Estimating the Effectiveness of Non-Pharmaceutical Interventions on COVID-19 Control in Korea

Determining the best mathematical model for implementation of non-pharmaceutical interventions

At the onset of the SARS-CoV-2 pandemic in early 2020, only non-pharmaceutical interventions (NPIs) were available to stem the spread of the infection. Much of the early interventions in the US were applied at a state level, with varying levels of strictness and compliance. While NPIs clearly slowed the rate of transmission, it is not clear how these changes are best incorporated into epidemiological models. In order to characterize the effects of early preventative measures, we use a Susceptible-Exposed-Infected-Recovered (SEIR) model and cumulative case counts from US states to analyze the effect of lockdown measures. We test four transition models to simulate the change in transmission rate: instantaneous, linear, exponential, and logarithmic. We find that of the four models examined here, the exponential transition best represents the change in the transmission rate due to implementation of NPIs in the most states, followed by the logistic transition model. The instantaneous and linear models generally lead to poor fits and are the best transition models for the fewest states.

Effect of individual preventive practices on COVID-19 infection: an analysis of big data collected at PCR testing centers in Hiroshima, Japan

BACKGROUND

By May 7, 2023, COVID-19 had significantly impacted Japan, with 33,728,909 infections and 74,663 deaths reported. Hiroshima Prefecture alone recorded 816,354 cases and 1,373 deaths. The World Health Organization emphasized the importance of non-pharmaceutical interventions (NPIs) for preventing infectious disease transmission. Individual NPIs, such as hand hygiene, mask wearing, and avoiding crowded places, comprise simple everyday measures that individuals can personally undertake to protect themselves and others from contracting and transmitting respiratory infections. Japan's Cabinet Secretariat also recommended these measures. Previous studies investigated the effectiveness of NPIs but often used relatively short data-collection periods. Starting in May 2020, Hiroshima Prefecture adopted a unique COVID-19 public health surveillance policy that used standardized data-collection forms. The present analysis examines the association between individual NPIs and COVID-19 infections.

METHODS

Data were collected at 14 PCR centers from April 1, 2021, to August 3, 2022 in Hiroshima Prefecture. Participants filled out the J-SPEED-style COVID-19 form, which included items on demographic information, job type, symptoms, and NPIs. The data were analyzed for demographic information, NPI compliance rates, infection rates in relation to NPI adoption, and adjusted risk ratios, which were obtained using a multivariate log-binomial regression model.

RESULTS

A total of 1,125,188 tested cases from 4th to 7th waves were analyzed. Among the study population, the infection rate increased through the various waves, with the highest rate (8.3%) seen in the 7th wave. Adults aged 40-49 were most commonly tested, while those aged 60-69 had the lowest infection rates. Wearing masks/washing hands was the most commonly followed NPI. Compliance with NPIs decreased through the waves. Individuals adhering to NPIs had lower infection rates. The number of preventive measures adopted was correlated with a reduced infection risk.

CONCLUSION

This analysis provides evidence to guide COVID-19 prevention policies. Simultaneous adherence to multiple NPIs proved more effective in preventing COVID-19. Despite changes in viral strains and the number of infected cases, hand washing/mask wearing, refraining from travel, and refraining from dining out significantly associated with a reduction of COVID-19 infection. Our findings are likely to be applicable in future infectious disease outbreaks.

Persuasive Effects of Crisis Communication during Public Health Emergency Outbreaks in China

Major global public health emergencies face unprecedented challenges, such as an infodemic and scientific disputes, and governments especially need to implement fast and effective crisis communication. Firstly, this paper takes the Elaboration Likelihood Model as a framework and constructs a crisis communication persuasion effect evaluation method with emotion analysis. Secondly, this paper takes the crisis communication at the beginning of the COVID-19 outbreak in China as an example and examines the persuasive effects of the peripheral route, represented by medical experts, and the central route, represented by mainstream media. This study finds that the peripheral route of persuasive communication can quickly establish communication trust and quickly change the public's peripheral attitude, but the persuasive effect is unstable. The central route of persuasive communication demonstrates a significantly positive, stable, and anti-interference persuasive effect. Dual-subject persuasion is an important strategy for controlling an outbreak by rapidly establishing communication trust, combating an infodemic, boosting public confidence, and popularizing medical knowledge. This study evaluates the persuasive effects of crisis communication in the early stages of the COVID-19 outbreak in China, hoping to provide valuable practical references for crisis communication during the outbreak in future global public health emergencies.

