Masks and respirators for prevention of respiratory infections: a state of the science review.

SUMMARYThis narrative review and meta-analysis summarizes a broad evidence base on the benefits-and also the practicalities, disbenefits, harms and personal, sociocultural and environmental impacts-of masks and masking. Our synthesis of evidence from over 100 published reviews and selected primary studies, including re-analyzing contested meta-analyses of key clinical trials, produced seven key findings. First, there is strong and consistent evidence for airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory pathogens. Second, masks are, if correctly and consistently worn, effective in reducing transmission of respiratory diseases and show a dose-response effect. Third, respirators are significantly more effective than medical or cloth masks. Fourth, mask mandates are, overall, effective in reducing community transmission of respiratory pathogens. Fifth, masks are important sociocultural symbols; non-adherence to masking is sometimes linked to political and ideological beliefs and to widely circulated mis- or disinformation. Sixth, while there is much evidence that masks are not generally harmful to the general population, masking may be relatively contraindicated in individuals with certain medical conditions, who may require exemption. Furthermore, certain groups (notably D/deaf people) are disadvantaged when others are masked. Finally, there are risks to the environment from single-use masks and respirators. We propose an agenda for future research, including improved characterization of the situations in which masking should be recommended or mandated; attention to comfort and acceptability; generalized and disability-focused communication support in settings where masks are worn; and development and testing of novel materials and designs for improved filtration, breathability, and environmental impact.

Epidemiology and viral loads of respiratory syncytial virus in hospitalized children prior to and during COVID-19 pandemic in Hangzhou, China.

Non-pharmaceutical interventions (NPIs) implemented to control SARS-CoV-2 have significantly influenced the activity of respiratory pathogens. This study investigated epidemiological changes among hospitalized patients with respiratory syncytial virus (RSV) before (2017-2019) and during (2020-2022) the COVID-19 pandemic in Hangzhou, China. We also examined viral load distribution across demographic and temporal variables. Nasopharyngeal swabs were collected and RSV loads were quantified using reverse transcriptase polymerase chain reaction (RT-qPCR). RSV epidemic characteristics, seasonal dynamics, and viral load distributions were compared between pre- and pandemic years. General linear models were employed to assess associations between viral loads and age. Among 19 742 cases, 1576 and 2092 tested positive during the pre- and pandemic years, respectively. From February to July 2020, the implementation of NPIs led to the cessation of RSV circulation. However, after these measures were relaxed, RSV cases resurged over two consecutive seasons during the pandemic, notably affecting older children compared to those in the pre-pandemic years (1.00 years, IQR: 0.50-2.00 vs. 0.58 years, IQR: 0.27-1.00, p < 0.001). Specifically, in 2021-2022, an off-season resurgence of RSV began earlier (mid-June), lasted longer (40 weeks), and involved more positive cases (1238 cases) than both 2020-2021 and pre-pandemic years. Viral load distribution demonstrated a clear age-related relationship in both pre- and pandemic years, with younger children consistently showing higher viral loads, independently of gender and season (all p-values for trends <0.001). These findings highlight the impact of NPIs on RSV epidemiology and underscore the need to prioritize RSV infection prevention in younger children from the perspective of viral load.

COVID Protection Behaviors, Mental Health, Risk Perceptions, and Control Beliefs: A Dynamic Temporal Network Analysis of Daily Diary Data.

