As the corona virus disease 2019 (COVID-19) pandemic continues around the world, understanding the transmission characteristics of COVID-19 is vital for prevention and control. We conducted the first study aiming to estimate and compare the relative risk of secondary attack rates (SARs) of COVID-19 in different contact environments. Until 26 July 2021, epidemiological studies and cluster epidemic reports of COVID-19 were retrieved from SCI, Embase, PubMed, CNKI, Wanfang and CBM in English and Chinese, respectively. Relative risks (RRs) were estimated in pairwise comparisons of SARs between different contact environments using the frequentist NMA framework, and the ranking of risks in these environments was calculated using the surface under the cumulative ranking curve (SUCRA). Subgroup analysis was performed by regions. Thirty-two studies with 68 260 participants were identified. Compared with meal or gathering, transportation (RR 10.55, 95% confidence interval (CI) 1.43–77.85), medical care (RR 11.68, 95% CI 1.58–86.61) and work or study places (RR 10.15, 95% CI 1.40–73.38) had lower risk ratios for SARs. Overall, the SUCRA rankings from the highest to the lowest were household (95.3%), meal or gathering (81.4%), public places (58.9%), daily conversation (50.1%), transportation (30.8%), medical care (18.2%) and work or study places (15.3%). Household SARs were significantly higher than other environments in the subgroup of mainland China and sensitive analysis without small sample studies (<100). In light of the risks, stratified personal protection and public health measures need to be in place accordingly, so as close contacts categorising and management.
【저자키워드】 COVID-19, Network meta-analysis, Contact environment, secondary attack rate, 【초록키워드】 pandemic, SARS, risk, Transmission, Relative risk, China, Epidemic, Characteristics, household, management, Cluster, Medical care, SAR, Care, Prevention and control, Analysis, close contact, Contact, Virus Disease, risk ratios, relative risks, attack rates, public health measure, 95% CI, 95% confidence interval, epidemiological studies, public health measures, Chinese, lower risk, participant, subgroup analysis, Pairwise comparison, Epidemiological study, ranking, CNKI, Household SARs, meal, pairwise comparisons, SUCRA, cumulative, regions, English, lowest, highest, conducted, was performed, calculated, significantly higher, stratified, CBM, NMA, retrieved, RRs, 【제목키워드】 Contact,