Trends in Nationally Notifiable Infectious Diseases in Humans and Animals during COVID-19 Pandemic, South Korea

We investigated trends in notifiable infectious diseases in both humans and animals during the COVID-19 pandemic in South Korea and compared those data against expected trends had nonpharmaceutical interventions (NPIs) not been implemented. We found that human respiratory infectious diseases other than COVID-19 decreased by an average of 54.7% after NPIs were introduced. On the basis of that trend, we estimated that annual medical expenses associated with respiratory infections other than COVID-19 also decreased by 3.8% in 2020 and 18.9% in 2021. However, human gastrointestinal infectious diseases and livestock diseases exhibited similar or even higher incidence rates after NPIs were instituted. Our investigation revealed that the preventive effect of NPIs varied among diseases and that NPIs might have had limited effectiveness in reducing the spread of certain types of infectious diseases. These findings suggest the need for future, novel public health interventions to compensate for such limitations.

Trends in emergency department visits for emergency care-sensitive conditions before and during the COVID-19 pandemic: a nationwide study in Korea, 2019-2021

OBJECTIVE

Emergency care systems worldwide have been significantly affected by the COVID-19 pandemic. This study investigated the trend of emergency department (ED) visits for emergency care-sensitive conditions (ECSCs) in Korea before and during the pandemic.

METHODS

We performed a longitudinal study using the national ED database in Korea from January 2019 to December 2021. We calculated the number and incidence rate of visits for ECSCs per 100,000 ED visits, and the incidence rate ratio of 2021 relative to the value in 2019. The selected ECSCs were intracranial injury, ischemic heart disease, stroke, and cardiac arrest.

RESULTS

The number of ED visits for all causes decreased by about 23% during the pandemic. The number of ED visits for intracranial injuries decreased from 166,695 in 2019 to 133,226 in 2020 and then increased to 145,165 in 2021. The number of ED visits for ischemic heart disease and stroke decreased in 2020 but increased to 2019 levels in 2021. In contrast, the number of ED visits for cardiac arrest increased from 23,903 in 2019 to 24,344 in 2020 and to 27,027 in 2021. The incidence rate and incidence rate ratio of these four ECSCs increased from 2019 to 2021, suggesting increasing relative proportions of ECSCs in total ED visits.

CONCLUSION

During the COVID-19 pandemic, the number of cardiac arrests seen in the EDs increased, but that of other ECSCs decreased. The decrease in ED visits for ECSCs was not as pronounced as the decrease in ED visits for all causes during the pandemic. Further studies are needed to determine clinical outcomes in patients with ECSC during the pandemic.

Nationwide Trends in Non-COVID-19 Infectious Disease Laboratory Tests in the Era of the COVID-19 Pandemic in Korea

The coronavirus disease 2019 pandemic has brought significant changes to infectious disease management globally. This study explored changes in clinical microbiological testing trends and their implications for infectious disease incidence and medical utilization during the pandemic. We collected nationwide claims for monthly clinical microbiology tests from January 2018 to March 2022 using the National Health Insurance Service database. Seasonal autoregressive integrated moving average models were employed to make predictions for each disease based on the baseline period (January 2018 to January 2020). The results showed a significant decrease in general bacterial and fungal cultures, respiratory infectious disease-related, and inflammatory markers, while the representatives of tests for vector-borne diseases, healthcare-associated infections, and chronic viral infections remained stable. The study highlights the potential of clinical microbiological testing trends as an additional surveillance tool and offers implications for future infectious disease management and surveillance strategies in pandemic settings.

Nonpharmaceutical interventions reduce the incidence and mortality of COVID-19: A study based on the survey from the International COVID-19 Research Network (ICRN)

