Disruption of seasonal influenza circulation and evolution during the 2009 H1N1 and COVID-19 pandemics in Southeastern Asia

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 8, 2025

East, South, and Southeast Asia (together referred to as Southeastern hereafter) have been recognized critical areas fuelling the global circulation of seasonal influenza. However, influenza migration network within remains unclear, including how pandemic-related disruptions altered this network. We leveraged genetic, epidemiological, airline travel data between 2007-2023 characterise dispersal patterns A/H3N2 B/Victoria viruses both out Asia, during perturbations by 2009 A/H1N1 COVID-19 pandemics. During pandemic, consistent autumn-winter movement waves from temperate regions were interrupted for subtype/lineages, however pandemic only disrupted spread. find a higher persistence than in identify distinct antigenic evolution two pandemics, compared interpandemic levels; similar are observed using genetic distance. The internal structure markedly diverged season, lesser extent, season. Our findings provide insights into heterogeneous impact on circulation, which can help anticipate effects future pandemics potential mitigation strategies dynamics. key dissemination viruses, but major (e.g., pandemics) may disrupt their role. Here, authors demonstrate H1N1 Asia.

Language: Английский

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Sequence analysis of respiratory syncytial virus cases reveals a novel subgroup -B strain circulating in north-central Italy after pandemic restrictions

Journal of Clinical Virology, Journal Year: 2024, Volume and Issue: 173, P. 105681 - 105681

Published: May 10, 2024

Following the pandemic restrictions, epidemiology of respiratory syncytial virus (RSV) has changed, leading to intense hospitalization peaks. This study, conducted at multiple sites in Italy, aimed describe temporal dynamics two post-COVID-19 RSV epidemics. Additionally, circulating RSV-A and -B lineages were characterized compared those found 2018 2019. Respiratory specimens data collected from RSV-positive patients, both inpatients, outpatients, all ages three north-central Italy. To analyze these samples, roughly one-sixth sequenced attachment glycoprotein G gene subjected phylogenetic mutational analyses, including pre-pandemic sequences The first post-pandemic surge cases was quite intense, occurring October 2021 early January 2022. subsequent epidemic (from November 2022 March 2023) also had a high impact, by rise elderly patient cases. Post-pandemic caused various strains present Italy prior COVID-19. In contrast, distinct RSV-B lineage, which concurrently spreading other countries, identified as main cause 2022–2023 but remained undetected before pandemic. study describes subgroups uncovers lineage with genetic divergence that may have increased impact decreased population immunity.

Language: Английский

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Analysis of the incidence of influenza before and after the COVID‐19 pandemic in South Korea

Tropical Medicine & International Health, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 6, 2024

Abstract Objectives Influenza outbreaks of varying size occur every year, but during the COVID‐19 pandemic, many countries experienced influenza at lower levels. However, following relaxation prevention measures in 2022, incidence began to increase gradually. Thus, this study compared occurrence from week 36 2017, before outbreak, until 2023. Methods The analysis was conducted using influenza‐like illness data available Korea Disease Control and Prevention Agency infectious disease website. Additionally, examine changes 20 January 2020 31 August 2023 were obtained KDCA Coronavirus 19 homepage. Results During which corresponds 2020/2021 2021/2022 seasons, there no seasonal epidemic, rates below usual outbreak 2022/2023 season, when spread had eased, a pattern similar that observed pandemic noted. Furthermore, correlation between showed significant entire period. emerged ( r = 0.393, p <0.05). These results suggest suppressed returned typical patterns after policies eased. Conclusion positive incidences indicates COVID‐19, longer novel pandemic‐causing disease, may have transitioned an endemic influenza.

Language: Английский

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Epidemiology and Genetic Evolutionary Analysis of Influenza Virus Among Children in Hainan Island, China, 2021–2023

Pathogens, Journal Year: 2025, Volume and Issue: 14(2), P. 142 - 142

Published: Feb. 3, 2025

Background: During the COVID-19 pandemic, we continuously monitored epidemiology of influenza virus among pediatric patients from January 2021 to December 2023 in Hainan Island, China. Methods: In this study, collected 54,974 nasopharyngeal swab samples for A Virus (IAV) testing and 53,151 B (IBV) outpatients. Additionally, also 19,687 inpatients IAV IBV testing. Outpatient were screened viruses (IVs) infection by colloidal gold method. Targeted Next-Generation Sequencing (tNGS) was used detect infections inpatients. Influenza types identified analyzing HA/NA partial regions. Results: The findings revealed a significant decrease rate over specified period, while exhibited rising trend. B/Victoria lineage dominant epidemic strain 2021, strains 2022 underwent dynamic transformation A/H3N2 A/H1N1. Phylogenetic analysis close relationships circulating strains. Nonetheless, because sample size is limited, additional research required. Conclusions: Our suggest that predominant population are undergoing changes, influenced implementation relaxation non-pharmaceutical intervention measures. These highlight need adaptive vaccination containment strategies, particularly tropical regions like Hainan, where climate public health policies significantly impact viral transmission patterns. insights gained study could inform more effective strategies similar mitigate outbreaks future.

