The impact of coronavirus disease 2019 pandemic on bronchiolitis (lower respiratory tract infection) due to respiratory syncytial virus: A systematic review and meta-analysis.

The coronavirus disease 2019 (COVID-19) pandemic has changed the epidemiology of respiratory syncytial virus (RSV) infection which accounts for most bronchiolitis and viral pneumonias in infants. This systematic review and meta-analysis aimed to quantitatively assess the effect of the COVID-19 pandemic on RSV-associated bronchiolitis among hospitalized infants. The study protocol was registered in the PROSPERO database (CRD42022314000) and was designed based on Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines updated in May 2020. The meta-analysis component was modified appropriately to synthesize the pooled proportion of infants having RSV-associated bronchiolitis before the COVID-19 pandemic in 2019 and during the pandemic with 95% confidence interval (CI). We identified and screened 189 articles and systematically reviewed 50 full texts. Eight qualified studies from Europe and China, including 109,186 symptomatic cases of bronchiolitis before the pandemic in 2019 and 61,982 cases in 2020-2021 were pooled by random-effects meta-analysis. The quantitative analysis included laboratory-confirmed RSV infection in 7691 infants with bronchiolitis reported before the pandemic in 2019. Meanwhile, during the pandemic, 4964 bronchiolitis cases were associated with RSV infection. The pooled proportion of RSV-associated bronchiolitis cases before the pandemic in 2019 was 16.74% (95% CI 11.73, 22.43%, 95% prediction interval 0.032, 34.16). The pooled proportion of confirmed RSV cases during the pandemic in 2020/2021 was 19.20% (95% CI 12.01, 27.59%, 95% prediction interval 0.046, 42.35). There was an increase in RSV activity after the relaxation of stringent public health measures during the COVID-19 pandemic.

The impact of COVID-19 pandemic on influenza surveillance: A systematic review and meta-analysis.

Background: Influenza activity was reported to be below the seasonal levels during the Coronavirus disease-2019 (COVID-19) pandemic globally. However, during the severe acute respiratory syndrome corona virus-2 outbreak, the routine real-time surveillance of influenza-like illness and acute respiratory infection was adversely affected due to the changes in priorities, economic constraints, repurposing of hospitals for COVID care, and closure of outpatient services. Methods: A systematic review and meta-analysis were carried out to assess the pooled proportion of symptomatic cases tested for influenza virus before the current pandemic in 2019 and during the pandemic in 2020/21. An electronic search of PubMed/MEDLINE, Scopus, and Google Scholar was carried out for the articles reporting the impact of the COVID-19 pandemic on influenza surveillance among humans using search terms. The study was designed based on Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and the meta-analysis was performed to synthesize the pooled proportion of patients sampled for influenza with 95% confidence interval (CI). Results: The nine qualified studies from the WHO European region, Canada, Japan, Germany, Italy, Spain, South Africa, and the United States were pooled by random-effects meta-analysis. The overall pooled proportion of symptomatic cases sampled for influenza surveillance before and during the pandemic was 2.38% (95% CI 2.08%-2.67%) and 4.18% (95% CI 3.8%-4.52%), respectively. However, the pooled proportion of samples tested for influenza before the pandemic was 0.69% (95% CI 0.45%-0.92%) and during the pandemic was 0.48% (95% CI 0.28%-0.68%) when studies from Canada were excluded. Conclusion: The meta-analysis concludes that globally there was a decline in influenza surveillance during the COVID-19 pandemic except in Canada.

Currently circulating genotypes of Hepatitis A virus in South West, East and North East India, 2017-2018.

