摘要
Objective:To study the transmission dynamics of coronavirus disease 2019(COVID-19)among 101 confirmed cases and their 387 household contacts and to determine risk factors associated with secondary attack among the household contacts.Methods:A prospective cohort study was conducted from January 1st 2021 to February 28th 2021,among 101 SARS-CoV-2 cases and 387 household contacts who were followed up for 14 days from the last day of contact with the index case of COVID-19.The dynamics of disease transmission was estimated,and factors affecting transmission risk were analyzed.Besides,the association between various factors and household secondary attack rate was determined.Results:The median incubation period was found to be 5 days,and the observed reproductive number(R)was found to be 1.63(95%CI:1.28-1.98).The mean household secondary attack rate was 40.7%.Contacts with comorbidities like diabetes mellitus,hypertension,dyslipidemia,and hypothyroidism had significantly higher attack rates(P<0.05).Conclusions:As new variants of SARS-CoV-2 emerges,it is crucial to know the trasmission dynamics.This study shows a high secondary attack rate of COVID-19 among household contacts that must be closely monitored.
