COVID-19 outbreak and risk factors for infection in a taekwondo gym in the Republic of Korea

Causes of COVID-19 Outbreaks During Sports and Exercise: A Systematic Review

BACKGROUND

Physical activity is beneficial for preventing non-communicable and infectious diseases, such as pneumonia. Physical activity is also a potential protective factor for reducing coronavirus disease 2019 (COVID-19) severity. Conversely, outbreaks of respiratory viral infections are more likely to occur owing to group activities, opportunities for contact with individuals and vocalisations. Since the onset of the COVID-19 pandemic, several cases of COVID-19 outbreaks during various sports and exercise have been reported. However, the common causes underlying these outbreaks remain unclear.

OBJECTIVE

The objective of this study is to identify the causes of COVID-19 outbreaks during sports and exercise using systematic review approach.

METHODS

Our eligibility criteria were published articles reporting case investigation on COVID-19 outbreaks and the cause during sports and exercise. Studies such as reviews and observational studies without case investigations were excluded. PubMed, CINAHL, WHO COVID-19 Research Database and Ichushi Web were searched on 28 August 2023. The quality of included studies was rated using a quality criteria checklist adapted from a previous systematic review of influenza outbreaks. Vote counting of outbreak causes was performed by type of sports (team or individual).

RESULTS

Twenty-one articles reporting 22 outbreaks were identified (quality: high, 9; medium, 9; and low, 3). The outbreaks were most frequently reported in fitness classes, followed by soccer. Most studies listed multiple causes of the outbreaks. The most common suspected cause of outbreaks in individual exercise, mostly from fitness classes, was poor ventilation and not wearing masks, followed by not maintaining physical distance and participation of individuals with some symptoms. In team sports, the most common cause was interaction outside the game, such as social events.

CONCLUSIONS

This systematic review found a limited number of case investigations suggesting that COVID-19 outbreaks during sports and exercise may be associated with the inhalation of aerosols in indoor settings, interactions outside of team sports games and participation of individuals with some symptoms. Prevention strategies that focus on mitigating these issues may be effective at preventing sports and exercise-associated respiratory infectious diseases outbreaks.

PROSPERO REGISTRATION NUMBER

CRD42023443158.

The Risk of SARS-CoV-2 Transmission in Community Indoor Settings: A Systematic Review and Meta-analysis

BACKGROUND

Quantifying the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission in indoor settings is crucial for developing effective non-vaccine prevention strategies and policies. However, summary evidence on the transmission risks in settings other than households, schools, elderly care, and health care facilities is limited. We conducted a systematic review to estimate the secondary attack rates (SARs) of SARS-CoV-2 and the factors modifying transmission risk in community indoor settings.

METHODS

We searched Medline, Scopus, Web of Science, WHO COVID-19 Research Database, MedrXiv, and BiorXiv from 1 January 2020 to 20 February 2023. We included articles with original data for estimating SARS-CoV-2 SARs. We estimated the overall and setting-specific SARs using the inverse variance method for random-effects meta-analyses.

RESULTS

We included 34 studies with data on 577 index cases, 898 secondary cases, and 9173 contacts. The pooled SAR for community indoor settings was 20.4% (95% confidence interval [CI], 12.0%-32.5%). The setting-specific SARs were highest for singing events (SAR, 44.9%; 95% CI, 14.5%-79.7%), indoor meetings and entertainment venues (SAR, 31.9%; 95% CI, 10.4%-65.3%), and fitness centers (SAR, 28.9%; 95% CI, 9.9%-60.1%). We found no difference in SARs by index case, viral, and setting-specific characteristics.

CONCLUSIONS

The risk of SARS-CoV-2 transmission was highest in indoor settings where singing and exercising occurred. Effective mitigation measures such as assessing and improving ventilation should be considered to reduce the risk of transmission in high-risk settings. Future studies should systematically assess and report the host, viral, and setting-specific characteristics that may modify the transmission risks of SARS-CoV-2 and other respiratory viruses in indoor environments.

Identifying risk factors for COVID-19 cluster infections in schools in the Republic of Korea: a case-control study

BACKGROUND

No study has yet analyzed risk factors to determine whether students with confirmed coronavirus disease 2019 (COVID-19) infections may affect students at neighboring schools. Therefore, this study aimed to determine risk factors for COVID-19 transmission among schools within a community in the Republic of Korea.

METHODS

An epidemiological investigation was conducted among 696 students and school staff members at 3 schools where COVID-19 clusters began on October 15, 2021. Interviews, visit history surveys, a facility risk assessment, and closed-circuit television were used to identify risk factors. The statistical significance of risk factors was also evaluated.

RESULTS

We confirmed 129 cases (18.5%) among the individuals exposed to COVID-19 at the 3 schools, many of whom had a history of visiting the same multi-use facilities. The odds ratio of having visited multi-use facilities such as karaoke rooms was 1.90 (95% confidence interval, 1.03-3.50); the number of visits to a karaoke room and the visit durations were significantly higher among confirmed cases than non-confirmed cases (p=0.02 and p=0.03, respectively).

