients co-infected with E. coli and rotavirus [OR 3.6 (95% CI 1.1-5.4) (p = 0.001)] followed by Shigella spp. and rotavirus [OR 3.5 (95% CI 0.5-5.3) (p = 0.001)]. This study will provide an integrated insight of molecular epidemiology and antimicrobial resistance profiling of bacterial pathogens among children with diarrhea in Bangladesh.

High prevalence of norovirus GII.4 Sydney among children with acute gastroenteritis in Bangladesh, 2018-2021.

BACKGROUND: Active molecular surveillance and rapid diagnosis method to track an outbreak of norovirus in Bangladesh is lacking. This study aims to determine the genotypic diversity, molecular epidemiology and evaluate a rapid diagnosis method. METHODS: A total of 404 fecal specimens were collected from children aged below 60 months from January 2018 to December 2021. All samples were analyzed by reverse transcriptase polymerase chain reaction molecular sequencing of partial VP1 nucleotide. Immunochromatography kit (IC, IP Rota/Noro) was evaluated against reference test method. RESULTS: We found norovirus in 6.7 % (27 of 404) fecal specimens. A wide diversity of norovirus genotype including GII.3, GII.4, GII.5, GII.6, GII.7, and GII.9 were detected. Norovirus strain GII.4 Sydney-2012 was the most predominant (74 %, 20 of 27) followed by GII.7 (7.4 %), GII.9 (7.4 %), GII.3 (3.7 %), GII.5 (3.7 %) and GII.6 (3.7 %), respectively. Co-infection of rotavirus and norovirus (19 [4.7 %] of 404) was the most prevalent. We found higher odds of prolonged health impact [OR 1.93 (95 % CI 0.87-3.12) (p = .001)] among patients with co-infection. The incidence of norovirus was significant among the children below 24 months (p = 0.001). Significant relation of temperature with the cases of norovirus was detected (p = 0.001). The IC kit provided high specificity (99.3 %) and sensitivity (100 %) for the detection of norovirus. CONCLUSIONS: This study will provide an integrated insight on the genotypic diversity and rapid identification method of norovirus in Bangladesh.

Prevalence and impact of long COVID-19 among patients with diabetes and cardiovascular diseases in Bangladesh.

Introduction: Co-prevalence of long-COVID-19, cardiovascular diseases and diabetes is one of the major health challenges of the pandemic worldwide. Studies on long-COVID-19 and associated health outcomes are absent in Bangladesh. The main aim of this study was to determine the prevalence and impact of long-COVID-19 on preexisting diabetes and cardiovascular diseases (CVD) on health outcomes among patients in Bangladesh. Methods: We collected data from 3,250 participants in Bangladesh, retrospectively. Multivariable logistic regression model was used to determine the odds ratio between independent and dependent variables. Kaplan-Meier survival curve was used to determine the cumulative survival. Results: COVID-19 was detected among 73.4% (2,385 of 3,250) participants. Acute long-COVID-19 was detected among 28.4% (678 of 2,385) and chronic long-COVID-19 among 71.6% (1,707 of 2,385) patients. CVD and diabetes were found among 32%, and 24% patients, respectively. Mortality rate was 18% (585 of 3,250) among the participants. Co-prevalence of CVD, diabetes and COVID-19 was involved in majority of fatality (95%). Fever (97%), dry cough (87%) and loss of taste and smell (85%) were the most prevalent symptoms. Patients with co-prevalence of CVD, diabetes and COVID-19 had higher risk of fatality (OR: 3.65, 95% CI, 2.79-4.24). Co-prevalence of CVD, diabetes and chronic long-COVID-19 were detected among 11.9% patients. Discussion: Risk of hospitalization and fatality reduced significantly among the vaccinated. This is one of the early studies on long-COVID-19 in Bangladesh.

Novel human adenovirus strain, Bangladesh.

We report a novel human adenovirus D (HAdV-65) isolated from feces of 4 children in Bangladesh who had acute gastroenteritis. Corresponding genes of HAdV-65 were related to a hexon gene of HAdV-10, penton base genes of HAdV-37 and HAdV-58, and a fiber gene of HAdV-9. This novel virus may be a serious threat to public health.