BACKGROUND: To control infections, behavioral non-pharmaceutical interventions (NPIs) such as social distancing and hygiene measures (masking, hand hygiene) were implemented widely during the COVID-19 pandemic. At the same time, adherence to NPIs has also been implied in an increase in mental health problems. However, the designs of many existing studies are often poorly suited to disentangle complex relationships between NPI adherence, mental health symptoms, and health-related cognitions (risk perceptions, control beliefs). PURPOSE: To separate between- and temporal within-person associations between mental health, health-related cognitions, and NPI adherence. METHODS: Six-month ecological momentary assessment (EMA) study with six 4-day assessment bouts in 397 German adults. Daily measurement of adherence, mental health symptoms, and cognitions during bouts. We used dynamic temporal network analysis to estimate between-person, as well as contemporaneous and lagged within-person effects for distancing and hygiene NPIs. RESULTS: Distinct network clusters of mental health, health cognitions, and adherence emerged. Participants with higher control beliefs and higher susceptibility were also more adherent (between-person perspective). Within-person, similar findings emerged, additionally, distancing and loneliness were associated. Lagged findings suggest that better adherence to NPIs was associated with better mental health on subsequent days, whereas higher loneliness was associated with better subsequent hygiene adherence. CONCLUSIONS: Findings suggest no negative impact of NPI adherence on mental health or vice versa, but instead suggest that adherence might improve mental health symptoms. Control beliefs and risk perceptions are important covariates of adherence-both on between-person and within-person level.

Adhering to COVID protective behaviors might be less detrimental for mental health than some previous claims: Over 6 months in 2021­2022, adults from Germany who adhered to COVID protection recommendations (mask-wearing, hand hygiene, social distancing) on any one day reported better mental health the following days.

Impact of non-pharmaceutical interventions during the COVID-19 pandemic on pathogens transmitted via food in the Netherlands.

The COVID-19 pandemic impacted the transmission of many pathogens. The aim was to determine the effect of non-pharmaceutical interventions on the incidence of diseases transmitted via food. Weekly incidence rates for nine foodborne pathogens were collected from national surveillance registries. Weekly pathogen incidence during lockdown weeks of 2020 and 2021 were compared with corresponding weeks in 2015-2019. The same analyses were performed to determine the effect of self-defined expected impact levels of measures (low, intermediate and high). Eight out of 9 diseases showed a significant decrease in case number in 2020, except for listeriosis, which remained unchanged. The largest decrease was observed for rotavirus gastronteritis A (-81%), norovirus gastroenteritis (-78%), hepatitis A (-75%) and shigellosis (-72). In 2021, lower case numbers were observed for 6 out of 9 diseases compared with 2015-2019, with the largest decrease for shigellosis (-5/%) and hepatitis E (-47%). No significant change was observed for listeriosis, STEC infection and rotavirus gastroenteritis. Overall, measures with increased expected impact level did not result in a larger decrease in number of cases, except for Campylobacter, and norovirus and rotavirus gastroenteritis. Disease transmitted via food significantly decreased during the COVID-19 pandemic, with a more pronounced effect during 2020 than 2021.

Mycoplasma pneumoniae detections in children with lower respiratory infection before and during the COVID-19 pandemic: a large sample study in China from 2019 to 2022.

BACKGROUND: Nonpharmaceutical interventions (NPIs) implemented to reduce the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have suppressed the spread of other respiratory viruses during the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to explore the epidemiological trends and clinical characteristics of Mycoplasma pneumoniae (MP) infection among inpatient children with lower respiratory tract infection (LRTI) before and during the COVID-19 pandemic, and investigate the long-term effects of China's NPIs against COVID-19 on the epidemiology of MP among inpatient children with LRTI. METHODS: Children hospitalised for LRTI at the Department of Pulmonology, The Children's Hospital, Zhejiang University School of Medicine (Hangzhou, China) between January 2019 and December 2022 were tested for common respiratory pathogens, including Mycoplasma pneumoniae (MP), Chlamydia trachomatis (CT) and other bacteria. Clinical data on age, sex, season of onset, disease spectrum, and combined infection in children with MP-induced LRTI in the past 4 years were collected and analysed. RESULTS: Overall, 15909 patients were enrolled, and MP-positive cases were 1971 (34.0%), 73 (2.4%), 176 (5.8%), and 952 (20.6%) in 2019, 2020, 2021, and 2022, respectively, with a significant statistical difference in the MP-positive rate over the 4 years (p <0.001). The median age of these children was preschool age (3-6 years), except for 2022, when they were school age (7-12 years), with statistical differences. Comparing the positive rates of different age groups, the school-age children (7-12 years) had the highest positive rate, followed by the preschoolers (3-6 years) in each of the 4 years. Compared among different seasons, the positive rate of MP in children with LRTI was higher in summer and autumn, whereas in 2020, it was highest in spring. The monthly positive rate peaked in July 2019, remained low from 2020 to 2021, and rebounded until 2022. Regarding the disease spectrum, severe pneumonia accounted for the highest proportion (46.3%) pre-pandemic and lowest (0%) in 2020. CONCLUSION: Trends in MP detection in children with LRTIs suggest a possible correlation between COVID-19 NPIs and significantly reduced detection rates. The positivity rate of MP gradually rose after 2 years. The epidemic season showed some differences, but school-age children were more susceptible to MP before and during the COVID-19 pandemic.

