Non-pharmaceutical Interventions Research Articles

Respiratory pathogen spectrum and epidemiological trends in Hainan Province: a retrospective analysis from 2017 to 2023

BackgroundRespiratory tract infections (RTIs) pose a significant global health burden, caused by various pathogens. The COVID-19 pandemic and non-pharmaceutical interventions (NPIs) have created unprecedented challenges for public health systems, inadvertently altering the dynamics of other respiratory pathogens. This study aims to illustrate changes in the pathogen spectrum among RTI patients in Hainan Province before and during the pandemic.MethodsA retrospective study was conducted to demonstrated the epidemiology characteristics of respiratory pathogens across pre-COVID-19, NPI and COVID-19 pandemic in Hainan from 2017 to 2023. A total of 21,036 patients with RTI of all age groups were enrolled and tested for nine common pathogens: influenza A virus (Flu-A), influenza B virus (Flu-B), parainfluenza virus (PIV), Adenovirus (AAV), respiratory syncytial virus (RSV), Q fever Rickettsiae (Q Fever), Legionella pneumophila (L. pne), Chlamydia pneumoniae (C. pne), and Mycoplasma pneumoniae (M. pne).ResultsDuring 2017–2023, the number of RTI patients and pathogen detection rate was gradually decrease from 33.30% (3,886/11,670; pre-COVID-19), to 30.81% (2,034/6,602; NPI) and 22.43% (620/2,764; COVID-19). M. pne (25.52%), Flu-B (3.9%), and PIV (3.12%) were identified as the most prevalent pathogens across three periods. However, the infection rate for M. pne was significantly decrease, and the infection rate for Flu-B and Flu-A were a notable increased in NPI and COVID-19 pandemic. Children aged 0–5 years account for the largest proportion of all RTI patients with the highest infection rate, especially in NPI and COVID-19 pandemic. Flu-A, Flu-B, and RSV exhibited spring-specific seasonal prevalence during NPI and COVID-19 pandemic. Co-infection pattern analysis showed that “M. pne-dominant viruses” co-infection type was prevalent across all three time periods.ConclusionM. pne, Flu-B, Flu-A, and PIV were found to be the main causative pathogens of RTI patients in Hainan Province, and their prevalence levels and seasonal patterns had changed during large-scale NPI and COVID-19 pandemic.

Assessing the Impact of Non‐Pharmaceutical Interventions on COVID‐19 in India: A Combined CCE and Quantile Regression Approach

ABSTRACTThis paper presents supposedly the first empirical evidence on the impact of non‐pharmaceutical interventions (NPIs) on deaths and infections due to COVID‐19 in India. I use the Oxford COVID‐19 Government Response Tracker (OxCGRT) database of daily government responses of stringency, containment, economic support, and overall government response from Jan 28, 2020, till December 31, 2022. I use CS‐ARDL to quantify the short‐ and long‐term associations and quantile regression to uncover the impact of NPIs across heterogeneous quantiles. The overall government support, which aggregates all three NPIs, demonstrates a significant adverse effect on fatalities. In the long‐term, a 10% increase in it reduces deaths by 1.94% and infections by 10.67%. Stringency and containment interventions are equally found to be effective. Economic support is significantly associated with a reduction in death rates—by 1.89% in the short term and 1.07% in the long term—and a 10.28% reduction in infection rates over the long term. In the short term, NPIs are not notably effective in reducing infections; however, their effectiveness improves over the long term. Quantile regression reveals a heterogeneous impact of NPIs on COVID‐19 outcomes across the distribution. NPIs show limited effectiveness at lower quantiles, but their impact becomes increasingly significant at higher quantiles, particularly for infections, where the effect size is notably larger. Results suggest bi‐directional causality, as higher cases lead to stricter interventions, subsequently lowering incidence rates. I establish that effective pandemic management requires a phased approach to NPIs, with region‐specific flexibility and timely economic support to enhance short‐ and long‐term outcomes. Evidence from India shows that NPIs are indispensable, especially when pharmaceutical options are limited, as they effectively control mortality and support public health resilience.

Did the resurgence of childhood lower respiratory infections offset the initial benefit of COVID-19-related non-pharmaceutical interventions in children? A time-series analysis

BackgroundFollowing non-pharmaceutical interventions (NPI) lifting in 2021, an important surge in childhood lower respiratory tract infections (LRTI) was reported in several countries, raising major concerns about the middle-term consequences of such interventions. Whether this recent upsurge overwhelms the initial benefit of NPI remains unknown.MethodsWe conducted an interrupted time-series analysis based on exhaustive national surveillance systems. All hospitalisations from January 2015 to March 2023 and all ambulatory visits for LRTI from a network of 110 paediatricians from June 2017 to March 2023 were included. The main outcome was the monthly incidence of children hospitalised for LRTI per 100,000 over time, assessed by a seasonally adjusted quasi-Poisson regression model.ResultsWe included 845,047 hospitalisations. The incidence of hospitalisation for LRTI significantly decreased during the NPI period (− 61.7%, 95% CI − 98.4 to − 24.9) and rebounded following NPI lifting, exceeding the pre-NPI baseline trend (+ 12.8%, 95% CI 6.7 to 19.0). We observed similar trends for hospitalisation due to bronchiolitis, pneumonia and pneumonia with pleural effusion, along with ambulatory LRTI. Overall, despite the recent rebound, 31,777 (95% CI, 25,375 to 38,179) hospitalisations for paediatric LRTI were averted since NPI implementation up to 2023.ConclusionsThree years after their implementation, despite an increase in LRTI incidence, the middle-term impact of NPI remains highly beneficial in preventing overall paediatric LRTI. The implementation of some societally acceptable NPI, particularly during epidemics, may be considered in the future to further reduce the burden of paediatric LRTI.

Changes in Seasonal Patterns for Common Pediatric Respiratory Viruses During the COVID Pandemic.

Observed alterations in seasonal patterns of common pediatric respiratory viruses during and immediately after the COVID-19 pandemic had far-reaching implications for the care of ill children. Here, we quantify the effects of the pandemic and related nonpharmaceutical interventions on the prevalence and seasonality of common pediatric respiratory illnesses. We performed a retrospective chart review within a large health network to identify incidence rates of common respiratory viruses and compared them to historical trends. Time series analyses using seasonal autoregressive integrated moving average models were utilized to identify seasonal patterns for the different virus types and quantify deviations from expected incidence rates. Overall, we noted a steep decline in non-COVID viral infection rates at the onset of the COVID pandemic in March 2020, largely coincident with the institution of mask mandates and lockdown measures. This trend continued until the Spring of 2021, at which time non-COVID infections resurged to rates higher than pre-COVID levels. In addition, the historically observed seasonality of these viruses was significantly disrupted by the pandemic. In particular, the historical peaks for influenza A and human metapneumovirus shifted from February and March, respectively, to bimodal peaks in December 2021 and May 2022; respiratory syncytial virus demonstrated an unprecedented Spring/Summer season in 2021; parainfluenza type 1 was unusually active in 2022, an even-numbered year; and influenza B virtually disappeared during and immediately after the pandemic. Our observations add to the growing body of literature supporting the hypothesis that human interactions are one of the key drivers of pediatric respiratory viral seasonality in addition to climate. Understanding the effect of human interactions on disease spread is crucial for the development of effective mitigation measures for future pandemics while avoiding dangerous spikes of other illnesses once those interventions are lifted.

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

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

From mere 'stability' to 'durability'-Revisiting intention dynamics from a self-regulatory perspective with intensive longitudinal methods.

Behavioral intentions predict behavior better if they are stable over time. A statistical argument suggests that this is due to less measurement error, but recent theoretical advances suggest self-regulatory effects: durable intentions remain temporally stable due to their persistence when faced with challenges. Here, we leverage intensive longitudinal data on adherence with non-pharmaceutical interventions (NPIs) during the COVID-19 pandemic (N = 623; total assessments = 19,740; study duration: 6months each). We operationalize intention durability as temporal order-dependent variability (reversed root mean square of successive differences [RMSSD] between each valid assessment). We then examine the within- and between-person moderating effects of intention durability on the intention-behavior association as well as the effects of past on current behavior. In line with the theoretical assumptions, we find that more durable intentions are not only associated with a stronger intention-behavior link on a within- and a between-person level but also a stronger effect of past on current adherence with NPIs. Our findings support the hypothesized moderating effects of intention durability and provide a more nuanced understanding of the self-regulatory processes underlying the temporal stability of intentions.

Global analysis of influenza epidemic characteristics in the first two seasons after lifting the nonpharmaceutical interventions for COVID-19.

