Non-pharmaceutical Interventions Research Articles

Modelling indoor airborne transmission combining architectural design and people movement using the VIRIS simulator and web app.

A Viral Infection Risk Indoor Simulator (VIRIS) has been developed to quickly assess and compare mitigations for airborne disease spread. This agent-based simulator combines people movement in an indoor space, viral transmission modelling and detailed architectural design, and it is powered by topologicpy, an open-source Python library. VIRIS generates very fast predictions of the viral concentration and the spatiotemporal infection risk for individuals as they move through a given space. The simulator is validated with data from a courtroom superspreader event. A sensitivity study for unknown parameter values is also performed. We compare several non-pharmaceutical interventions (NPIs) issued in UK government guidance, for two indoor settings: a care home and a supermarket. Additionally, we have developed the user-friendly VIRIS web app that allows quick exploration of diverse scenarios of interest and visualisation, allowing policymakers, architects and space managers to easily design or assess infection risk in an indoor space.

Policy impact of the Imperial College COVID-19 Response Team: global perspective and United Kingdom case study.

Mathematical models and advanced analytics play an important role in policy decision making and mobilizing action. The Imperial College Coronavirus Disease 2019 (COVID-19) Response Team (ICCRT) provided continuous, timely and robust epidemiological analyses to inform the policy responses of governments and public health agencies around the world. This study aims to quantify the policy impact of ICCRT outputs, and understand which evidence was considered policy-relevant during the COVID-19 pandemic. We collated all outputs published by the ICCRT between 01-01-2020 and 24-02-2022 and conducted inductive thematic analysis. A systematic search of the Overton database identified policy document references, as an indicator of policy impact. We identified 620 outputs including preprints (16%), reports (29%), journal articles (37%) and news items (18%). More than half (56%) of all reports and preprints were subsequently peer-reviewed and published as a journal article after 202days on average. Reports and preprints were crucial during the COVID-19 pandemic to the timely distribution of important research findings. One-fifth of ICCRT outputs (21%) were available to or considered by United Kingdom government meetings. Policy documents from 41 countries in 26 different languages referenced 43% of ICCRT outputs, with a mean time between publication and reference in the policy document of 256days. We analysed a total of 1746 policy document references. Two-thirds (61%) of journal articles, 39% of preprints, 31% of reports and 16% of news items were referenced in one or more policy documents (these 217 outputs had a mean of 8 policy document references per output). The most frequent themes of the evidence produced by the ICCRT reflected the evidence-need for policy decision making, and evolved accordingly from the pre-vaccination phase [severity, healthcare demand and capacity, and non-pharmaceutical interventions (NPIs)] to the vaccination phase of the epidemic (variants and genomics). The work produced by the ICCRT affected global and domestic policy during the COVID-19 pandemic. The focus of evidence produced by the ICCRT corresponded with changing policy needs over time. The policy impact from ICCRT news items highlights the effectiveness of this unique communication strategy in addition to traditional research outputs, ensuring research informs policy decisions more effectively.

Spatial and temporal transmission dynamics of respiratory syncytial virus in New Zealand before and after the COVID-19 pandemic.

Human respiratory syncytial virus (RSV) is a major cause of acute respiratory infection. In 2020, RSV was eliminated from New Zealand due to non-pharmaceutical interventions (NPI) used to control the spread of SARS-CoV-2. However, in 2021, following a brief quarantine-free travel agreement with Australia, there was a large-scale nationwide outbreak of RSV that led to reported cases more than five-times higher than typical seasonal patterns. We generated 1470 viral genomes of both RSV-A and RSV-B sampled between 2015-2022 from across New Zealand. Using a phylodynamics approach, we used these data to better understand RSV transmission patterns in New Zealand prior to 2020, and how RSV became re-established in the community following the relaxation of COVID-19 restrictions. We found that in 2021, there was a large epidemic of RSV due to an increase in importations, leading to several large genomic clusters of both RSV-A ON1 and RSV-B BA9 genotypes. However, while a number of viral importations were detected, there was also a major reduction in RSV genetic diversity compared to pre-pandemic years. These data reveal the impact of NPI used during the COVID-19 pandemic on other respiratory infections and highlight the important insights that can be gained from viral genomes.