The recently emerged novel coronavirus, "severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)," caused a highly contagious disease called coronavirus disease 2019 (COVID-19). It has severely damaged the world's most developed countries and has turned into a major threat for low- and middle-income countries. Since its emergence in late 2019, medical interventions have been substantial, and most countries relied on public health measures collectively known as nonpharmaceutical interventions (NPIs). We aimed to centralize the accumulative knowledge of NPIs against COVID-19 for each country under one worldwide consortium. International COVID-19 Research Network collaborators developed a cross-sectional online survey to assess the implications of NPIs and sanitary supply on the incidence and mortality of COVID-19. The survey was conducted between January 1 and February 1, 2021, and participants from 92 countries/territories completed it. The association between NPIs, sanitation supplies, and incidence and mortality were examined by multivariate regression, with the log-transformed value of population as an offset value. The majority of countries/territories applied several preventive strategies, including social distancing (100.0%), quarantine (100.0%), isolation (98.9%), and school closure (97.8%). Individual-level preventive measures such as personal hygiene (100.0%) and wearing facial masks (94.6% at hospitals; 93.5% at mass transportation; 91.3% in mass gathering facilities) were also frequently applied. Quarantine at a designated place was negatively associated with incidence and mortality compared to home quarantine. Isolation at a designated place was also associated with reduced mortality compared to home isolation. Recommendations to use sanitizer for personal hygiene reduced incidence compared to the recommendation to use soap. Deprivation of masks was associated with increased incidence. Higher incidence and mortality were found in countries/territories with higher economic levels. Mask deprivation was pervasive regardless of economic level. NPIs against COVID-19 such as using sanitizer, quarantine, and isolation can decrease the incidence and mortality of COVID-19.

Nonpharmaceutical interventions reduce the incidence and mortality of COVID‐19: A study based on the survey from the International COVID‐19 Research Network (ICRN)

The recently emerged novel coronavirus, “severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2),” caused a highly contagious disease called coronavirus disease 2019 (COVID‐19). It has severely damaged the world's most developed countries and has turned into a major threat for low‐ and middle‐income countries. Since its emergence in late 2019, medical interventions have been substantial, and most countries relied on public health measures collectively known as nonpharmaceutical interventions (NPIs). We aimed to centralize the accumulative knowledge of NPIs against COVID‐19 for each country under one worldwide consortium. International COVID‐19 Research Network collaborators developed a cross‐sectional online survey to assess the implications of NPIs and sanitary supply on the incidence and mortality of COVID‐19. The survey was conducted between January 1 and February 1, 2021, and participants from 92 countries/territories completed it. The association between NPIs, sanitation supplies, and incidence and mortality were examined by multivariate regression, with the log‐transformed value of population as an offset value. The majority of countries/territories applied several preventive strategies, including social distancing (100.0%), quarantine (100.0%), isolation (98.9%), and school closure (97.8%). Individual‐level preventive measures such as personal hygiene (100.0%) and wearing facial masks (94.6% at hospitals; 93.5% at mass transportation; 91.3% in mass gathering facilities) were also frequently applied. Quarantine at a designated place was negatively associated with incidence and mortality compared to home quarantine. Isolation at a designated place was also associated with reduced mortality compared to home isolation. Recommendations to use sanitizer for personal hygiene reduced incidence compared to the recommendation to use soap. Deprivation of masks was associated with increased incidence. Higher incidence and mortality were found in countries/territories with higher economic levels. Mask deprivation was pervasive regardless of economic level. NPIs against COVID‐19 such as using sanitizer, quarantine, and isolation can decrease the incidence and mortality of COVID‐19.

Mathematical Modeling of COVID-19 Transmission and Intervention in South Korea: A Review of Literature

South Korea implemented interventions to curb the spread of the novel coronavirus disease 2019 (COVID-19) pandemic with discovery of the first case in early 2020. Mathematical modeling designed to reflect the dynamics of disease transmission has been shown to be an important tool for responding to COVID-19. This study aimed to review publications on the structure, method, and role of mathematical models focusing on COVID-19 transmission dynamics in Korea. In total, 42 papers published between August 7, 2020 and August 21, 2022 were studied and reviewed. This study highlights the construction and utilization of mathematical models to help craft strategies for predicting the course of an epidemic and evaluating the effectiveness of control strategies. Despite the limitations caused by a lack of available epidemiological and surveillance data, modeling studies could contribute to providing scientific evidence for policymaking by simulating various scenarios.

COVID-19 Outbreak in Daegu City, Korea and Response to COVID-19: How Have We Dealt and What Are the Lessons?

The first coronavirus disease 2019 (COVID-19) outbreak in Daegu city was overcome by efforts, including; 1) prompt isolation and quarantine action by local government with cooperative help from expert groups and the central government, 2) high-intensity social distancing and active cooperation of citizens, 3) admission of asymptomatic and mild patients in 'residential treatment centers', and 4) use of a telephone scoring system for the allocation of patients, with a mortality rate of 2.5%. A continuous suppression policy with test, tracing, and treatment (3 Ts) was implemented as an active response to the initial outbreaks in Korea. With the introduction of vaccines and therapeutic agents, the COVID-19 crisis had improved. Recently, the omicron variant was responsible for most domestic outbreaks, albeit with a low mortality rate (0.1%). Since the omicron outbreak, a damage mitigation policy has been implemented, focusing on protecting vulnerable groups. In the future, preparation including below are needed; 1) improving the national public health emergency response system, 2) strengthening the crisis response capacity of local governments, 3) cooperation between public healthcare and private healthcare, and 4) establishing a resilient medical response system.

