April 19, 2022
2 min read
Source/Disclosures
Disclosures:
Bhatt reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
SARS-CoV-2 spreads extensively in households, with children being a significant source of that spread, a Canadian study reported last week.
Study co-author Maala Bhatt, MD, MSc, FRCPC, is director of emergency medicine research at the Children’s Hospital of Eastern Ontario (CHEO), an investigator at the hospital’s research institute, and associate professor of pediatrics at the University of Ottawa.
SARS-CoV-2 spreads extensively in households, with children being a significant source of that spread, a Canadian study found. Source: NIH
“Our study was conducted when we were dealing with a less transmissible virus and pandemic restrictions were strongly in place, and we still had a 50% transmission rate within households,” Bhatt said in a statement. “Flash forward to where we are today, with an extremely transmissible variant of COVID-19 and the majority of pandemic restrictions lifted; it’s safe to say transmission rates will be higher even though we have a high vaccination rate amongst those who are eligible.”
The study examined 695 participants, 340 children and 355 adults, from 180 households in Ottawa between September 2020 and March 2021, with each household having at least one child in residence. A total of 487 household contacts (94.6%) (246 children, 241 adults) had SARS-CoV-2 antibody testing, of whom 239 had a positive result (secondary attack rate 49.1%, 95% confidence interval [CI] 42.9%–55.3%). Of the positive-testing contacts, 88 (36.8%, 95% CI 29.3%–43.2%) were asymptomatic; a rate similar for children (51/130 [39.2%, 95% CI 30.7%– 48.5%]) and adults (37/115 [32.2%, 95% CI 24.2%–41.4%]) (odds ratio [OR] 1.3, 95% CI 0.8–2.1).
While the researchers found that adults were more likely than children to transmit SARS-CoV-2 (OR 2.2, 95% CI 1.3–3.6). The odds of transmission from asymptomatic (OR 0.6, 95% CI 0.2–1.4) versus symptomatic (OR 0.9, 95% CI 0.6–1.4) index participants to household contacts was uncertain.
“People with SARS-CoV-2 infection transmitted extensively within their households, with a secondary attack rate of about 50%,” they wrote in conclusion. “Although children transmitted at a lower rate than adults, they still infected one-third of household members.”
“I know many want to ‘live with COVID’ and abandon the layers of protection that were previously mandated, but it’s important to be aware of the high transmissibility of this virus in closed, indoor settings, such as schools,” Bhatt said. “Our most vulnerable and our youngest children who are not yet able to be vaccinated are still at risk for COVID infection.”
References:
“COVID-19 household transmission is high, with children being a significant source of spread: study.” https://www.eurekalert.org/news-releases/949558. