A study published by the US Centers for Disease Control found that people are more likely to contract COVID-19 from members of their own households than from those outside the house.
The study, published July 16, looked in detail at 5,706 South Korean "index patients" who tested positive for the virus, and took into account over 59,000 people who came into contact with them, according to Reuters.
The findings showed just two out of 100 infected people had caught the virus from non-household contacts, while one in 10 had contracted the disease from their own families.
By age group, the infection rate within the household was higher when the first confirmed cases were teenagers or people in their 60s and 70s. -Reuters
"This is probably because these age groups are more likely to be in close contact with family members as the group is in more need of protection or support," said South Korea CDC (KCDC) Director Jeong Eun-kyeong, an author of the study.
Notably, South Korea has been militant about contact tracing - using apps to track and publish the routes of confirmed patients, as well as demographics such as patients' age, gender, neighborhood, businesses and apartment complexes they've visited and other metrics.
According to the study, children under the age of 10 were least likely to be the "index patient" - though children with the virus were also more likely to be asymptomatic than adults, making it harder to identify index cases within the group.
"The difference in age group has no huge significance when it comes to contracting COVID-19. Children could be less likely to transmit the virus, but our data is not enough to confirm this hypothesis," said Dr. Choe Young-june, a co-author of the study and assistant professor at Hallyum University College of Medicine.
South Korea has had 13,816 cases of coronavirus and 296 deaths.