Understanding the secondary outcomes of international travel measures during the covid-19 pandemic: a scoping review of social impact evidence.

BACKGROUND: Assessment of the effective use of international travel measures during the COVID-19 pandemic has focused on public health goals, namely limiting virus introduction and onward transmission. However, risk-based approaches includes the weighing of public health goals against potential social, economic and other secondary impacts. Advancing risk-based approaches thus requires fuller understanding of available evidence on such impacts. METHODS: We conducted a scoping review of existing studies of the social impacts of international travel measures during the COVID-19 pandemic. Applying a standardized typology of travel measures, and five categories of social impact, we searched 9 databases across multiple disciplines spanning public health and the social sciences. We identified 26 studies for inclusion and reviewed their scope, methods, type of travel measure, and social impacts analysed. RESULTS: The studies cover a diverse range of national settings with a strong focus on high-income countries. A broad range of populations are studied, hindered in their outbound or inbound travel. Most studies focus on 2020 when travel restrictions were widely introduced, but limited attention is given to the broader effects of their prolonged use. Studies primarily used qualitative or mixed methods, with adaptations to comply with public health measures. Most studies focused on travel restrictions, as one type of travel measure, often combined with domestic public health measures, making it difficult to determine their specific social impacts. All five categories of social impacts were observed although there was a strong emphasis on negative social impacts including family separation, decreased work opportunities, reduced quality of life, and inability to meet cultural needs. A small number of countries identified positive social impacts such as restored work-life balance and an increase in perceptions of safety and security. CONCLUSIONS: While international travel measures were among the most controversial interventions applied during the COVID-19 pandemic, given their prolonged use and widespread impacts on individuals and populations, there remains limited study of their secondary impacts. If risk-based approaches are to be advanced, involving informed choices between public health and other policy goals, there is a need to better understand such impacts, including their differential impacts across diverse populations and settings.

Modelling the impact of precaution on disease dynamics and its evolution.

In this paper, we introduce the notion of practically susceptible population, which is a fraction of the biologically susceptible population. Assuming that the fraction depends on the severity of the epidemic and the public's level of precaution (as a response of the public to the epidemic), we propose a general framework model with the response level evolving with the epidemic. We firstly verify the well-posedness and confirm the disease's eventual vanishing for the framework model under the assumption that the basic reproduction number R 0 < 1 . For R 0 > 1 , we study how the behavioural response evolves with epidemics and how such an evolution impacts the disease dynamics. More specifically, when the precaution level is taken to be the instantaneous best response function in literature, we show that the endemic dynamic is convergence to the endemic equilibrium; while when the precaution level is the delayed best response, the endemic dynamic can be either convergence to the endemic equilibrium, or convergence to a positive periodic solution. Our derivation offers a justification/explanation for the best response used in some literature. By replacing "adopting the best response" with "adapting toward the best response", we also explore the adaptive long-term dynamics.

Non-pharmaceutical interventions to reduce COVID-19 transmission in the UK: a rapid mapping review and interactive evidence gap map.