Efficiency of Malaysian states in managing the COVID-19 outbreak in 2020 and 2021

INTRODUCTION

Many developing countries have drastically imbalanced health systems in different regions. The COVID-19 outbreak posed a further challenge as hospital structures, equipped with doctors, critical care units and respirators, were not available to a sufficient extent in all regions.

OBJECTIVE

This study is a descriptive study on the efficiency of Malaysian states in facing the COVID-19 outbreak.

METHODOLOGY

The efficiency of all Malaysian states was measured using Data Envelopment Analysis in which each state's Score of COVID Index (SCI) was quantified. The SCI of these states were then further compared between the year 2020 and 2021. A greater disparity would indicate a decline in the performance of a state over time, where nearly all the states in Malaysia experienced an increase in the score of COVID Index (SCI).

RESULT

This study found that the central region was the most affected, since all the three states in the region (Selangor, Federal Territory of Kuala Lumpur, and Federal Territory of Putrajaya) showed a situation of inadequacy (SCI: >0.75) due to the COVID-19 outbreak.

CONCLUSION

The ranking of Malaysia's states according to their vulnerability to an outbreak of COVID-19 is vitally significant for the purposes of assisting the government and policymakers in planning their responses to the outbreak and ensuring that resources are distributed appropriately.

Congregational Worshiping and Implementation of the COVID-19 Preventive Behavioral Measures During the Re-opening Phase of Worship Places Among Indonesian Muslims

This research aimed at exploring the congregational form of worshiping and the preventative behaviors against COVID-19 among Indonesian Muslims during the re-opening phase of worship places. One thousand and ninety-seven (1097) participants who were a part of one of the largest Indonesian socio-religious organizations (Muhammadiyah) were included in the study. This study found most of the respondents to have performed tarawih prayers (66.7%) and Eid prayers (67.4%) at home during the pandemic. Furthermore, some Muslim worshipers did not observe COVID-19 preventive behavioral measures during the congregational prayers, and the attended mosques had inadequate facilitation for COVID-19 prevention. Neverthless, mosques are important settings for health promotion programs, whose religious leaders can be partners in delivering health related messages to their attending members.

Variability and strictness in COVID-19 government response: A macro-regional assessment

We examine the effectiveness of non-pharmaceutical government interventions (NPIs) against COVID-19. In particular, we focus on the impact of strictness and variability in government interventions on the reproduction rate (Rt) and the number of new deaths (per million of inhabitants) in five different world regions (G7, G20, EU28, Central America and Asia). In line with existing evidence, we observe that more stringent and frequent NPIs contributed to slow down contagion. Unfortunately, no benefits in terms of mortality are found. In fact, with few exceptions, both strictness and variability in NPIs are associated with a rise in the number of new deaths. This evidence is observed to be stronger among advanced economies and over the second pandemic wave. Take together, our research findings advocate early and decisive implementation of NPIs, but gradual and staggered relaxation of NPIs when the pandemic appears to recede.

Changes in Urban Walking Before and During the COVID-19 Pandemic in a Metropolitan City of South Korea

This study aimed to assess how social distancing measures impacted the choice of walking as a transportation mode, environmental preferences for walking, and walking practice among urban residents in Seoul, the capital city of South Korea. Data was collected through an online survey from September 21 to 28, 2020, when the second level of social distancing measures was implemented; 2,112 participants aged 19 years or older were included in the analysis. During the coronavirus disease 2019 (COVID-19) pandemic, the choice of walking as a means of transportation increased by 10.1 percent points, while that of public transportation decreased by 16.9 percent points. Environmental preferences for walking were more than moderate in neighborhood public open spaces, neighborhood streets, and riverside trails. Despite the increased choice of walking as a means of transportation during the COVID-19 pandemic, walking practices by purpose decreased significantly. In particular, the decrease in walking practice was more pronounced in utilitarian purpose than in leisure purpose. The present study suggests that social distancing measures have an overall effect on environmental preferences, travel attitudes, and behaviors related walking among urban residents in the metropolitan city. To break the physical inactivity habits established during the pandemic, guidelines for promoting walking should be developed, with a focus on increasing the frequency of walking practice. In the post-COVID-19 era, urban and transportation planning in metropolitan cities need to adjust their focus on the development of neighborhood assets related to walking as a health promotion strategy for the upcoming pandemic.