The COVID-19 pandemic significantly disrupted the global influenza seasonal patterns due to nonpharmaceutical interventions. This study aims to describe the influenza seasonal characteristics in the first two seasons after lifting COVID-19 NPIs and assess shifts before, during, and after the pandemic. We analyzed country-specific weekly influenza data (2011-2024) from WHO FluNet and collected COVID-19 NPI timing from official announcements. The study was divided into pre-pandemic, pandemic, and post-pandemic phases, estimating epidemic onset, peak week, peak intensity, and duration by climate zones. In temperate countries, peak intensity after the pandemic decreased by 8.4 %, while duration increased by 1.8 weeks, and onset and peak were delayed by 18.5 and 22.8 weeks compared to regular seasonal pattern before the pandemic. Subtropical countries experienced a 17.2 % decrease in peak intensity, a 2.4-week decrease in duration, and delays in onset and peak by 13.5 and 2.3 weeks. Tropical countries had a 10 % decrease in peak intensity, a 3-week reduction in duration, and a 6.6-week delay in onset with no significant change in peak time. Influenza seasonality shifted significantly after the pandemic, with epidemic durations returning to typical patterns but peak intensities remained low. Robust surveillance after an infectious disease pandemic is crucial to inform prevention and control strategies.

Emergence and spread of the SARS-CoV-2 omicron (BA.1) variant across Africa: an observational study.

In mid-November, 2021, the SARS-CoV-2 omicron variant (B.1.1.529; BA.1 sublineage) was detected in southern Africa, prompting international travel restrictions. We aimed to investigate the spread of omicron BA.1 in Africa. In this observational study, samples from patients infected with SARS-CoV-2 from 27 laboratories in 24 African countries, collected between June 1, 2021 and April 14, 2022, were tested for omicron BA.1 and delta (B.1.617.2) variants using real-time RT-PCR. Samples that tested positive for BA.1 by RT-PCR and were collected before estimated BA.1 emergence according to epidemiological properties were excluded from downstream analyses. The diagnostic precision of the assays was evaluated by high-throughput sequencing of samples from four countries. The observed spread of BA.1 was compared with mobility-based mathematical simulations and entries for SARS-CoV-2 in the Global Initiative on Sharing All Influenza Data (GISAID) genomic database. We estimated the effective reproduction number (Rt) at the country level considering the BA.1 fraction and the reported numbers of infections. Phylogeographical analyses were done in a Bayesian framework. Through testing of 13 294 samples from patients infected with SARS-CoV-2, we established that, by November-December, 2021, omicron BA.1 had replaced the delta variant of SARS-CoV-2 in all African subregions, following a south-north gradient, with a median Rt of 2·60 (95% CI 2·46-2·71). This south-north spread, established on the basis of PCR data, was substantiated by phylogeographical reconstructions, ancestral state reconstructions, and GISAID data. PCR-based reconstructions of country-level BA.1 predominance and the availability of BA.1 genomic sequences in GISAID correlated significantly in time (p=0·0002, r=0·78). The first detections of BA.1 in high-income settings beyond Africa were predicted accurately in time by mobility-based mathematical simulations (p<0·0001). Comparing PCR-based reconstructions with mobility-based mathematical simulations suggested that SARS-CoV-2 infections in Africa were under-reported by approximately ten times. Inbound travellers infected with BA.1, departing from five continents, were identified in six African countries by early December, 2021. Omicron BA.1 was widespread in Africa when travel bans were implemented, limiting their effectiveness. Combined with genomic surveillance and mobility-based mathematical modelling, PCR-based strategies can inform Rt and the geographical spread of emerging pathogens in a cost-effective and timely manner, and can guide evidence-based, non-pharmaceutical interventions such as travel restrictions or physical distancing. Bill & Melinda Gates Foundation. For the French, Portugese and Spanish translations of the abstract see Supplementary Materials section.

The impact of community-based, non-pharmaceutical interventions on anxiety and depression in fibromyalgia: A systematic review and network meta-analysis.