Genomic surveillance, evolution and global transmission of SARS-CoV-2 during 2019-2022.

In spite of the availability of vaccine, the health burden associated with the COVID-19 pandemic continues to increase. An estimated 5 million people have died with SARS-CoV-2 infection. Analysis of evolution and genomic diversity can provide sufficient information to reduce the health burden of the pandemic. This study focused to conduct worldwide genomic surveillance. About 7.6 million genomic data were analyzed during 2019 to 2022. Multiple sequence alignment was conducted by using maximum likelihood method. Clade GK (52%) was the most predominant followed by GRY (12%), GRA (11%), GR (8%), GH (7%), G (6%), GV (3%), and O (1%), respectively. VOC Delta (66%) was the most prevalent variant followed by VOC Alpha (18%), VOC Omicron (13%), VOC Gamma (2%) and VOC Beta (1%), respectively. The frequency of point mutations including E484K, N501Y, N439K, and L452R at spike protein has increased 10%-92%. Evolutionary rate of the variants was 23.7 substitution per site per year. Substitution mutations E484K and N501Y had significant correlation with cases (r = .45, r = .23), fatalities (r = .15, r = .44) and growth rate R0 (r = .28, r = .54). This study will help to understand the genomic diversity, evolution and the impact of the variants on the outcome of the COVID-19 pandemic.

Development of high temperature simultaneous saccharification and fermentation by thermosensitive Saccharomyces cerevisiae and Bacillus amyloliquefaciens.

Scarcity of energy and pollution are two major challenges that have become a threat to all living things worldwide. Bioethanol is a renewable, ecological-friendly clean energy that may be utilized to address these issues. This study aimed to develop simultaneous saccharification and fermentation (SSF) process through high temperature-substrate adaptation and co-cultivation of S. cerevisiae with other potential amylolytic strains. In this study, we adapted our previously screened thermosensitive Saccharomyces cerevisiae Dj-3 strain up-to 42 °C and also screened three potential thermotolerant amylolytic strains based on their starch utilization capability. We performed SSF fermentation at high temperature by adapted Dj-3 and amylolytic strains using 10.0% starch feedstock. Interestingly, we observed significant ethanol concentration [3.86% (v/v)] from high temperature simultaneous saccharification and fermentation (HSSF) of adapted Bacillus amyloliquefaciens (C-7) and Dj-3. We attribute the significant ethanol concentration from starch of this HSSF process to C-7's high levels of glucoamylase activity (4.01 U/ml/min) after adaptation in starch (up-to 42 °C) as well as Dj-3's strong glucose fermentation capacity and also their ethanol stress tolerance capability. This study suggests the significant feasibility of our HSSF process.

An increasing trend of human sapovirus infection in Japan, 2009 to 2019: An emerging public health concern.

BACKGROUND: Human sapovirus (SaV) is an important etiologic agent of childhood diarrhea. This study aims to investigate the burden of SaV infection in childhood diarrhea in Japan from 2009-2019, to understand the changes in SaV infection after the introduction of rotavirus (RV) vaccination in Japan in 2011. METHODS: Stool samples were collected from children aged ≤ 12 years old with acute gastroenteritis (AGE) who visited outpatient clinics of six prefectures in Japan. The viral RNA was detected by RT-PCR and genogroups and genotypes were determined through sequence-based analysis. RESULTS: Among 5697 stool samples, 318 (5.6%) samples remained SaV-positives showing the highest prevalence in June and 12-24 month aged children. The most predominant genotype was GI.1 (56.8%), followed by GI.2 (19.2%), GII.1 (10.8%), GIV.1 (9.4%), GI.3 (1.7%), GII.2 (1.4%), GII.3 and GII.5 (0.3%). Importantly, an increasing trend (P = 0.016) of SaV infection was observed during this period. In particular, SaV-detection rate was increased significantly (P = 0.033) from 4.3% in pre-rotavirus (RV)-vaccination era to 6.1% in post-RV-vaccination era. We provided evidence that this increase in SaV infection was mainly attributed by coinfections. CONCLUSIONS: The upward trend of SaV infection, particularly after the introduction of RV-vaccination, is an emerging concern. Attention should be paid to control this upward trend of SaV infection to ensure maximum benefits of implementation of RV vaccines towards reducing overall childhood diarrhea worldwide.