Effectiveness of non-pharmaceutical public health interventions against COVID-19: A systematic review and meta-analysis

Non-Pharmaceutical Public Health Interventions (NPHIs) have been used by different countries to control the spread of the COVID-19. Despite available evidence regarding the effectiveness of NPHSs, there is still no consensus about how policymakers can trust these results. Studies on the effectiveness of NPHSs are single studies conducted in specific communities. Therefore, they cannot individually prove if these interventions have been effective in reducing the spread of the infection and its adverse health outcomes. In this systematic review, we aimed to examine the effects of NPHIs on the COVID-19 case growth rate, death growth rate, Intensive Care Unit (ICU) admission, and reproduction number in countries, where NPHIs have been implemented. We searched relevant electronic databases, including Medline (via PubMed), Scopus, CINAHL, Web of Science, etc. from late December 2019 to February 1, 2021. The key terms were primarily drawn from Medical Subject Heading (MeSh and Emtree), literature review, and opinions of experts. Peer-reviewed quasi-experimental studies were included in the review. The PROSPERO registration number is CRD42020186855. Interventions were NPHIs categorized as lockdown, stay-at-home orders, social distancing, and other interventions (mask-wearing, contact tracing, and school closure). We used PRISMA 2020 guidance for abstracting the data and used Cochrane Effective Practice and Organization of Practice (EPOC) Risk of Bias Tool for quality appraisal of the studies. Hartung-Knapp-Sidik-Jonkman random-effects model was performed. Main outcomes included COVID-19 case growth rate (percentage daily changes), COVID-19 mortality growth rate (percentage daily changes), COVID-19 ICU admission (percentage daily changes), and COVID-19 reproduction number changes. Our search strategies in major databases yielded 12,523 results, which decreased to 7,540 articles after eliminating duplicates. Finally, 35 articles qualified to be included in the systematic review among which 23 studies were included in the meta-analysis. Although studies were from both low-income and high-income countries, the majority of them were from the United States (13 studies) and China (five studies). Results of the meta-analysis showed that adoption of NPHIs has resulted in a 4.68% (95% CI, -6.94 to -2.78) decrease in daily case growth rates, 4.8% (95 CI, -8.34 to -1.40) decrease in daily death growth rates, 1.90 (95% CI, -2.23 to -1.58) decrease in the COVID-19 reproduction number, and 16.5% (95% CI, -19.68 to -13.32) decrease in COVID-19 daily ICU admission. A few studies showed that, early enforcement of lockdown, when the incidence rate is not high, contributed to a shorter duration of lockdown and a lower increase of the case growth rate in the post-lockdown era. The majority of NPHIs had positive effects on restraining the COVID-19 spread. With the problems that remain regarding universal access to vaccines and their effectiveness and considering the drastic impact of the nationwide lockdown and other harsh restrictions on the economy and people's life, such interventions should be mitigated by adopting other NPHIs such as mass mask-wearing, patient/suspected case isolation strategies, and contact tracing. Studies need to address the impact of NPHIs on the population's other health problems than COVID-19.

"Salus Populi Suprema Lex": Considerations on the Initial Response of the United Kingdom to the SARS-CoV-2 Pandemic

In several countries worldwide, the initial response to coronavirus disease 2019 (COVID-19) has been heavily criticized by general public, media, and healthcare professionals, as well as being an acrimonious topic in the political debate. The present article elaborates on some aspects of the United Kingdom (UK) primary reaction to SARS-CoV-2 pandemic; specifically, from February to July 2020. The fact that the UK showed the highest mortality rate in Western Europe following the first wave of COVID-19 certainly has many contributing causes; each deserves an accurate analysis. We focused on three specific points that have been insofar not fully discussed in the UK and not very well known outside the British border: clinical governance, access to hospital care or intensive care unit, and implementation of non-pharmaceutical interventions. The considerations herein presented on these fundamental matters will likely contribute to a wider and positive discussion on public health, in the context of an unprecedented crisis.

Reconstructing a COVID-19 outbreak within a religious group using social network analysis simulation in Korea

OBJECTIVES

We reconstructed a coronavirus disease 2019 (COVID-19) outbreak to examine how a large cluster at a church setting spread before being detected and estimate the potential effectiveness of complying with mask-wearing guidelines recommended by the government.