Background: This study was carried out to understand the circulating genotypes of Hepatitis A virus (HAV) in South West, East and North East India during the period 2017-2018 as a part of acute febrile illness surveillance at the Manipal Institute of Virology. Methods: Archived serum samples of 48 Hepatitis A confirmed cases were subjected to RNA extraction using QIAamp® Viral RNA Mini Kit (QIAGEN, Germany). The samples with molecular confirmation for HAV by reverse transcriptase real-Time PCR (Real Star® HAV RT-PCR Kit 2.0, Altona Diagnostics, GmbH, Hamburg, Germany) were further subjected to nested conventional PCR targeting the 5' UTR region. The purified PCR products were sequenced using Big Dye Terminator Kit (Applied Biosystems, USA), in a 3500 XL genetic analyzer (Applied Biosystems, USA). The edited sequences by means of MEGA X (MEGA version 10.1) were compared with reference sequences in the NCBI nucleotide database. Results: From states of Assam, Goa, Gujarat, Karnataka, Kerala, Maharashtra, Odisha, Tamil Nadu and Tripura, 139 Hepatitis A and 33 Hepatitis E cases were reported during the study period. The median age of the acute Hepatitis A cases was 19 years (IQR 12.8-24) and most of the affected individuals were students between 10 and 19 years (52.5%). In the present study, 14 samples from Assam, Goa, Gujarat, Karnataka, Odisha, Kerala, Maharashtra and Tamil Nadu were genotyped as genotype IIIA by nested conventional polymerase chain reaction. Conclusion: The circulating HAV genotype in South West, North East and East India between 2017 and 2018 was IIIA.

Adaptive Immune Responses in Humans During Nipah Virus Acute and Convalescent Phases of Infection.

BACKGROUND: Nipah virus (NiV) is 1 of 10 potential causes of imminent public health emergencies of international concern. We investigated the NiV outbreak that occurred in May 2018 in Kerala, India. Here we describe the longitudinal characteristics of cell-mediated and humoral immune responses to NiV infection during the acute and convalescent phases in 2 human survivors. METHODS: Serial blood samples were obtained from the only 2 survivors of the NiV outbreak in Kerala. We used flow cytometry to determine the absolute T-lymphocyte and B-lymphocyte counts and the phenotypes of both T and B cells. We also detected and quantitated the humoral immune response to NiV by virus-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) enzyme-linked immunosorbent assay. RESULTS: Absolute numbers of T lymphocytes remained within normal limits throughout the period of illness studied in both survivors. However, a marked elevation of activated CD8 T cells was observed in both cases. More than 30% of total CD8 T cells expressed Ki67, indicating active proliferation. Proliferating (Ki-67+) CD8 T cells expressed high levels of granzyme B and PD-1, consistent with the profile of acute effector cells. Total B-lymphocyte, activated B-cell, and plasmablast counts were also elevated in NiV survivors. These individuals developed detectable NiV-specific IgM and IgG antibodies within a week of disease onset. Clearance of NiV RNA from blood preceded the appearance of virus-specific IgG and coincided with the peak of activated CD8 T cells. CONCLUSIONS: We describe for the first time longitudinal kinetic data on the activation status of human B- and T-cell populations during acute NiV infection. While marked CD8 T-cell activation was observed with effector characteristics, activated CD4 T cells were less prominent.

Genetic analysis of Enterovirus D68 associated with pneumonia in children from South India.

EV-D68 is an emerging enterovirus infection associated with severe acute respiratory illness (SARI), acute flaccid myelitis (AFM) and acute flaccid paralysis (AFP). While EV-D68 outbreaks and sporadic cases are reported globally, a single case has been reported from India. The present study aims to investigate the molecular epidemiology and clinical characteristics of EV-D68-associated SARI cases from South India. We screened influenza-negative archived throat swab specimens from Influenza-Like Illness (ILI) and SARI cases (n=959; 2016 to 2018 period) for enteroviruses by pan-enterovirus real-time RT-PCR. Thirteen samples positive for enteroviruses were typed by PCR and sequencing based on VPI, VP2 and/or 5'NCR regions. One EV-D68 RNA sample was subjected to next-generation sequencing for whole genome characterisation. Among 13 enterovirus cases, four were ECHO-11, three EV-D68, two CV-A16 and one each EV-71, CV-B1, CV-B2 and CV-A9. All three cases of EV-D68 infection were reported in children below 2 years of age from Kerala state of South India during June and July 2017. The patients developed pneumonia without any neurological complications. Sequencing based on VPI and 5'NCR regions showed that EV-D68 strains belong to the novel subclade B3. The EV-D68 complete genome identified with two unique amino acid substitutions in VP1 (T-246-I) and 3D (K-344-R) regions. This study reiterates the EV-D68 novel subclade B3 circulation in India and indicates the urgent need for structured EV-D68 surveillance in the country to describe the epidemiology.