Rising incidence of gonorrhea in Taiwan amid the COVID-19 pandemic: a nationwide surveillance study.

Background The protracted battle against coronavirus disease 2019 (COVID-19) has had a profound impact on various facets of society. The epidemiology of several diseases underwent alterations following the implementation of social restrictive strategies and non-pharmaceutical interventions (NPI). Methods In response to these changes, we conducted a retrospective nationwide surveillance study to investigate the prevalence of sexually transmitted infections during the pandemic. Weekly incidences of gonorrhea, syphilis, human immunodeficiency virus (HIV), and enterovirus were extracted from the national surveillance database. Results Over the period from 2015 to 2022, a sustained increase in gonorrhea notifications was evident (linear trend with a rising slope of 0.24 and an R-squared value of 0.62). When comparing the pre-pandemic period (2017-2019) with the pandemic period (2020-2022), a significant surge in gonorrhea notifications was observed (85 notifications per week pre-pandemic vs 143 notifications during the pandemic, representing a 68% increase, P Conclusions Our study highlights a significant rise in gonorrhea notifications during the pandemic. Despite disruptions to gonorrhea testing and medical services, and the implementation of NPI, there was no significant decrease in the incidence of gonorrhea in Taiwan. Gonorrhea emerged as a critical public health concern during the pandemic.

Local effects of non-pharmaceutical interventions on mitigation of COVID-19 spread through decreased human mobilities in Japan: a prefecture-level mediation analysis

To control the COVID-19 epidemic, the Japanese government and the local governments have repeatedly implemented non-pharmaceutical interventions (NPIs) throughout 2020–2022. Using Bayesian state-space mediation models, we examined the effect of repeated NPIs on infection spread mitigation, mediated by human mobility changes in each prefecture during three epidemic phases: from April 1, 2020 to February 28, 2021; from March 1, 2021 to December 16, 2021; and from December 17, 2021 to December 31, 2022. In the first phase, controlling downtown populations at nighttime was effective in mitigating the infection spread in almost all prefectures. In the second and third phases, the effect was not clear, especially in metropolitan prefectures. Controlling visitors from the central prefectures of metropolitan areas was effective in mitigating infection spread in the surrounding prefectures during all phases. These results suggest that the local spread of infection can be mitigated by focusing on nighttime human mobility control in downtown areas before the epidemic spreads widely and transmission routes become more diverse, and that the geospatial spread of infection can be prevented by controlling the flows of people from large cities to other areas.

Impact of the 100 days mission for vaccines on COVID-19: a mathematical modelling study

The COVID-19 pandemic has underscored the beneficial impact of vaccines. It also highlighted the need for future investments to expedite an equitable vaccine distribution. The 100 Days Mission aims to develop and make available a new vaccine against a future pathogen with pandemic potential within 100 days of that pathogen threat being recognised. We assessed the value of this mission by estimating the impact that it could have had on the COVID-19 pandemic. Using a previously published model of SARS-CoV-2 transmission dynamics fitted to excess mortality during the COVID-19 pandemic, we projected scenarios for three different investment strategies: rapid development and manufacture of a vaccine, increasing manufacturing capacity to eliminate supply constraints, and strengthening health systems to enable faster vaccine roll-outs and global equity. Each scenario was compared against the observed COVID-19 pandemic to estimate the public health and health-economic impacts of each scenario. If countries implemented non-pharmaceutical interventions (NPIs) as they did historically, the 100 Days Mission could have averted an estimated 8·33 million deaths (95% credible interval [CrI] 7·70-8·68) globally, mostly in lower-middle income countries. This corresponds to a monetary saving of US$14·35 trillion (95% CrI 12·96-17·87) based on the value of statistical life-years saved. Investment in manufacturing and health systems further increases deaths averted to 11·01 million (95% CrI 10·60-11·49). Under an alternative scenario whereby NPIs are lifted earlier on the basis of vaccine coverage, the 100 Days Mission alone could have reduced restrictions by 12 600 days (95% CrI 12 300-13 100) globally while still averting 5·76 million deaths (95% CrI 4·91-6·81). Our findings show the value of the 100 Days Mission and how these can be amplified through improvements in manufacturing and health systems equity. However, these investments must be enhanced by prioritising a more equitable global vaccine distribution. Schmidt Science Fellowship in partnership with the Rhodes Trust, WHO, UK Medical Research Council, Coalition for Epidemic Preparedness Innovations.