Fibromyalgia syndrome (FMS) is often accompanied by anxiety and depression, seriously affecting the prognosis of patients. Active non-pharmacological therapies are the mainstay of treatment, but the optimal choice is still contentious. We did a network meta-analysis(NMA) of RCTs and compared 7 community-based non-pharmacological interventions based on 29 studies. We searched Embase, MEDLINE, PubMed, Scopus, Google Scholar, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) from the database inception to March 2022. The NMA demonstrated that five out of six (83.34%) non-pharmacological interventions were associated with significant improvement in anxiety compared with usual care, with a standardized mean difference (SMD) ranging from -1.14 (95% CI: -1.76 to -0.51) for aquatic exercise to -0.39 (95% CI: 073-0.05) for meditation; six of the seven non-pharmacological interventions (85.71%) were associated with significant improvement in depression, with SMD ranged from -1.18 (95% CI: -1.68 to -0.68) for aquatic exercise to -0.46 (95% CI: -0.86 to -0.05) for education therapy. First of all, there were scale translation biases in this study caused by the different languages of the original study. In addition, there was a lack of direct comparison between the aquatic exercise group and the routine care group, and the third included intervention measures lacked unified implementation standards. Aquatic exercise exhibited distinct advantages compared with other community-based non-pharmacological interventions and is likely to have optimal efficacy in improving anxiety and depression. The study protocol is registered with the Prospective Register of Systematic Reviews (PROSPERO, CRD 42022338406).

Impact of COVID-19 on testing, positive cases, patient characteristics, and hospital contacts for respiratory syncytial virus, influenza, and pneumococcus in Danish children.

Respiratory infections substantially impact pediatric health. The COVID-19 pandemic introduced widespread non-pharmaceutical interventions, which influenced the incidence of common respiratory infections. This comprehensive study investigates the impact of these interventions on the incidence of respiratory syncytial virus, influenza, and invasive pneumococcal disease in Danish children. We conducted a descriptive study based on a cohort of 1,790,464 Danish children from 2012 to 2022. We analyzed data from microbiology tests and hospital contacts to assess infection rates and testing patterns before, during, and after the COVID-19 pandemic. The relationships between testing and sex, age groups, chronic disease status, and hospital contacts were analyzed. We observed a marked decrease in cases of respiratory syncytial virus, influenza, and pneumococcus disease during the lockdown period. Once restrictions were lifted, there was a substantial resurgence in these infections. The frequency of testing for respiratory pathogens increased over time, with a rising proportion of healthy individuals without underlying chronic disease being tested. The proportion of positive tests linked to hospital contacts varied: there was a notable decline for respiratory syncytial virus and influenza post-lockdown, while pneumococcus cases continued to be strongly linked to hospital contacts. The study highlights the impact of COVID-19 interventions on the epidemiology of pediatric respiratory infections, revealing a pattern of decreased incidence during lockdowns followed by a resurgence. More tests were carried out among an increasing proportion of healthy individuals. Such changes in testing practices and changing characteristics of tested populations have implications for understanding post-pandemic infection trends and healthcare resource allocation.

The impact of risk compensation adaptive behavior on the final epidemic size.

Public health interventions reduce infection risk, while imposing significant costs on both individuals and the society. Interventions can also lead to behavioral changes, as individuals weigh the cost and benefits of avoiding infection. Aggregate epidemiological models typically focus on the population-level consequences of interventions, often not incorporating the mechanisms driving behavioral adaptations associated with interventions compliance. In this study, we use a behavior-epidemic model to analyze the consequences of detrimental behavioral responses driven by risk compensation. We analyze scenarios with varying levels of vaccine-acquired immunity and study the trade-off between risk compensation behaviors and reduced susceptibility. Our results reveal a trade-off between imperfect vaccine-acquired immunity and the potential risk compensation behavior of vaccinated individuals. We find that the impact of vaccination is ultimately influenced by the risk compensation behaviors of vaccinated individuals, which can either increase or decrease the size of the epidemic depending on the vaccine effectiveness. Moreover, we show that the behavioral response of the susceptible population modulates the impact of compensation behaviors by vaccinated individuals. Our results highlight that the distribution of highly protective vaccines can mitigate the observed effect. Additionally, they emphasize the importance of concurrently implementing non-pharmaceutical interventions in scenarios wherein vaccines have low efficacy. We extend our model by incorporating a model of disease surveillance, which drives a realistic operational course of action based on testing, analysis and response. Our results highlight the importance of robust surveillance systems in providing early warnings of disease outbreaks, which trigger early behavioral responses and timely interventions.

Efficacy of a group-based 8-week multicomponent cognitive training on cognition, mood and activities of daily living among healthy older adults: A two-year follow-up of a randomized controlled trial.