BACKGROUND: Non-pharmaceutical interventions (NPIs) were crucial in the response to the COVID-19 pandemic, although uncertainties about their effectiveness remain. This work aimed to better understand the evidence generated during the pandemic on the effectiveness of NPIs implemented in the UK. METHODS: We conducted a rapid mapping review (search date: 1 March 2023) to identify primary studies reporting on the effectiveness of NPIs to reduce COVID-19 transmission. Included studies were displayed in an interactive evidence gap map. RESULTS: After removal of duplicates, 11 752 records were screened. Of these, 151 were included, including 100 modelling studies but only 2 randomized controlled trials and 10 longitudinal observational studies.Most studies reported on NPIs to identify and isolate those who are or may become infectious, and on NPIs to reduce the number of contacts. There was an evidence gap for hand and respiratory hygiene, ventilation and cleaning. CONCLUSIONS: Our findings show that despite the large number of studies published, there is still a lack of robust evaluations of the NPIs implemented in the UK. There is a need to build evaluation into the design and implementation of public health interventions and policies from the start of any future pandemic or other public health emergency.

Changes in social mixing and attitudes and practices to precautionary measures in a maturing COVID-19 pandemic in six communities in Sudan: a qualitative study.

INTRODUCTION: With low COVID-19 vaccination coverage, non-pharmaceutical interventions were critical to mitigating the COVID-19 pandemic in Sudan. We explored changes in social contact patterns, risk perception, attitudes, and practices toward protective measures during an evolving COVID-19 outbreak in six illustrative communities in Sudan. METHODS: This qualitative study took place in six communities in five Sudanese states using focus group discussions with community members and non-participant structured observations in public spaces between March 2021 and April 2021. A total of 117 participants joined 24 group discussions. We used a two-stage thematic analysis. RESULTS: The perceived importance of compliance with individual preventative measures among those who believe in COVID-19 was higher than observed compliance with behaviors in most study sites. Adherence was consistently low and mainly driven by enforced movement restrictions. As restrictions were lifted, social contacts outside the household resumed pre-COVID-19 levels, and risk perception and individual and institutional adherence to protective measures diminished. We identified an environment that is socially and economically unsupportive of preventive practices, compounded by widespread rumours, misinformation, and mistrust in the government-led response. However, we identified new social habits that can contribute to reducing COVID-19 transmission. CONCLUSION: The unfavourable social and economic environment, coupled with the low visibility of the pandemic and pandemic response, has likely modulated the influence of higher risk perception on adopting precautionary behaviours by individuals. Governments and non-governmental actors should increase the visibility of the pandemic and pandemic response, enforce and incentivise infection control measures in public areas, promote emerging preventive social habits, and actively track and address rumours and misinformation related to COVID-19 and COVID-19 vaccines.

Non-pharmaceutical interventions in containing COVID-19 pandemic after the roll-out of coronavirus vaccines: a systematic review.

BACKGROUND: Non-pharmaceutical interventions (NPIs) have been widely utilised to control the COVID-19 pandemic. However, it is unclear what the optimal strategies are for implementing NPIs in the context of coronavirus vaccines. This study aims to systematically identify, describe, and evaluate existing ecological studies on the real-world impact of NPIs in containing COVID-19 pandemic following the roll-out of coronavirus vaccines. METHODS: We conducted a comprehensive search of relevant studies from January 1, 2021, to June 4, 2023 in PubMed, Embase, Web of science and MedRxiv. Two authors independently assessed the eligibility of the studies and extracted the data. A risk of bias assessment tool, derived from a bibliometric review of ecological studies, was applied to evaluate the study design, statistical methodology, and the quality of reporting. Data were collected, synthesised and analysed using qualitative and quantitative methods. The results were presented using summary tables and figures, including information on the target countries and regions of the studies, types of NPIs, and the quality of evidence. RESULTS: The review included a total of 17 studies that examined the real-world impact of NPIs in containing the COVID-19 pandemic after the vaccine roll-out. These studies used five composite indicators that combined multiple NPIs, and examined 14 individual NPIs. The studies had an average quality assessment score of 13 (range: 10-16), indicating moderately high quality. NPIs had a larger impact than vaccination in mitigating the spread of COVID-19 during the early stage of the vaccination implementation and in the context of the Omicron variant. Testing policies, workplace closures, and restrictions on gatherings were the most effective NPIs in containing the COVID-19 pandemic, following the roll-out of vaccines. The impact of NPIs varied across different time frames, countries and regions. CONCLUSION: NPIs had a larger contribution to the control of the pandemic as compared to vaccination during the early stage of vaccine implementation and in the context of the omicron variant. The impact of NPIs in containing the COVID-19 pandemic exhibited variability in diverse contexts. Policy- and decision-makers need to focus on the impact of different NPIs in diverse contexts. Further research is needed to understand the policy mechanisms and address potential future challenges.

Impact of non-pharmaceutical interventions on COVID-19 incidence and deaths: cross-national natural experiment in 32 European countries.

PURPOSE: Non-pharmaceutical interventions (NPIs) have been the cornerstone of COVID-19 pandemic control, but evidence on their effectiveness varies according to the methods and approaches taken to empirical analysis. We analysed the impact of NPIs on incident SARS-CoV-2 across 32 European countries (March-December 2020) using two NPI trackers: the Corona Virus Pandemic Policy Monitor - COV-PPM, and the Oxford Covid-19 Government Response Tracker - OxCGRT. METHODS: NPIs were summarized through principal component analysis into three sets, stratified by two waves (C1-C3, weeks 5-25, and C4-C6, weeks 35-52). Longitudinal, multi-level mixed-effects negative binomial regression models were fitted to estimate incidence rate ratios for cases and deaths considering different time-lags and reverse causation (i.e. changing incidence causing NPIs), stratified by waves and geographical regions (Western, Eastern, Northern, Southern, Others). RESULTS: During the first wave, restrictions on movement/mobility, public transport, public events, and public spaces (C1) and healthcare system improvements, border closures and restrictions to public institutions (C2) were associated with a reduction in SARS-CoV-2 incidence after 28 and 35-days. Mask policies (C3) were associated with a reduction in SARS-CoV-2 incidence (except after 35-days). During wave 1, C1 and C2 were associated with a decrease in deaths after 49-days and C3 after 21, 28 and 35-days. During wave 2, restrictions on movement/mobility, public transport and healthcare system improvements (C5) were also associated with a decrease in SARS-CoV-2 cases and deaths across all countries. CONCLUSION: In the absence of pre-existing immunity, vaccines or treatment options, our results suggest that the observed implementation of different categories of NPIs, showed varied associations with SARS-CoV-2 incidence and deaths across regions, and varied associations across waves. These relationships were consistent across components of NPIs derived from two policy trackers (CoV-PPM and OxCGRT).

The impact of non-pharmaceutical interventions on community non-SARS-CoV-2 respiratory infections in preschool children.

BACKGROUND: Effects of non-pharmaceutical interventions during the pandemic were mainly studied for severe outcomes. Among children, most of the burden of respiratory infections is related to infections which are not medically attended. The perspective on infections in the community setting is necessary to understand the effects of the pandemic on non-pharmaceutical interventions. METHODS: In the unique prospective LoewenKIDS cohort study, we compared the true monthly incidence of self-reported acute respiratory infections (ARI) in about 350 participants (aged 3-4 years old) between October 2019 to March 2020 (pre-pandemic period) and October 2020 to March 2021 (pandemic period). Parents reported children's symptoms using a diary. Parents were asked to take a nasal swab of their child during all respiratory symptoms. We analysed 718 swabs using Multiplex PCR for 25 common respiratory viruses and bacteria. RESULTS: During the pre-pandemic period, on average 44.6% (95% CI: 39.5-49.8%) of children acquired at least one ARI per month compared to 19.9% (95% CI: 11.1-28.7%) during the pandemic period (Incidence Rate Ratio = 0.47; 95% CI: 0.41-0.54). The detection of influenza virus decreased absolute by 96%, respiratory syncytial virus by 65%, metapneumovirus by 95%, parainfluenza virus by 100%, human enterovirus by 96% and human bocavirus by 70% when comparing the pre-pandemic to the pandemic period. However, rhinoviruses were nearly unaffected by NPI. Co-detection (detection of more than one virus in a single symptomatic swab) was common in the pre-pandemic period (222 of 390 samples with viral detection; 56.9%) and substantially less common during the pandemic period (46 of 216 samples; 21.3%). CONCLUSION: Non-pharmaceutical interventions strongly reduced the incidence of all respiratory infections in preschool children but did not affect rhinovirus.