Non-pharmaceutical interventions to reduce influenza transmission in households: a systematic review and meta-analysis

Influenza pandemic plans often recommend non-pharmaceutical interventions (NPIs) in household settings, including hand hygiene and face masks. We reviewed the evidence supporting the recommendations of these measures to prevent the spread of influenza in households. We performed systematic reviews between 26 May and 30 August 2022 in Medline, PubMed, EMBASE, and CENTRAL to identify evidence for the effectiveness of selected measures recommended by representative national influenza pandemic plans. We prioritized evidence from randomized controlled trials conducted during influenza pandemics and seasonal influenza epidemics. Fixed-effects models were used to estimate the overall effects. Systematic reviews were registered in the OSF registry (https://osf.io/8kyth). We selected 9 NPIs for evidence review. We identified 9 randomized-controlled trials related to hand hygiene and face masks in household settings. 2 studies reported that measures could delay the introduction of influenza virus infections into households. However, we did not identify evidence from randomized controlled trials that indicated a substantial effect of hand hygiene and face masks in preventing the spread of influenza within households. Limited evidence indicated that within-household measures may likely be effective only when implemented before or as soon as possible after symptom onset in an infected case. Improving the evidence base for NPIs in households and elsewhere is a continuing priority. World Health Organization and the Strategic Topic Grants Scheme.

Modelling plausible scenarios for the Omicron SARS-CoV-2 variant from early-stage surveillance

We used a spatially explicit agent-based model of SARS-CoV-2 transmission combined with spatially fine-grained COVID-19 observation data from Public Health Scotland to investigate the initial rise of the Omicron (BA.1) variant of concern. We evaluated plausible scenarios for transmission rate advantage and vaccine immune escape relative to the Delta variant based on the data that would have been available at that time. We also explored possible outcomes of different levels of imposed non-pharmaceutical intervention. The initial results of these scenarios were used to inform the Scottish Government in the early outbreak stages of the Omicron variant.Using the model with parameters fit over the Delta variant epidemic, some initial assumptions about Omicron transmission rate advantage and vaccine escape, and a simple growth rate fitting procedure, we were able to capture the initial outbreak dynamics for Omicron. We found that the modelled dynamics hold up to retrospective scrutiny. The modelled imposition of extra non-pharmaceutical interventions planned by the Scottish Government at the time would likely have little effect in light of the transmission rate advantage held by the Omicron variant and the fact that the planned interventions would have occurred too late in the outbreak’s trajectory. Finally, we found that any assumptions made about the projected distribution of vaccines in the model population had little bearing on the outcome, in terms of outbreak size and timing. Instead, it was the landscape of prior immunity that was most important.

Rethinking residential building design in high-density cities for enhancing pandemic resilience: Balancing importance and practicality

The relationship between the built environment and epidemic transmission is particularly pronounced within the context of lockdown policies and high-density urban areas. Non-pharmaceutical interventions have become increasingly important during and after the COVID-19 pandemic. This study proposes an evaluation index system for pandemic-resilient residential building designs in high-density cities, covering the entire design process including site planning, architecture design, building equipment and management. The system includes 64 design strategies, categorized into 15 sub-categories and 4 categories. Then, we evaluate the preference of each strategy by synthesizing the dimensions of importance and implementation difficulty. A questionnaire survey was conducted among experts who have experience with pandemic-resilient designs in high-density cities. Fuzzy synthetic evaluation analysis was implemented along with the “preference index” concept to identify the most important and practical interventions during the pandemic outbreak. The results indicate that “service and management” is the category that requires priority, followed by “property management,” “common areas” and “building morphology” in sub-categories. Among the design strategies, “waste receptacle,” “publicity and education,” “floor drain and water seal” and “environmental cleaning and disinfection” are the top four recommended strategies. This study provides policymakers and practitioners with effective and easily implementable prevention measures during an outbreak of respiratory tract infections. It also offers specific policy recommendations and application suggestions for new and existing buildings, contributing to creating a safer and healthier living environment

A Retrospective Analysis of Jordan's National COVID-19 Call Center: Operations, Effectiveness, and Lessons Learned.

Contact tracing has been a cornerstone of non-pharmaceutical interventions to control the COVID-19 epidemic, with highly mixed effectiveness internationally. In Jordan, the Ministry of Health (MOH) collaborated with the Jordan Nurses and Midwives Council and the USAID Local Health System Sustainability Project to set up a call center for contact tracing of COVID-19. This study described the operation and assessed the effectiveness of Jordan's COVID-19 call center activities in reaching COVID-19 cases and their contacts. A retrospective observational design was conducted using data from all calls made by the COVID-19 call center cases between November 2020 and April 2022. Data were collected from initial and follow-up calls to PCR-confirmed COVID-19 cases and their contacts. Data on socio-demographics, symptoms, and contact tracing activities were recorded. The study focused on key outcomes, including call success rates, the number of cases and contacts reached, and the role of different detection modes in identifying cases. During the study period, the call center attempted to contact 1,027,911 COVID-19 cases, successfully reaching 802,525 cases (78.1%). Follow-up calls were made to 1,126,334 cases, with a success rate of 74%. The call center appeared particularly valuable during the initial period of the pandemic until it was overwhelmed by the significantly more transmissible Omicron variant of the virus. Two weaknesses were identified: gaps in reaching non-Jordanian citizen cases and difficulty in keeping up with case volume during the Omicron wave of February-March 2022, when reported cases peaked at over 20,000 per day. One-third of all reached cases said that they had been referred for testing through contact tracing. Contact tracing activities led by the MOH were instrumental in identifying new cases, optimizing resource allocation, improving surveillance and data systems, targeting vulnerable population, and supporting mitigation strategies to combat the COVID-19 pandemic in Jordan.

Modelling wellbeing during public health interventions for respiratory epidemics

Throughout the COVID-19 pandemic, the use of non-pharmaceutical interventions (NPIs), including lockdown measures, by governments around the world has been informed by mathematical modelling. Broadly, these models look to gauge how well NPIs control disease transmission. Here we present a model that not only forecasts the effectiveness of NPIs in restricting contacts but also assesses their influence on the mental wellbeing of affected populations. Our model is informed by data from the United Kingdom Time Use Survey, 2014-2015. This survey recorded the time participants spent in different social settings as well as self-reported enjoyment in these settings, allowing us to augment a quantitative model of social contact behaviour with associated wellbeing estimates. We use this model to assess the effectiveness of NPIs aimed at reducing social contacts in different settings and estimate their impact on population-level wellbeing. Our findings indicate that workplace closures represent the most effective intervention for slowing disease spread, while NPIs targeting other contact locations have comparatively limited impacts on transmission. Our model suggests that workplace closures not only effectively reduce infections but also have a relatively modest effect on population wellbeing levels.

Reflective model assessment of adherence to COVID-19 non-pharmaceutical interventions

Abstract Background Non-pharmaceutical interventions (NPIs) decrease COVID-19 transmission. We identified behavioral factors that affected NPI adherence according to Normalization Process Theory (NPT) in medical students, travel seekers, and people with substance use disorder using reflective model measurement, which previously had not been conducted. Public health officials should consider factors that influence adherence to create preventive strategies for COVID-19. Methods In a cross-sectional design, medical students and people with substance use disorders in treatment comprised a probabilistic sample, and travelers and COVID-19 suspected persons comprised a convenience sample. Participants were from Split-Dalmatia County (n = 656) in the Mediterranean and consented to self-administered surveys in 02/2021. Sociodemographic data, locus of control (LoC), and moral behavior were collected. Partial least squares structural equation modeling (PLS-SEM) was used to measure reflective assessment of NPI adherence according to NPT. Results PLS-SEM reflective model assessment provided two-group specific factors in inverse relationships which determined NPI adherence with excellent goodness of fit (χ2=1.292, df = 1; p = 0.297). Significant negative factors covariance estimate (-0.716) revealed an increase in adherence to the first factor, NPIs and internal LoC [0.640], as the second factor, age (≤25) and highest education level (1.362), decreased. LoC was the mechanism by which sex (MLsex=-0.017, SE = 0.007, p < 0.016) and being a student or person with substance use disorder (MLgroup=-0.008, SE = 0.003, p = 0.015) showed indirect effect on NPI adherence. Conclusions Students and people with substance use disorders more adhered to NPIs. Higher-educated younger adults with a tendency toward external LoC facilitated the normalization. Public health interventions could encourage these subgroups to act as promoters to increase NPI adherence in similar settings. Key messages • COVID-19 non-pharmaceutical interventions and psychological factors of students and people with substance abuse disorder influenced adherence. Targeted interventions could promote adherence. • Public health officials should consider that preventive strategies may be more effective in highly educated adults younger than 25 years of age.

Routes of importation and spatial dynamics of SARS-CoV-2 variants during localized interventions in Chile.

Human mobility is strongly associated with the spread of SARS-CoV-2 via air travel on an international scale and with population mixing and the number of people moving between locations on a local scale. However, these conclusions are drawn mostly from observations in the context of the global north where international and domestic connectivity is heavily influenced by the air travel network; scenarios where land-based mobility can also dominate viral spread remain understudied. Furthermore, research on the effects of nonpharmaceutical interventions (NPIs) has mostly focused on national- or regional-scale implementations, leaving gaps in our understanding of the potential benefits of implementing NPIs at higher granularity. Here, we use Chile as a model to explore the role of human mobility on disease spread within the global south; the country implemented a systematic genomic surveillance program and NPIs at a very high spatial granularity. We combine viral genomic data, anonymized human mobility data from mobile phones and official records of international travelers entering the country to characterize the routes of importation of different variants, the relative contributions of airport and land border importations, and the real-time impact of the country's mobility network on the diffusion of SARS-CoV-2. The introduction of variants which are dominant in neighboring countries (and not detected through airport genomic surveillance) is predicted by land border crossings and not by air travelers, and the strength of connectivity between comunas (Chile's lowest administrative divisions) predicts the time of arrival of imported lineages to new locations. A higher stringency of local NPIs was also associated with fewer domestic viral importations. Our analysis sheds light on the drivers of emerging respiratory infectious disease spread outside of air travel and on the consequences of disrupting regular movement patterns at lower spatial scales.

The circulating characteristics of common respiratory pathogens in Ningbo, China, both before and following the cessation of COVID-19 containment measures

To assess the circulating characteristics of common respiratory pathogens following the complete relaxation of non-pharmaceutical interventions (NPIs) and the cessation of the dynamic zero-COVID policy. The retrospective analysis was conducted from 14,412 patients with acute respiratory infections (ARIs) from January 24, 2020, to December 31, 2023, including Influenza A virus (IFV-A), Influenza B virus (IFV-B), Respiratory Syncytial Virus (RSV), Human Rhinovirus (HRV), Human Parainfluenza Virus (HPIV), Human Metapneumovirus (HMPV), Human Coronavirus (HCoV), Human Bocavirus (HBoV), Human Adenovirus (HAdV), and Mycoplasma pneumoniae (MP). Compared with 2020–2022, Joinpoint analysis indicated a monthly increase in overall pathogen activity in 2023, rising from an average of 43.05% to an average of 68.46%. The positive rates of IFV-A, IFV-B, HMPV, HPIV, HCoV, and MP increased, while those of HRV and RSV decreased, and no differences in HAdV and HBoV. The outbreak of IFV-A and MP was observed, the positive rate of MP has surpassed pre-COVID-19 pandemic levels and the spread of RSV was interrupted by IFV-A. Infants and toddlers were primarily infected by HRV and RSV, Children and adolescents exhibited a higher prevalence of infections with MP, IFV-A, and HRV, whereas Adults and the elderly were primarily infected by IFV-A. The incidence of co-infections rose from 4.25 to 13.73%. Restricted cubic spline models showed that the susceptible age ranges for multiple pathogens expanded. These changes serve as a reminder to stay alert in the future and offer clinicians a useful guide for diagnosing and treating.