Cognitive training (CT) has been one of the important non-pharmaceutical interventions that could delay cognitive decline. Currently, no definite CT methods are available. Furthermore, little attention has been paid to the effect of CT on mood and instrumental activities of daily living (IADL). To assess the effectiveness of a multicomponent CT using a training program of executive functions, attention, memory and visuospatial functions (TEAM-V Program) on cognition, mood and instrumental ADL. A randomized, single-blinded, treatment-as-usual controlled trial. Geriatric clinic in Bangkok, Thailand. 80 nondemented community-dwelling older adults (mean age 65.7 ± 4.3 years). The CT (TEAM-V) Program or the treatment-as-usual controlled group. The TEAM-V intervention was conducted over 5 sessions, with a 2-week interval between each session. A total of 80 participants were randomized (n = 40 the TEAM-V Program; n = 40 the control group). The Thai version of Montreal Cognitive Assessment (MoCA), The Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog), Thai version of Hospital Anxiety and Depression Scale (HADS) and The Chula ADL were used to assess at baseline, 6 months, 1 year and 2 years. Compared with the control arm (n = 36), the TEAM-V Program (n = 39) was associated with significantly improved general cognition (MoCA, P = 0.02) at 2 years. Compared with baseline, participants receiving the TEAM-V Program were associated with significantly improved immediate recall (word recall task, P < 0.001), retrieval and retention of memory processes (word recognition task, P = 0.01) and attention (number cancellation part A, P = 0.01) at 2 years. No training effects on anxiety (P = 0.94), depression (P = 0.093) and IADL (P = 0.48) were detected. The TEAM-V Program was effective in improving global cognitive function. Even though, the program did not significantly improve anxiety, depression and IADL compared with the control group, memory and attention improved in the intervention group compared with baseline. Further studies incorporating a larger sample size, longitudinal follow-up and higher-intensity CT should be conducted.

Pandemic fatigue? Insights from road traffic in Hong Kong during COVID-19

ABSTRACT During the COVID-19 pandemic, voluntary adherence to non-pharmaceutical interventions (NPIs) was imperative to control the spread of the virus. The emergence of pandemic fatigue, however, may militate against public compliance with these interventions. Although existing literature has examined pandemic fatigue, little attention has been given to the spatio-temporal characteristics within a city. Focusing on the stay-at-home recommendation during COVID-19 in Hong Kong, this study employed road speed as a proxy to investigate pandemic fatigue. Temporally, the development of the pandemic and public concerns are investigated. Spatially, variables in four categories (i.e. socioeconomic, home environment, land use and COVID-related) are examined. Despite the same level of NPIs, changes in traffic were observed, indicating the emergence of pandemic fatigue. A positive correlation between adherence to NPIs and public interest in the ‘living with COVID’ policy is found. Spatially, areas with more older people demonstrated a high compliance rate. Findings suggest that by using road speed as a proxy for pandemic fatigue, potential factors in both spatial and temporal dimensions can be unveiled. Policy implications for future public health crises are also discussed.

Geosocial Media's Early Warning Capabilities Across US County-Level Political Clusters: Observational Study.

The novel coronavirus disease (COVID-19) sparked significant health concerns worldwide, prompting policy makers and health care experts to implement nonpharmaceutical public health interventions, such as stay-at-home orders and mask mandates, to slow the spread of the virus. While these interventions proved essential in controlling transmission, they also caused substantial economic and societal costs and should therefore be used strategically, particularly when disease activity is on the rise. In this context, geosocial media posts (posts with an explicit georeference) have been shown to provide a promising tool for anticipating moments of potential health care crises. However, previous studies on the early warning capabilities of geosocial media data have largely been constrained by coarse spatial resolutions or short temporal scopes, with limited understanding of how local political beliefs may influence these capabilities. This study aimed to assess how the epidemiological early warning capabilities of geosocial media posts for COVID-19 vary over time and across US counties with differing political beliefs. We classified US counties into 3 political clusters, democrat, republican, and swing counties, based on voting data from the last 6 federal election cycles. In these clusters, we analyzed the early warning capabilities of geosocial media posts across 6 consecutive COVID-19 waves (February 2020-April 2022). We specifically examined the temporal lag between geosocial media signals and surges in COVID-19 cases, measuring both the number of days by which the geosocial media signals preceded the surges in COVID-19 cases (temporal lag) and the correlation between their respective time series. The early warning capabilities of geosocial media data differed across political clusters and COVID-19 waves. On average, geosocial media posts preceded COVID-19 cases by 21 days in republican counties compared with 14.6 days in democrat counties and 24.2 days in swing counties. In general, geosocial media posts were preceding COVID-19 cases in 5 out of 6 waves across all political clusters. However, we observed a decrease over time in the number of days that posts preceded COVID-19 cases, particularly in democrat and republican counties. Furthermore, a decline in signal strength and the impact of trending topics presented challenges for the reliability of the early warning signals. This study provides valuable insights into the strengths and limitations of geosocial media data as an epidemiological early warning tool, particularly highlighting how they can change across county-level political clusters. Thus, these findings indicate that future geosocial media based epidemiological early warning systems might benefit from accounting for political beliefs. In addition, the impact of declining geosocial media signal strength over time and the role of trending topics for signal reliability in early warning systems need to be assessed in future research.