The prevalence of anti-hepatitis C antibody among acute febrile illness cases in Idar Taluk, Gujarat, West India.

Purpose: The major cause of chronic hepatitis is infections with hepatitis B virus and hepatitis C virus (HCV) globally. However, there exists sparse epidemiological data regarding the prevalence of HCV infection from India. Methodology: We carried out a cross-sectional study to estimate the prevalence of anti-HCV antibody among acute febrile illness cases aged between 1 and 65 years in Idar Taluk, Sabarkantha district, Gujarat state located in West India. A total of 702 serum samples collected from the study area during the year 2017, were screened for anti-hepatitis C IgG by enzyme-linked immunosorbent assay. The serum samples screened positive were then subjected to molecular testing for confirmation. Results: Among the 702 study participants screened, 16 cases were reported to be anti-HCV IgG positive with an estimated seroprevalence rate of 2.3% (95% confidence interval: 1.4%-3.7%). Out of the 16 cases, two samples were confirmed positive by molecular testing indicating active infection. When analysed phylogenetically, one strain was genotyped as HCV1b genotype, and the other one was clustered along with HCV3a genotype. Both the patients with hepatitis C infection were observed to be having a probable 1-year survival rate of 100% and a 2-year survival rate of 85% when the Child-Turcotte-Pugh classification was applied. Conclusion: The estimated seroprevalence of hepatitis C in Idar Taluk, Sabarkantha district, west India was 2.3%. HCV genotypes 1b and 3a were observed to be circulating in the study area.

Currently circulating genotypes of hepatitis E virus in India, 2014-2018.

Purpose: Hepatitis E virus (HEV) is an emerging pathogen causing acute viral hepatitis worldwide. Clinical manifestations often occur in young adults with an increased mortality rate among pregnant women. HEV genotypes 1 and 4 are mainly reported among humans and swines, respectively. Aims: The aim was to study the currently circulating genotypes of HEV in India. Materials and Methods: A retrospective cross-sectional study was carried out at Manipal Institute of Virology to know the circulating genotypes of hepatitis E, spanning over 5 years from August 2014 to September 2018. The serum samples screened serologically positive and confirmed positive for active infection by real-time reverse transcriptase-polymerase chain reaction (PCR) (Real Star® HEV RT-PCR Kit 2.0, Altona Diagnostics, GmbH, Hamburg, Germany) were further subjected to nested conventional PCR targeting the RdRp gene of non-structural ORF1 region. The purified PCR product was sequenced in BigDye Terminator v3.1 Cycle Sequencing Kit (Life Technologies, Thermo Fisher Scientific, USA). The chromatograms obtained by sequencing were analysed using Sequencher 5.4.6, and HEV FASTA sequences were compared with reference sequences for HEV in GenBank Nucleotide Blast. Results: During the study period, there were 317 cases of laboratory-confirmed cases of acute viral hepatitis comprising 202, 70, 43 and 2 cases of hepatitis A, E, B and C, respectively. Serum samples of 70 acute hepatitis cases were positive for anti-hepatitis E IgM. According to the clinical case classification, there were 66 cases of acute viral hepatitis and four cases of fulminant hepatic liver failure. The mean age of the patients was 30.3 years (standard deviation = 12.5). The samples from various parts of India were genotyped as 1a. Conclusion: The HEV genotypes 1a was observed to be the currently circulating strain in the regions studied.