METHODS

A mathematical model with a social network analysis (SNA) approach was used to simulate a COVID-19 outbreak. A discrete-time stochastic simulation model was used to simulate the spread of COVID-19 within the Sarang Jeil church. A counterfactual experiment using a calibrated baseline model was conducted to examine the potential benefits of complying with a mask-wearing policy.

RESULTS

Simulations estimated a mask-wearing ratio of 67% at the time of the outbreak, which yielded 953.8 (95% confidence interval [CI], 937.3 to 970.4) cases and was most consistent with the confirmed data. The counterfactual experiment with 95% mask-wearing estimated an average of 45.6 (95% CI, 43.4 to 47.9) cases with a standard deviation of 20.1. The result indicated that if the church followed government mask-wearing guidelines properly, the outbreak might have been one-twentieth the size.

CONCLUSIONS

SNA is an effective tool for monitoring and controlling outbreaks of COVID-19 and other infectious diseases. Although our results are based on simulations and are thus limited, the precautionary implications of social distancing and mask-wearing are still relevant. Since person-to-person contacts and interactions are unavoidable in social and economic life, it may be beneficial to develop precise measures and guidelines for particular organizations or places that are susceptible to cluster outbreaks.

Motivation and Intention Toward Physical Activity During the COVID-19 Pandemic: Perspectives From Integrated Model of Self-Determination and Planned Behavior Theories

Background: In attempts to hinder the spread of the Coronavirus disease 2019 (COVID-19), many countries have continued distancing, isolation, and quarantine measures, which has led to limited opportunity of physical activity. This study provides empirical support for a motivational process behind physical activity during the COVID-19 pandemic by testing the influence of psychosocial variables derived from the integrated model of self-determination theory (SDT) and the theory of planned behavior (TPB). Methods: A cross-sectional survey was conducted among Korean adults (N = 248). Participants completed the measures of SDT and TPB constructs modified to reflect their participation in physical activity during the COVID-19 pandemic. A sample size of 243 participants was employed, and the integrated model was tested using serial multiple mediation analysis to check the hypothesized relationships. Results: Findings indicated that in the COVID-19 context, the satisfaction of basic psychological needs positively predicts the level of self-determined motivations for physical activity, which is partially related to the level of social cognitive beliefs and intentions. The findings also demonstrated that attitude toward physical activity during COVID-19 was a major variable explaining the serial multiple relationships between the SDT and TPB constructs. The potential influence of demographics (gender, age, marital status, and past physical activity) was controlled as a covariate, and no significant effects were identified. Conclusion: The current study identified the psychosocial mechanisms of intention of South Koreans' physical activity during the COVID-19 pandemic, which could be used as an empirical basis for the development of interventions to maintain or strengthen physical activity in unprecedented situations.

Grappling with COVID-19 by imposing and lifting non-pharmaceutical interventions in Sri Lanka: A modeling perspective

The imposition and lifting of non-pharmaceutical interventions (NPIs) to avert the COVID-19 pandemic have gained popularity worldwide and will continue to be enforced until herd immunity is achieved. We developed a linear regression model to ascertain the nexus between the time-varying reproduction number averaged over a time window of six days (R_ts) and seven NPIs: contact tracing, quarantine efforts, social distancing and health checks, hand hygiene, wearing of facemasks, lockdown and isolation, and health-related supports. Our analysis suggests that the second wave that emerged in Sri Lanka in early October 2020 continued despite numerous NPIs.

The model indicates that the most effective single NPI was lockdown and isolation. Conversely, the least effective individual NPIs were hand hygiene and wearing of facemasks. The model also demonstrates that to mitigate the second wave to a satisfactory level (R_ts<1), the best single NPI was the contact tracing with stringent imposition (% of improvement of R_ts was 69.43 against the base case). By contrast, the best combination of two NPIs was the lockdown & isolation with health-related supports (% of improvement was 31.92 against the base case). As such, many health authorities worldwide can use this model to successfully strategize the imposition and lifting of NPIs for averting the COVID-19 pandemic.

Associations Between Compliance With Non-pharmaceutical Interventions and Social-distancing Policies in Korea During the COVID-19 Pandemic

OBJECTIVES

This study explored changes in individuals' behavior in response to social distancing (SD) levels and the "no gatherings of more than 5 people" (NGM5) rule in Korea during the coronavirus disease 2019 (COVID-19) pandemic.