P-1965. Non-Pharmaceutical Interventions and Protection Against SARS-CoV-2 Infection in a Changing Pandemic Landscape

Abstract Background Non-pharmaceutical interventions (NPI), such as social distancing measures and the use of face masks, are presumed to lower the transmission of SARS-CoV-2. Guidance and mandates by public health authorities, however, have varied throughout the COVID-19 pandemic. This study sought to assess, on a population level, whether self-reported NPI measures were associated with the risk of SARS-CoV-2 infection at different times in the pandemic.Figure 1.Study data collection in relation to COVID-19 cases and pandemic milestone events in California in 2020-2022. The black solid line depicts newly reported COVID-19 cases in California across time. The grey shaded areas show the duration of the first and second shelter-in-place orders in California. The yellow shaded areas show the duration of the regional mask mandates in California. The light blue bars illustrate the cumulative weekly vaccination percentage across time. The red horizontal bars depict when CA-FACTS surveys were conducted. WHO; World Health Organization, CA; California. Methods We conducted a repeated cross-sectional study among randomly sampled households in 3 Northern California counties over 3 time points: Oct 2020-Mar 2021 (wave 1), Oct 2021-Feb 2022 (wave 2) and Mar-Jun 2022 (follow-up survey of wave 2 participants) (Figure 1). Social distancing, face mask use, vaccination status and self-reported COVID-19 were recorded by participants’ response in an online survey. We describe changes in NPI adoption across time and estimate the association of NPI and risk of COVID-19 infection among vaccinated individuals using logistic regression. Results The proportion of participants who reported never or rarely participating in social activities outside their household decreased from 60.2% in wave 1 to 20.5% in the follow-up survey. Similarly, face mask use decreased over time with 91.7% of wave 1 and 92.5% of wave 2 participants reporting consistently wearing a face mask in indoor public spaces compared to 66.4% of follow-up participants (Table 1). In multivariable regression models, social distancing was associated with significantly reduced odds of COVID-19 among vaccinated individuals in both surveys (wave 2 aOR 0.53, 95%CI 0.33-0.81; follow-up aOR 0.20, 95%CI 0.08-0.40). Consistent use of face masks tended to be less in those with self-reported COVID-19 in wave 2 (adjusted odds ratio (aOR) 0.58, 95%CI 0.32-1.13) but showed little impact in the follow-up survey (aOR 0.96, 95%CI 0.65-1.44, Table 2). Conclusion Declines in protection offered by face masking coincided with the lifting of mask mandates and decreased adherence to face mask use in communities overall. In contrast, the importance of social distancing as a protective strategy against COVID-19 infection appeared to increase over time. NPI, particularly social distancing, should remain first-line approaches to preventing infection in future outbreaks. Disclosures All Authors: No reported disclosures

P-636. Medical Need for Meningococcal Vaccination in Young Children from the Americas