A comparative analysis of non-pharmaceutical interventions for preventing the respiratory syncytial virus in 30 European countries.

AIM: Respiratory syncytial virus (RSV) is a leading cause of childhood respiratory infections. Non-pharmaceutical interventions (NPIs) can help to reduce RSV transmission and our aim was to provide an overview of recommended NPIs across Europe during the 2022-2023 epidemic season. METHODS: The webpages of national European public health agencies and ministries were reviewed and the information they provided on RSV prevention was compared with the December 2022 guidelines from the European Centre for Disease Prevention and Control. RESULTS: We examined 30 countries, leading to 21 issued recommendations for RSV prevention through institutional channels, including six that were specific for the 2022-2023 season. The top five recommendations were: hand and respiratory hygiene (95%), avoiding crowded spaces (67%), staying at home when ill (62%), cleaning household items (57%) and limiting contact with sick people (57%). They also included: face masks (33%), ventilating indoor spaces (29%), properly disposing of contaminated material (13%) and keeping siblings home from preschool if there was a newborn infant in the family (10%). CONCLUSION: There was significant heterogeneity in the NPIs recommended by different countries during RSV epidemics. Ongoing evaluation is essential to optimise the effectiveness of NPIs and adapt to changing RSV patterns.

Time trends and modifiable factors of COVID-19 contact tracing coverage, Geneva, Switzerland, June 2020 to February 2022.

BackgroundContact tracing was one of the central non-pharmaceutical interventions implemented worldwide to control the spread of SARS-CoV-2, but its effectiveness depends on its ability to detect contacts.AimEvaluate the proportion of secondary infections captured by the contact tracing system in Geneva.MethodsWe analysed 166,892 concomitant infections occurring at the same given address from June 2020 until February 2022 using an extensive operational database of SARS-CoV-2 tests in Geneva. We used permutation to compare the total number of secondary infections occurring at the same address with that reported through manual contact tracing.ResultsContact tracing captured on average 41% of secondary infections, varying from 23% during epidemic peaks to 60% during low epidemic activity. People living in wealthy neighbourhoods were less likely to report contacts (odds ratio (OR): 1.6). People living in apartment buildings were also less likely to report contacts than those living in a house (OR: 1.1-3.1) depending on the SARS-CoV-2 variant, the building size and the presence of shops. This under-reporting of contacts in apartment buildings decreased during periods of mandatory wearing of face masks and restrictions on private gatherings.ConclusionContact tracing alone did not detect sufficient secondary infections to reduce the spread of SARS-CoV-2. Campaigns targeting specific populations, such as those in wealthy areas or apartment buildings, could enhance coverage. Additionally, measures like wearing face masks, improving ventilation and implementing restrictions on gatherings should also be considered to reduce infections resulting from interactions that may not be perceived as high risk.

New atypical epidemiological profile of parvovirus B19 revealed by molecular screening of blood donations, France, winter 2023/24.

In France, blood donations are tested in pools of 96 samples for parvovirus B19 (B19V) DNA to discard plasma for fractionation when it contains high viral loads. Between January 2015 and March 2024, B19V-positive donations decreased during the COVID-19 pandemic, followed by a strong rebound in 2023 and unusually high circulation during winter 2023/24 (ca 10 times higher December 2023-March 2024 vs the pre-pandemic period). Variations over time are probably related to measures implemented to limit SARS-CoV-2 spread.

Secondary infections of COVID-19 in schools and the effectiveness of school-based interventions: a systematic review and meta-analysis.

OBJECTIVES: This meta-analysis explored secondary infections of SARS-CoV-2 and the effectiveness of non-pharmaceutical interventions (NPIs) in school settings, with the aim of providing a reference to formulate scientific prevention and response strategies for similar major public health emergencies in specific settings. STUDY DESIGN: This was a systematic review and meta-analysis. METHODS: Systematic searches were conducted in PubMed, Web of Science and the Cochrane Library through to 1 August 2022 using the following key search terms: COVID-19, SARS-CoV-2, secondary attack rate, school, transmission, etc. The IVhet model was used for the meta-analysis, and the I2 index and Cochran's Q-test were used to assess heterogeneity. Publication bias was examined using Doi plot, Galbraith plots and Luis Furuya-Kanamori index. Prevalence Critical Appraisal Tool was used to assess the quality of the included articles, while Grading of Recommendations Assessment, Development, and Evaluation was used to rate the quality of the evidence. Subgroup analyses were conducted to explore the potential source of heterogeneity. RESULTS: Thirty-four studies involving 226,727 school contacts and 2216 secondary cases were included in this study. The pooled secondary attack rates (SARs) of close contacts, staff contacts and student contacts were 0.67% (95% confidence interval [CI]: 0.11, 1.56), 0.79% (95% CI: 0.00, 6.72) and 0.50% (95% CI: 0.00, 4.48), respectively. Subgroup analysis suggested that multiple or specific combinations (e.g. the combination of contact restriction and hygiene action) of NPIs appeared to be associated with lower SARs. CONCLUSIONS: The SAR of SARS-CoV-2 was low in schools. Multiple or specific combinations of prevention strategies appear to mitigate SARS-CoV-2 transmission in school settings. These findings provide a basis for continuous improvement of response strategies to major public health emergencies in the school environment.

Safe Sex and the Debate over Condoms on Campus in the 1980s: Sperm Busters at Harvard and Protection Connection at the University of Texas at Austin.

During the 1980s, college students in the United States helped to destigmatize the distribution and use of condoms. They shifted their aims from preventing unwanted pregnancy to stopping the spread of sexually transmitted infections including the newly identified acquired immunodeficiency syndrome (AIDS). Two student-led initiatives to deliver condoms after hours at Harvard University in Cambridge, Massachusetts and the University of Texas at Austin show regional and temporal differences in sexual mores as awareness of AIDS increased. These male students adopted a non-pharmaceutical intervention to prevent pregnancy and disease in the context of increased marketing of Trojan® brand condoms. Interviews with co-founders reveal how the students grappled with backlash from family members and campus administrators less enthusiastic about their popularization of condoms. Co-founders described how media attention affected their college experiences and how condom companies changed campus culture. Overall, large non-pharmaceutical companies such as Trojan® and small condom-resellers such as those at Harvard and the University of Texas at Austin reshaped cultural norms around safe sex as awareness of AIDS grew between 1985 and 1987.

The Ethical Obligation for Research During Public Health Emergencies: Insights From the COVID-19 Pandemic.

In times of crises, public health leaders may claim that trials of public health interventions are unethical. One reason for this claim can be that equipoise-i.e. a situation of uncertainty and/or disagreement among experts about the evidence regarding an intervention-has been disturbed by a change of collective expert views. Some might claim that equipoise is disturbed if the majority of experts believe that emergency public health interventions are likely to be more beneficial than harmful. However, such beliefs are not always justified: where high quality research has not been conducted, there is often considerable residual uncertainty about whether interventions offer net benefits. In this essay we argue that high-quality research, namely by means of well-designed randomized trials, is ethically obligatory before, during, and after implementing policies in public health emergencies (PHEs). We contend that this standard applies to both pharmaceutical and non-pharmaceutical interventions, and we elaborate an account of equipoise that captures key features of debates in the recent pandemic. We build our case by analyzing research strategies employed during the COVID-19 pandemic regarding drugs, vaccines, and non-pharmaceutical interventions; and by providing responses to possible objections. Finally, we propose a public health policy reform: whenever a policy implemented during a PHE is not grounded in high-quality evidence that expected benefits outweigh harms, there should be a planned approach to generate high-quality evidence, with review of emerging data at preset time points. These preset timepoints guarantee that policymakers pause to review emerging evidence and consider ceasing ineffective or even harmful policies, thereby improving transparency and accountability, as well as permitting the redirection of resources to more effective or beneficial interventions.

The changed endemic pattern of human adenovirus from species B to C among pediatric patients under the pressure of non-pharmaceutical interventions against COVID-19 in Beijing, China.

BACKGROUND: Under the pressure of non-pharmaceutical interventions (NPIs) targeting severe acute respiratory syndrome coronavirus 2, the prevalence of human adenovirus (HAdV) was monitored before and after NPIs launched on Jan 24, 2020 in pediatric patients in Beijing, China. METHODS: Respiratory samples collected from children hospitalized with acute respiratory infections from Jan 2015 to Dec 2021 were screened by direct immunofluorescence test or capillary electrophoresis-based multiplex PCR assay. The hexon, penton base, and fiber genes were amplified from HAdV positive specimens, then sequenced. For HAdV typing, phylogenetic trees were built by MEGA X. Then clinical data of HAdV positive cases were collected. All data were evaluated using SPSS Statistics 22.0 software. RESULTS: A total of 16,097 children were enrolled and 466 (2.89%, 466/16,097) were HAdV-positive. The positive rates of HAdV varied, ranging from 4.39% (151/3,438) in 2018 to1.25% (26/2,081) in 2021, dropped from 3.19% (428/13,408) to 1.41% (38/2,689) from before to after NPIs launched (P < 0.001). There were 350 cases typed into nine types of species B, C, or E and 34 recorded as undetermined. Among them, HAdV-B3 (51.56%, 198/384) was the most prevalent types from 2015 to 2017, and HAdV-B7 (29.17%, 112/384) co-circulated with HAdV-B3 from 2018 to 2019. After NPIs launched, HAdV-B3 and B7 decreased sharply with HAdV-B7 undetected in 2021, while HAdV-C1 became the dominant one and the undetermined were more. CONCLUSIONS: The endemic pattern of HAdV changed in Beijing because of the NPIs launched for COVID-19. Especially, the dominant types changed from HAdV-B to HAdV-C.

Uncertainty and error in SARS-CoV-2 epidemiological parameters inferred from population-level epidemic models.

During the SARS-CoV-2 pandemic, epidemic models have been central to policy-making. Public health responses have been shaped by model-based projections and inferences, especially related to the impact of various non-pharmaceutical interventions. Accompanying this has been increased scrutiny over model performance, model assumptions, and the way that uncertainty is incorporated and presented. Here we consider a population-level model, focusing on how distributions representing host infectiousness and the infection-to-death times are modelled, and particularly on the impact of inferred epidemic characteristics if these distributions are mis-specified. We introduce an SIR-type model with the infected population structured by 'infected age', i.e. the number of days since first being infected, a formulation that enables distributions to be incorporated that are consistent with clinical data. We show that inference based on simpler models without infected age, which implicitly mis-specify these distributions, leads to substantial errors in inferred quantities relevant to policy-making, such as the reproduction number and the impact of interventions. We consider uncertainty quantification via a Bayesian approach, implementing this for both synthetic and real data focusing on UK data in the period 15 Feb-14 Jul 2020, and emphasising circumstances where it is misleading to neglect uncertainty. This manuscript was submitted as part of a theme issue on "Modelling COVID-19 and Preparedness for Future Pandemics".