METHODS

Using survey data from the COVID-19 Behavior Tracker, exploratory factor analysis extracted 3 preventive factors: maintenance of personal hygiene, avoiding going out, and avoiding meeting people. Each factor was used as a dependent variable. The chi-square test was used to compare differences in distributions between categorical variables, while binary logistic regression was performed to identify factors associated with high compliance with measures to prevent transmission.

RESULTS

In men, all 3 factors were significantly associated with lower compliance. Younger age groups were associated with lower compliance with maintenance of personal hygiene and avoiding meeting people. Employment status was significantly associated with avoiding going out and avoiding meeting people. Residence in the capital area was significantly associated with higher compliance with personal hygiene and avoiding venturing out. Increasing SD levels were associated with personal hygiene, avoiding going out, and avoiding meeting people. The NGM5 policy was not significantly associated with compliance.

CONCLUSIONS

SD levels, gender, age, employment status, and region had explanatory power for compliance with non-pharmaceutical interventions (NPIs). Strengthening social campaigns to inspire voluntary compliance with NPIs, especially focused on men, younger people, full-time workers, and residents of the capital area is recommended. Simultaneously, efforts need to be made to segment SD measures into substrategies with detailed guidance at each level.

Modeling the effectiveness of social distancing interventions on the epidemic curve of coronavirus disease in Ethiopia

SARS-CoV-2 infections are now spreading across the world. Different measures were used by governments around the world to combat the spread of COVID-19. The efficacy of social distancing approaches in reducing the spread of COVID-19 in Ethiopia was investigated using geospatial technologies and the CHIME model. The COVID-19 response was predicted, measured, and compared after 25%, 75%, and 95% social distancing interventions in Ethiopia. Social distancing strategies flatten and delay the epidemic curve, according to the model findings. The model result shows that most new events and hospitalizations were avoided when social distancing measures were in effect. Social distancing can provide a critical time for increasing healthcare capability, and the research findings could assist policymakers in estimating the immediate number of resources required and planning for potential COVID-19 initiatives in Ethiopia.

Dynamics of the COVID-19 epidemic in the post-vaccination period in Korea: a rapid assessment

OBJECTIVES

Coronavirus disease 2019 (COVID-19) has had a tremendous impact on public health and socioeconomic conditions globally. Although non-pharmaceutical interventions (NPIs) such as social distancing effectively reduced the incidence of COVID-19, especially in Korea, demand for vaccination has increased to minimize the social costs of NPIs. This study estimated the potential benefits of COVID-19 vaccination in Korea.

METHODS

A mathematical model with vaccinated-susceptible-latent-infectious-recovered compartments was used to simulate the COVID-19 epidemic. The compartments were stratified into age groups of 0-19 years, 20-59 years, and 60 years or older. Based on the Korea Disease Control and Prevention Agency national vaccination plan for the second quarter of 2021, announced on March 15, we developed vaccination scenarios (with 150,000 dose/d and 100% compliance as the main scenario). Comparing scenarios without vaccination or with higher/lower vaccination rates and compliance, we estimated the numbers of COVID-19 cases that will be prevented by vaccination.

RESULTS

The results projected 203,135 cases within a year after April 2021 without vaccination, which would be reduced to 71,248 (64.9% decrease) by vaccination. Supposing a vaccination rate of 150,000 dose/d and 100% compliance, social distancing interventions for those aged 20 or more can be retracted after January 1, 2022.

CONCLUSIONS

We expect COVID-19 vaccination to be effective in Korea. Health authorities should minimize delays in vaccination and vaccine avoidance to maximize the effectiveness of vaccination and end social distancing early.

Non-pharmaceutical interventions during the COVID-19 pandemic: A review

Infectious diseases and human behavior are intertwined. On one side, our movements and interactions are the engines of transmission. On the other, the unfolding of viruses might induce changes to our daily activities. While intuitive, our understanding of such feedback loop is still limited. Before COVID-19 the literature on the subject was mainly theoretical and largely missed validation. The main issue was the lack of empirical data capturing behavioral change induced by diseases. Things have dramatically changed in 2020. Non-pharmaceutical interventions (NPIs) have been the key weapon against the SARS-CoV-2 virus and affected virtually any societal process. Travel bans, events cancellation, social distancing, curfews, and lockdowns have become unfortunately very familiar. The scale of the emergency, the ease of survey as well as crowdsourcing deployment guaranteed by the latest technology, several Data for Good programs developed by tech giants, major mobile phone providers, and other companies have allowed unprecedented access to data describing behavioral changes induced by the pandemic. Here, I review some of the vast literature written on the subject of NPIs during the COVID-19 pandemic. In doing so, I analyze 348 articles written by more than 2518 authors in the first 12 months of the emergency. While the large majority of the sample was obtained by querying PubMed, it includes also a hand-curated list. Considering the focus, and methodology I have classified the sample into seven main categories: epidemic models, surveys, comments/perspectives, papers aiming to quantify the effects of NPIs, reviews, articles using data proxies to measure NPIs, and publicly available datasets describing NPIs. I summarize the methodology, data used, findings of the articles in each category and provide an outlook highlighting future challenges as well as opportunities.