Impact of Zinc, Vitamins C and D on Disease Prognosis among Patients with COVID-19 in Bangladesh: A Cross-Sectional Study.

Vitamin C, (ascorbic acid), vitamin D (cholecalciferol) and zinc (zinc sulfate monohydrate) supplements are important in immunity against coronavirus disease-2019 (COVID-19). However, a limited number of studies have been conducted on the association of vitamins and supplements with the reduced risks of COVID-19 infection. This study aims to evaluate the association of vitamins and supplements as treatment options to reduce the severity of COVID-19. Data were collected from 962 participants from 13 December 2020 to 4 February 2021. The presence of COVID-19 was confirmed by qRT-PCR. The Chi-square test and multivariate regression analyses were conducted. The ratio of uptake of vitamin C:vitamin D:zinc was 1:1:0.95. Uptake of vitamin C, vitamin D and zinc were significantly associated with the reduced risk of infection and severity of COVID-19 (OR: 0.006 (95% CI: 0.03-0.11) (p = 0.004)) and (OR: 0.03 (95% CI: 0.01-0.22) (p = 0.005)). The tendency of taking supplements was associated with the presence of infection of COVID-19 (p = 0.001), age (p = 0.02), sex (p = 0.05) and residence (p = 0.04). The duration of supplementation and medication was significantly associated with reduced hospitalization (p = 0.0001). Vitamins C, D and zinc were not significantly (p = 0.9) associated with a reduced risk of severity when taken through the diet. Hospitalization (p = 0.000001) and access to health facilities (p = 0.0097) were significantly associated with the survival period of the participants. Participants with better access to health facilities recovered early (OR: 6.21, 95% CI 1.56-24.7). This study will add knowledge in the field of treatment of COVID-19 by using vitamins and zinc supplements.

Novel recombinant sapovirus in Bangladesh.

BACKGROUND: Recombination of RNA viruses plays an important part in molecular epidemiological study, virus evolution, vaccine design, and viral control programs. Sapovirus, a member of the family Caliciviridae, is one of the major causative agents of viral gastroenteritis affecting all age groups. METHODS: Sapovirus capsid and polymerase regions were amplified by PCR using specific primers. PCR products were sequenced directly and sequence analysis was performed using CLUSTAL X, SimPlot, and MEGA 4 software package. RESULTS: Based on the genetic analysis, a novel, naturally occurring recombinant sapovirus strain was identified in Bangladesh. Breakpoint analysis of the recombinant sapovirus showed that the recombination site was at the open reading frame ORF1/ORF2 overlap. CONCLUSIONS: We described the genetic characterization of a novel, naturally occurring recombinant sapovirus and provided the first evidence of recombination in sapovirus in Bangladesh.

Genetic diversity and emergence of norovirus GII/4-2006b in Japan during 2006-2007.

BACKGROUND: Noroviruses (NoV) are important causes of acute gastroenteritis in infants and young children. This study investigated the prevalence of NoV infections in infants and children with acute gastroenteritis in Japan from July 2006 to June 2007. METHODS: A total of 628 fecal specimens were collected from infants and children with acute gastroenteritis in five different places (Maizuru, Tokyo, Sapporo, Saga and Osaka), Japan during the period of July 2006 to June 2007. All fecal specimens were examined for NoV by reverse transcription-polymerase chain reaction. Molecular analysis of NoV was carried out by sequencing methods. RESULTS: From 628 fecal specimens tested, 15.6% (99 of 628) were positive for NoV. Of these, NoV GII most predominant, with a prevalence of 15.5% (97 of 99). Analysis of nucleotide and amino acid sequences revealed that NoVGII strains comprised GII/4 (89%), GII/3 (6.4%), GII/7 (2.3%), and GII/2 (2.3%) genotypes. Among NoVGII/4 strains, all of them belonged to genotype GII/4 2006b variants. Our results clearly indicated that NoV infections were most commonly observed in winter seasons in Japan. CONCLUSIONS: In conclusion, this study shows the predominance of NoVGII/4 2006b variants and NoV is still burden of disease among Japanese pediatric population.