Interactive Simulation of Nonpharmaceutical Interventions of Airborne Disease Transmission in Office Settings

The COVID-19 pandemic has caused major disruptions to workplace safety and productivity. A browser-based interactive disease transmission simulation was developed to enable managers and individuals (agents) to optimize safe office work activities during pandemic conditions. The application provides a user interface to evaluate the impact of non-pharmaceutical interventions (NPIs) policies on airborne disease exposure based on agents’ meeting patterns and room properties. Exposure is empirically calibrated using CO2 as a proxy for viral aerosol dispersion. For the building studied, the major findings are that the cubicles during low occupancy produce unexpectedly high exposure, upgrading meetings to larger rooms reduces total average exposure by 44%, and when all meetings are conducted in large rooms, a 79% exposure reduction is realized.

Clusters of African countries based on the social contacts and associated socioeconomic indicators relevant to the spread of the epidemic

IntroductionIt is well known that social contact patterns differ from country to country. This variation coincides with significant socioeconomic heterogeneity that complicates the design of effective nonpharmaceutical interventions. This study examined how socioeconomic heterogeneity in selected African countries might be factored in to explain better patterns of social contact mix between countries.MethodsWe used a standardized contact matrix for 32 African countries, estimated in (Prem et al. in PLoS Comput Biol 17(7):e1009098, 2021). We scaled the matrices using an epidemic model from (Röst et al. in Viruses 12(7):708, 2020). We also analyzed aggregated data from the World Bank country website. The data includes 28 variables; social, economic, environmental, institutional, governance, health and well-being, education, gender inequality, and other development-related indicators that describe countries. Principal component analysis was used to visualize socioeconomic similarities between countries and identify the indicators for maximum variation. The (2D)2PCA\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$(2D)^{2} PCA$\\end{document} approach was used to reduce the dimension of synthetic contact matrices for each country to avoid the dimensionality curse. Then, hierarchical aggregate clustering was used to identify groups of countries with similar social patterns, taking into account the country’s socioeconomic performance.ResultsOur model yielded four meaningful clusters, each with a few distinguishing features. Social contacts varied between groups, but were generally similar within each set. The socioeconomic performance of the country influenced the clusters.ConclusionsOur results suggest that integrating socioeconomic factors into social contacts can better explain infectious disease transmission dynamics and that similar interventions can be implemented in countries within the cluster

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.

The Determination of the Rapid and Effective Activity of an Air Sanitizer against Aerosolized Bacteria Using a Room-Sized Aerobiology Chamber.