Mass Testing With Contact Tracing Compared to Test and Trace for the Effective Suppression of COVID-19 in the United Kingdom: Systematic Review

BACKGROUND

Making testing available to everyone and tracing contacts might be the gold standard to control COVID-19. Many countries including the United Kingdom have relied on the symptom-based test and trace strategy in bringing the COVID-19 pandemic under control. The effectiveness of a test and trace strategy based on symptoms has been questionable and has failed to meet testing and tracing needs. This is further exacerbated by it not being delivered at the point of care, leading to rising cases and deaths. Increases in COVID-19 cases and deaths in the United Kingdom despite performing the highest number of tests in Europe suggest that symptom-based testing and contact tracing might not be effective as a control strategy. An alternative strategy is making testing available to all.

OBJECTIVE

The primary objective of this review was to compare mass testing and contact tracing with the conventional test and trace method in the suppression of SARS-CoV-2 infections. The secondary objective was to determine the proportion of asymptomatic COVID-19 cases reported during mass testing interventions.

METHODS

Literature in English was searched from September through December 2020 in Google Scholar, ScienceDirect, Mendeley, and PubMed. Search terms included "mass testing," "test and trace," "contact tracing," "COVID-19," "SARS-CoV-2," "effectiveness," "asymptomatic," "symptomatic," "community screening," "UK," and "2020." Search results were synthesized without meta-analysis using the direction of effect as the standardized metric and vote counting as the synthesis metric. A statistical synthesis was performed using Stata 14.2. Tabular and graphical methods were used to present findings.

RESULTS

The literature search yielded 286 articles from Google Scholar, 20 from ScienceDirect, 14 from Mendeley, 27 from PubMed, and 15 through manual search. A total of 35 articles were included in the review, with a sample size of nearly 1 million participants. We found a 76.9% (10/13, 95% CI 46.2%-95.0%; P=.09) majority vote in favor of the intervention under the primary objective. The overall proportion of asymptomatic cases among those who tested positive and in the tested sample populations under the secondary objective was 40.7% (1084/2661, 95% CI 38.9%-42.6%) and 0.0% (1084/9,942,878, 95% CI 0.0%-0.0%), respectively.

CONCLUSIONS

There was low-level but promising evidence that mass testing and contact tracing could be more effective in bringing the virus under control and even more effective if combined with social distancing and face coverings. The conventional test and trace method should be superseded by decentralized and regular mass rapid testing and contact tracing, championed by general practitioner surgeries and low-cost community services.

Effectiveness of non-pharmaceutical interventions on COVID-19 transmission in 190 countries from 23 January to 13 April 2020

BACKGROUND

To evaluate and compare the effectiveness of four types of non-pharmaceutical interventions (NPIs) to contain the time-varying effective reproduction number (Rt) of coronavirus disease-2019 (COVID-19).

METHODS

This study included 1,908,197 confirmed COVID-19 cases from 190 countries between 23 January and 13 April 2020. The implemented NPIs were categorised into four types: mandatory face mask in public, isolation or quarantine, social distancing and traffic restriction (referred to as mandatory mask, quarantine, distancing and traffic hereafter, respectively).

RESULTS

The implementations of mandatory mask, quarantine, distancing and traffic were associated with changes (95% confidence interval, CI) of -15.14% (from -21.79% to -7.93%), -11.40% (from -13.66% to -9.07%), -42.94% (from -44.24% to -41.60%) and -9.26% (from -11.46% to -7.01%) in the Rt of COVID-19 when compared with those without the implementation of the corresponding measures. Distancing and the simultaneous implementation of two or more types of NPIs seemed to be associated with a greater decrease in the Rt of COVID-19.

CONCLUSION

Our study indicates that NPIs can significantly contain the COVID-19 pandemic. Distancing and the simultaneous implementation of two or more NPIs should be the strategic priorities for containing COVID-19.