Abstract Background Invasive meningococcal disease (IMD), caused mainly by Neisseria meningitidis serogroups (Men) A, B, C, W, X, and Y, is an uncommon but serious condition that can lead to life-long sequelae and is fatal in up to 20% of cases even with treatment. IMD incidence is highest in children &amp;lt;5 years. We present the current epidemiology of IMD in the Americas and unmet needs to reduce IMD burden in young children. Methods We reviewed the literature and available surveillance data from 2015 to 2024 to evaluate the IMD burden and national vaccination strategies for children &amp;lt; 5 years of age in the Americas. Results Overall, across countries, the incidence is highest in children aged &amp;lt;1 year, followed by children 1–4 years of age. MenB is the predominant serogroup in children &amp;lt; 5 years. In most countries with available data, IMD incidence decreased sharply during the COVID-19 pandemic but increased again after nonpharmaceutical interventions were lifted. Most countries do not have recommendations for routine meningococcal vaccination in children &amp;lt;5 years (Figure). Chile is the only country in the Americas that has routine vaccination against 5 serogroups, by including both MenACWY (2014) and MenB (2023) vaccinations in its national immunization program (NIP). The Argentinian, Brazilian, and Cuban NIPs include MenACWY (2017), MenC (2010), and MenBC (1991) vaccinations in infants, respectively. In Canada, MenC vaccination has been recommended for all infants since 2002, with one province (Manitoba) introducing MenACWY in 2024; MenB vaccination is recommended on an individual basis. Following introduction in the NIP/national recommendations, the incidence of IMD caused by serogroups covered by the vaccines has decreased in these countries. In the United States, MenACWY vaccination is recommended in children at high risk of IMD, but not for routine vaccination in &amp;lt;5-year olds. Conclusion Considering the current incidence and burden of IMD in infants &amp;lt; 1 and children &amp;lt; 5 years of age across the region, especially MenB-IMD, comprehensive IMD vaccination programs could reduce the overall burden in this population. NIPs/national recommendations would facilitate equitable access to protection against IMD, aligned to the World Health Organization roadmap to defeat meningitis by 2030. Funding: GSK Disclosures Gaurav Mathur, MD, GSK: Employee|GSK: Stocks/Bonds (Private Company)|OpenHealth: Writing support Maria Gabriela Graña, MD, GSK: employment|GSK: Stocks/Bonds (Private Company) Reena Ladak, MS, GSK: Employee|GSK: Stocks/Bonds (Private Company) Joanne M. Langley, MD, GSK: Grant/Research Support|Inventprise: Grant/Research Support|Merck: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support|VBI: Grant/Research Support|VIDO: Grant/Research Support Oluwatosin Olaiya, MBChB, MSc, GSK: employment (current)|Merck: Previous employer Alysa Pompeo, BPharm, GSK: employment Laura Taddei, M.Sc, GSK: GSK employment|GSK: Stocks/Bonds (Public Company) Rodolfo Villena, MD, GSK: Advisor/Consultant|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support

P-697. Increases in Ages and Bacterial Coinfection in Hospitalized Children with Respiratory Syncytial Virus Infection in Taiwan:2019- 2023

Abstract Background Efforts to expand RSV epidemiological data are crucial, especially considering upcoming interventions such as long-acting monoclonal RSV-neutralizing antibodies and maternal vaccines for RSV prevention, which have the potential to alter the landscape. Methods A retrospective study was conducted at Chang Gung Memorial Hospital, analyzing children hospitalized with RSV infection before, during and after the COVID-19 pandemics from 2019 to 2023. Clinical data were collected and stratified by year for analysis. Plasma microbial free-DNA sequencing (mcfDNA) was performed on selected cases with C-reactive protein &amp;gt; 100 mg/L to enhance diagnostic yields. Results A total of 997 children hospitalized for RSV infection was enrolled. In 2019, 2022, and 2023, the incidence of RSV-related hospitalization among children aged 0-4 years remained relatively stable, ranging between 600-700 per 100,000. However, in 2020 during a strict national nonpharmaceutical intervention, there was a notable spike, doubling to reach a peak, followed by an 80% decrease in 2021. In age subgroup analyses comparing 2022 and 2023 to 2019, the incidence of RSV-related hospitalization among children aged &amp;lt; 2 years gradually decreased from 1576 per 100,000 in 2019 to 1212 per 100,000 in 2022 (P=0.03) and 1262 per 100,000 (P=0.07) in 2023. Conversely, the incidence of RSV-related hospitalization among children aged 2-4 years significantly increased from 124 per 100,000 in 2019 to 347 per 100,000 in 2022 (P&amp;lt; 0.001) and 419 per 100,000 in 2023 (P&amp;lt; 0.001). Independent risk factors for CRP &amp;gt;100 mg/L in RSV cases were year 2023 (aOR:4.03, P=0.008) and age 2-4 years (aOR:3.33, P&amp;lt; 0.001). In 2023, among 23 children with CRP &amp;gt;100 mg/L, Hemophilus influenzae was identified in two children receiving bronchoalveolar lavage, and in 73% (11/15) of samples underwent plasma mcfDNA. Conclusion Following the COVID-19 pandemic, there was a proportional shift in RSV cases towards children over 2 years of age. Increase in age exhibited a higher rate of bacterial infections, particularly with Haemophilus influenzae. These findings offer critical implication for RSV prevention strategies and treatment of community-acquired pneumonia. Disclosures All Authors: No reported disclosures