Air sanitization is an important non-pharmaceutical intervention for mitigating the risk of indoor pathogen spreading. A dipropylene glycol-containing air sanitizer was tested against aerosolized Staphylococcus aureus and Klebsiella pneumoniae. The bacteria, suspended in a soil load, were aerosolized using a six-jet Collison nebulizer with pressurized air. The 25-m3 (~900 ft3) aerobiology chamber was maintained at 22 ± 2 °C and 50 ± 5% relative humidity per the U.S. Environmental Protection Agency's 2012 Guidelines on air sanitizers. An initial 2-min air sample was collected from the chamber using a slit-to-agar sampler containing 150-mm Petri plates, with Trypticase soy agar (TSA) containing neutralizers to quench the microbicidal activity of the air sanitizer, to determine the initial bacterial challenge in the air. The air sanitizer was sprayed into the chamber from pressurized cans. Additional air samples were collected from the chamber over 10 min to detect surviving bacteria. The TSA plates were then incubated aerobically at 36 ± 1 °C for 90 ± 4 h and scored for bacterial colony-forming units. A 30-s spray of the air sanitizer reduced infectious S. aureus and K. pneumoniae titers by 3.0 log10 (99.9%) in 3.2 ± 0.3 min and 1.2 ± 0.0 min, respectively. Based on these findings, the EPA granted registration of the air sanitizer as the first product of its kind for indoor air sanitization.

Impact of pharmaceutical and non-pharmaceutical interventions on COVID-19 in Tunisia

BackgroundIn COVID-19 management, a variety of pharmaceutical interventions (PI) and non- pharmaceutical interventions (NPI) were adopted to limit the spread of the disease and its associated deaths. We aimed to evaluate the impact of PI and NPI on risks of COVID-19 transmission and deaths.MethodWe collected aggregate data from March 2nd, 2020, to December 1, 2022 from the Tunisian Ministry of Health's website and OurWorldInData.org site. NPI Periods (NPIP: March 2020 to March 2021) and PI Periods (PIP) were distributed to NPIP1, 2, 3 and 4 and to PIP1, 2, 3 and 4, respectively. We calculated the Relative Risks (RR) and 95% Confidence Intervals (CI) by comparing the subsequent period with previous one.ResultsThe risk of SARS-CoV-2 transmission increased progressively from the zero cases period (NPIP2) to the mitigate strategy period (NPIP3) (RR = 14.0; 95% CI: 12.4–15.8) and to the stop-and-go epidemic control period (NPIP4) (RR = 23.1 (95% CI: 22.4–23.9). It was stabilized in the targeted vaccination period (PIP1) (RR = 1.08, 95% CI: 1.07–1.08) and reduced during the mass vaccination period (PIP2) (RR: 0.50, 95% CI: 0.50–0.51). SARS-CoV-2 transmission, increased during PIP3 concomitant with the Omicron wave (RR = 2.65, 95% CI: 2.64–2.67). It remained at a low level in PIP4 (RR = 0.18; 95% CI: 0.18–0.18).Compared to NPIP2, NPIP3 and NPIP4 were associated with a higher risk of COVID-19 mortality (RR = 3.337; 95% CI: 1.797–6.195) and (RR = 72.63 (95% CI: 54.01–97.68), respectively. Since the start of the immunization program, the risk of COVID-19 death has consistently decreased. In comparison to each previous period, the risk transitioned in PIP1 to RR = 0.91; 95% CI: 0.88–0.93, then to RR = 0.85; 95% CI: 0.83–0.88 in PIP2, to RR = 0.47; 95% CI: 0.45–0.50 in PIP3, and to RR = 0.19; 95% CI: 0.18–0.24 during PIP4.ConclusionIn terms of lowering the risk of transmission and mortality, the NP strategy at the beginning of the epidemic outperformed the IP strategy during the outbreak.

Cycles of susceptibility: Immunity debt explains altered infectious disease dynamics post -pandemic.

The concept of immunity debt is a phenomenon resulting from the suppression of endemic pathogens during the COVID-19 pandemic due to non-pharmaceutical interventions (NPIs). The reduced circulation of various pathogens during the pandemic, particularly respiratory syncytial virus (RSV), altered typical infectious disease dynamics by reducing levels of population immunity usually acquired through exposure to infection. This concept is demonstrated through post-pandemic resurgence of diseases such as RSV and Group A Streptococcus, and highlights the interplay between reduced pathogen exposure and increased susceptibility in populations. The complexities and non-linear dynamics of seasonal transmission are observed in differences in pathogen resurgence across regions. These issues highlight the importance of comprehensive disease surveillance and public health strategies in mitigating these long-term epidemiological impacts.