Language: Английский

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Shifts in Respiratory Virus Epidemiology on Reunion Island From 2017 to 2023: Impact of COVID‐19 Pandemic and Non‐Pharmaceutical Interventions

Influenza and Other Respiratory Viruses, Journal Year: 2025, Volume and Issue: 19(3)

Published: March 1, 2025

ABSTRACT Background The COVID‐19 pandemic has reshaped the landscape of respiratory viral infections globally. This study examines these changes on Reunion Island, a French department in southeastern Indian Ocean. Methods Retrospective data from 2017 to 2023, over 24,000 samples collected across hospital system, partner laboratories, and network sentinel physicians, were analyzed correlated with number consultations at emergency physicians for symptoms acute (ARIs). epidemiology viruses was by comparing pre‐ post‐COVID‐19 periods assess disruptions seasonal patterns, virus prevalence, affected age groups. Results Our database effectively captured island, as demonstrated its strong correlation ARI. Post‐COVID‐19, influenza exhibited multiple epidemic waves within single year, deviating traditional annual peak showing significant decline circulation 2020 2023. syncytial also impacted post‐COVID‐19, epidemics starting earlier lasting longer compared pre‐COVID‐19 years. Human rhinovirus circulated more prominently post‐COVID period, accounting up one‐third positive cases, becoming most prevalent (excluding SARS‐CoV‐2). Conclusions These findings suggest notable impact associated NPIs Island since mid‐2020. They underscore complex interplay between interference, public health interventions, behavioral changes, youth immunity, emphasizing need adaptable strategies managing outbreaks era.

Language: Английский

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Retrospective Epidemiological Analysis of Influenza A Infections in a Single Hospital in Korea (2007–2024): Age, Sex, and Seasonal Patterns

Pathogens, Journal Year: 2025, Volume and Issue: 14(3), P. 282 - 282

Published: March 14, 2025

Influenza A is a respiratory virus that causes high infection rates and mortality worldwide, particularly affecting high-risk groups such as children, older adults, individuals with chronic conditions. This retrospective study was conducted at single tertiary hospital in Korea to analyze the epidemiological characteristics of influenza infections from 2007 2024, focusing on age, sex, seasonal variations. Using multiplex real-time PCR data 23,284 individuals, we found overall positivity rate for 5.6%, fluctuations showing highest winter (14.0%) lowest summer (0.5%). Age-based analysis revealed significantly higher adults (7.9%) (7.6%) than children (5.0%) infants (3.1%). No significant differences were observed between sexes (male: 5.43%, female: 5.76%, p = 0.428). These findings provide essential insights into regional patterns A, emphasizing importance targeted vaccination strategies, adaptive public health interventions, continuous surveillance effective prevention outbreak control management.

Language: Английский

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Emergency response to the COVID-19 pandemic and beyond: Qualitative content analysis

F1000Research, Journal Year: 2025, Volume and Issue: 14, P. 295 - 295

Published: March 14, 2025

The Earth continues to suffer from the impact of coronavirus disease 2019 (COVID-19) outbreak even now, particularly due absence appropriate theoretical frameworks for related emergency responses. In this study, we provided a simplified model response infection. We employed qualitative content analysis, using Preferred Reporting Items Systematic Reviews and Meta-Analyses (PRISMA) 2020 checklist flow diagram. Specifically, examined eight underlying factors (leaders’ inability, focus on economic recovery, controversies regarding usage face masks, unprecedented reliance herd immunity, hasty research development, late decision-making, coordination failure, occurrence natural hazards) selected overarching (global leadership, national policies, individual strategies, culture, timing, communication, contingency). Considering these factors, proposed “Earth as comprehensive system” approach, under which elements pandemic are comprehensively included facilitate problem-solving, social support, strategic use, assistance various professionals, education. The operational mechanism approach clearly emphasizes unified efforts responding by systematically including interdependent components Earth.

Language: Английский

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Excess Respiratory Hospitalisations Associated with Influenza, Respiratory Syncytial Virus and SARS‐CoV‐2 in Singapore from 2015 to 2023

Influenza and Other Respiratory Viruses, Journal Year: 2025, Volume and Issue: 19(4)

Published: April 1, 2025

ABSTRACT Background The patterns of circulation and burden influenza respiratory syncytial virus (RSV) in Singapore are affected by the COVID‐19 pandemic containment measures. These relation to SARS‐CoV‐2 a post‐pandemic era unclear. Methods Using data from 2015 2023, we estimated excess influenza‐, RSV‐ SARS‐CoV‐2‐associated hospitalisation Singapore, adjusted for rhinovirus/enterovirus activity generalised additive models. include pneumonia (P&I) national inpatient database community‐wide acute infection (ARI) sentinel surveillance programme, stratified age groups. Results Across all groups, proportion associated with influenza, RSV was 13.2% (95% CI 5.0%–21.6%), 19.3% 13.8%–25.0%) 4.0% 0.9%–12.1%) respectively. From 2019 all‐age influenza‐associated declined 264.4 per 100,000 person‐years 214.2–313.2) 203.7 76.8–333.6). In contrast, RSV‐associated after 62.2 13.8–186.9), similar pre‐pandemic observations. Peak seasonal occurred 3–8 weeks later as compared time peak activity. Conclusion overall has its is comparable SARS‐CoV‐2. Furthermore, shifts timing suggest potential need review vaccine recommendations Singapore.

Language: Английский

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Surveillance of influenza viruses circulating from 2017/2018 to 2023/2024 seasons in Veneto Region, North-East Italy

Virology Journal, Journal Year: 2025, Volume and Issue: 22(1)

Published: April 24, 2025

Language: Английский

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Quantified impacts of non‐pharmaceutical interventions on influenza circulation during the COVID‐19 pandemic in 13 African countries, 2020–2022

Influenza and Other Respiratory Viruses, Journal Year: 2024, Volume and Issue: 18(1)

Published: Jan. 1, 2024

Abstract Nonpharmaceutical interventions (NPIs) for SARS‐CoV‐2 disrupted circulation of influenza. We used data from 13 African countries and generalized linear models to identify associations between levels NPIs, using the Oxford Stringency Index, seasonal influenza activity, parameters derived 2020–2022 surveillance. found that each step increase in school closings, average percentage respiratory specimens testing positive across season dropped by 20% (95% CI: 1–38%); no other NPI was significant. These findings may inform slow pandemics possibly during epidemics.

Language: Английский

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