According to a study published in the journal of Annals of Internal Medicine, household contact was the main setting for transmission of SARS-CoV-2, and the risk for transmission of SARS-CoV-2 among close contacts increased with the severity of index cases.
The authors of the study examined settings of Covid-19 transmission in a cohort study of 3410 close contacts of 391index cases of Covid-19 in Guangzhou, China.
“We wanted to evaluate the risk for transmission of SARS-CoV-2 to close contacts of persons infected with Covid-19 in Guangzhou region,” said study researchers from Southern Medical University in China.
The study was then classified into 5 subcategories: household, public transportation, health care settings, entertainment venues or workplaces, and multiple settings. “Multiple settings” indicates exposure in more than 1 contact setting.
The study found that the secondary attack rate was less than 4 per cent among close contacts of persons with Covid-19.
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