CONCLUSION

Having a history of visiting karaoke rooms often and spending a long time there were risk factors for COVID-19 infection and inter-school transmission. Thus, it is necessary to investigate the status of multi-use facilities frequently visited by adolescents and consider incorporating them into the scope of school quarantine to prevent infectious diseases at schools in a community.

Risk evaluation of venue types and human behaviors of COVID-19 outbreaks in public indoor environments: A systematic review and meta-analysis

Despite increasing vaccination rates, the incidence of breakthrough infections with COVID-19 has increased due to the continued emergence of new variants of the SARS-CoV-2 coronavirus. Therefore, Non-pharmaceutical interventions remain the most effective measures for coping with the ever-changing pandemic. The lifting of compulsory interventions has made individuals primary responsibility for their own health, which highlights the importance of increasing awareness of the infection risk from the environment in which they live and their individual behaviors. We systematically searched PubMed, Web of Science, ScienceDirect, and Scopus on April 17, 2023, for all studies reporting COVID-19 outbreaks in public indoor venues. The study outcome was the attack rate. A total of 42 studies, which included cross-sectional studies, cohort studies, and case studies, reporting data on 1951 confirmed cases in 64 COVID-19 outbreaks satisfied the meta-analysis and were included in the review. A random-effect model was used in the meta-analysis, and subgroup analyses were conducted to investigate factors affecting attack rates. We found a strong level of evidence (p < 0.01) supporting a higher pooled attack rate in recreation-related venues (0.44, 95% CI: 0.30 to 0.60) than in work-related venues (0.21, 95% CI: 0.16 to 0.27). Compared to those outbreaks without that, outbreaks with high-intensity exercise, vocalization, contact behavior, or close body proximity had a higher attack rate of 0.51, 0.55, 0.33, and 0.39, respectively. Further studies suggest that different attack rates across different types of settings may be the result of heterogeneity in exposed people's behaviors. There were significant heterogeneities that may limit the interpretation of connections between influencing factors and outbreak outcomes. The identification of key behaviors that may contribute to transmission risk, and their correlation with venue type, has important implications for the development of future public health interventions and individual prevention strategies for respiratory infectious diseases such as COVID-19.

SARS-CoV-2 transmission modes: Why and how contamination occurs around shared meals and drinks?

In spite of prevention measures enacted all over the world to control the COVID-19 pandemic outbreak, including mask wearing, social distancing, hand hygiene, vaccination, and other precautions, the SARS-CoV-2 virus continues to spread globally at an unabated rate of about 1 million cases per day. The specificities of superspreading events as well as evidence of human-to-human, human-to-animal and animal-to-human transmission, indoors or outdoors, raise questions about a possibly neglected viral transmission route. In addition to inhaled aerosols, which are already recognized as key contributors to transmission, the oral route represents a strong candidate, in particular when meals and drinks are shared. In this review, we intend to discuss that significant quantities of virus dispersed by large droplets during discussions at festive gatherings could explain group contamination either directly or indirectly after deposition on surfaces, food, drinks, cutlery, and several other soiled vectors. We suggest that hand hygiene and sanitary practices around objects brought to the mouth and food also need to be taken into account in order to curb transmission.

Risk factors for COVID-19 outbreaks in livestock slaughtering and processing facilities in Republic of Korea

BACKGROUND

The goal of this study was to help prevent and control the spread of coronavirus disease 2019 (COVID-19) by identifying transmission routes and risk factors in livestock slaughtering and processing facilities (SPFs) and establishing an optimal intervention strategy for outbreaks.

METHODS

This case series study was a demographic analysis of patients with confirmed COVID-19 associated with 5 SPFs in Korea between January and June 2021. Additionally, in a retrospective cohort study, the association between COVID-19 infection and risk factors was analyzed for SPFs at which outbreaks occurred.

RESULTS

The COVID-19 attack rates were 11.2%, 24.5%, and 6.8% at 3 poultry SPFs (PSPFs) and 15.5% and 25.2% at 2 mammal SPFs (MSPFs). Regarding spatial risk factors, the COVID-19 risk levels were 12.1-, 5.2-, and 5.0-fold higher in the refrigeration/ freezing, by-product processing, and carcass cutting areas, respectively, than in the office area. The risk of COVID-19 infection was 2.1 times higher among employees of subcontractors than among employees of contractors. The COVID-19 risk levels were 5.3- and 3.0-fold higher in foreign workers than in native Korean workers in the PSPFs and MSPFs, respectively.

CONCLUSION

As the COVID-19 pandemic continues, a detailed policy for infectious disease prevention and control intervention is needed, without interrupting economic activities. Thus, we propose an ideal intervention plan to prevent COVID-19 through disinfection and preemptive testing and to block its transmission through effective contact management during outbreaks at SPFs.