Efficacy, Immunogenicity and Safety of COVID-19 Vaccines: A Systematic Review and Meta-Analysis.

There is a significant research gap in meta-analysis on the efficacy and safety of coronavirus disease 2019 (COVID-19) vaccines. This study analyzed the efficacy of COVID-19 vaccines. Published phase I, phase II, and phase III trials analyzing safety and immunogenicity and phase III randomized clinical trials evaluating the efficacy of COVID-19 vaccines were included. We searched MEDLINE, Scopus, and The Lancet for published articles evaluating the relative reduction in COVID-19 risk after vaccination. Selected literatures were published between December 15, 2019 and May 15, 2021 on the safety, efficacy, and immunogenicity of COVID-19 vaccines. This meta-analysis included studies that confirmed cases of COVID-19 using reverse transcriptase polymerase chain reaction. This study detected 8,926 eligible research articles published on COVID-19 vaccines. Of these, 25 studies fulfilled the inclusion criteria. Among the selected articles, 19 randomized clinical trials, 2 non-randomized clinical trials, and 3 observational studies were analyzed. Seven (28%) studies were included in the meta-analysis. The efficacy of the adenovirus vector vaccine was 73% (95% CI = 69-77) and that of the messenger RNA (mRNA) vaccine was 85% (95% CI = 82-88) in participants aged ≥18 years. There are no reports of clinical trials in participants aged under 16 years. The production of neutralizing antibodies against receptor-binding domains (RBDs) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in >90% of the vaccinated samples was reported within 0-30 days of the first or the second dose of the vaccine. Pain at the injection site was the most common local symptom in people receiving mRNA vaccines (29%-85% of participants). Fever (0.2%-95%) was the most prevalent in people receiving adenovirus vector vaccines, and fatigue (8.4%-55%) was the most common side effect in people receiving the mRNA vaccines. Studies suggest that mRNA vaccines and adenovirus vector vaccines can provide moderate to high protection against COVID-19 infection in people over 18 years. Evidence of the long-term protection of the vaccines in people aged under 16 years against the multiple variants of COVID-19 are limited. This study will provide an integrated evaluation on the efficacy, safety, and immunogenicity of the COVID-19 vaccines.

Molecular Epidemiology, Evolution and Reemergence of Chikungunya Virus in South Asia.

Chikungunya virus (CHIKV) is a vector (mosquito)-transmitted alphavirus (family Togaviridae). CHIKV can cause fever and febrile illness associated with severe arthralgia and rash. Genotypic and phylogenetic analysis are important to understand the spread of CHIKV during epidemics and the diversity of circulating strains for the prediction of effective control measures. Molecular epidemiologic analysis of CHIKV is necessary to understand the complex interaction of vectors, hosts and environment that influences the genotypic evolution of epidemic strains. In this study, different works published during 1950s to 2020 concerning CHIKV evolution, epidemiology, vectors, phylogeny, and clinical outcomes were analyzed. Outbreaks of CHIKV have been reported from Bangladesh, Bhutan, India, Pakistan, Sri Lanka, Nepal, and Maldives in South Asia during 2007-2020. Three lineages- Asian, East/Central/South African (ECSA), and Indian Ocean Lineage (IOL) are circulating in South Asia. Lineage, ECSA and IOL became predominant over Asian lineage in South Asian countries during 2011-2020 epidemics. Further, the mutant E1-A226V is circulating in abundance with Aedes albopictus in India, Bangladesh, Nepal, and Bhutan. CHIKV is underestimated as clinical symptoms of CHIKV infection merges with the symptoms of dengue fever in South Asia. Failure to inhibit vector mediated transmission and predict epidemics of CHIKV increase the risk of larger global epidemics in future. To understand geographical spread of CHIKV, most of the studies focused on CHIKV outbreak, biology, pathogenesis, infection, transmission, and treatment. This updated study will reveal the collective epidemiology, evolution and phylogenies of CHIKV, supporting the necessity to investigate the circulating strains and vectors in South Asia.