P-1210. Resurgence of Parechovirus-A3 Infection in Neonates and Young Infants after the Coronavirus Disease 2019 Pandemic in Japan

Abstract Background Parechovirus-A (PeV-A), especially PeV-A3, is a common cause of viral sepsis and encephalitis in neonates and young infants (age &amp;lt; 4 months). The strict infection control measures and non-pharmaceutical interventions of the coronavirus disease 2019 (COVID-19) pandemic affected the epidemiological profiles of community-acquired diseases. However, the effects of the pandemic on the epidemiology of PeV-A infection in this age group are unknown. Methods This prospective multicenter observational study was conducted between 2019 and 2023 in 12 Japanese prefectures. Neonates and young infants hospitalized for suspected sepsis and/or meningoencephalitis were included. Samples were sent to the laboratory of Niigata University, and PeV-A was detected by real-time PCR. The 7 hospitals introduced the BioFire Filmarray meningitis/encephalitis (FA/ME) panel in 2020. Genotype was determined by direct sequencing and BLAST analysis, and the phylogenetic tree of viral protein 1 region of PeV-A3 was constructed. Results 131 patients with PeV-A infection were identified (n = 36 in 2019, n = 7 in 2020, n = 1 in 2021, n = 27 in 2022, and n = 60 in 2023). Genotype was PeV-A3 in 124 cases and PeV-A4 in 2 cases in 2022 and unknown in 5 cases in 2019. Seasonal peaks and other characteristics were similar before and after the COVID-19 pandemic (i.e., in 2019 vs. 2023). Body temperature, fever duration, and the proportion of patients with rash declined; however, the proportion of those with abdominal distention increased. The FA/ME panel was more frequently used after the start of the pandemic (3.2% vs. 53.3%, P &amp;lt; 0.001). The proportion of those with sepsis declined from 83.9% to 63.3% (P = 0.04), but the proportions of those with encephalitis and those requiring ICU admission were similar. No patient had sequelae at discharge. PeV-A3 has evolved within a single clade with two branches. Conclusion The number of PeV-A3 infections was higher after the start of the COVID-19 pandemic, possibly because low PeV-A3 activity early in the pandemic increased the number of susceptible pregnant women, thus leading to a decline in maternally derived antibodies. In addition, use of the FA/ME panel might help detect mild cases. Disclosures All Authors: No reported disclosures

Dispersal dynamics and introduction patterns of SARS-CoV-2 lineages in Iran

Abstract Understanding the dispersal patterns of SARS-CoV-2 lineages is crucial to public health decision-making, especially in countries with limited access to viral genomic sequencing. This study provides a comprehensive epidemiological and phylodynamic perspective on SARS-CoV-2 lineage dispersal in Iran from February 2020 to July 2022. We explored the genomic epidemiology of SARS-CoV-2 combining 1,281 genome sequences with spatial data in a phylogeographic framework. Our analyses shed light on multiple international imports seeding subsequent waves and on domestic dispersal dynamics. Lineage B.4 was identified to have been circulating in Iran 29 days (95% HPD, interval: 21-47) before non-pharmaceutical interventions were implemented. The importation dynamics throughout subsequent waves were primarily driven from the country or region where the variant was first reported and gradually shifted to other regions. At the national level, Tehran was the main source of dissemination across the country. Our study highlights the crucial role of continuous genomic surveillance and international collaboration for future pandemics preparedness and efforts to control viral transmission.

Verification of Immune Debts in Children Caused by the COVID-19 Pandemic from an Epidemiological and Clinical Perspective

Social behavior restrictions, social distancing, and promotion of non-pharmaceutical interventions (NPIs) during the COVID-19 pandemic have significantly reduced the incidence of many epidemic infections in the world, especially in children. Resurges of infectious diseases vary depending on the biological characteristics of each infectious pathogen and differences in culture, lifestyle, and infection control mitigation policies by country or region. Although the gapping of infectious disease outbreaks can cause children who were uninfected during that period to become more susceptible to infection after the pandemic, resulting in a slightly older age of infected children, there are no conclusive reports that suggest a definite impact on the development of children’s immune maturation or its balance. Insufficient immune challenges in early life may influence the risk of developing immune-mediated conditions such as allergies or autoimmune diseases later in life, though evidence for this is still emerging. Future observational studies are needed to determine the long-term impact of the epidemic gap caused by the COVID-19 pandemic as well as the long-term impact of COVID-19 infection itself on the immune function or balance of children.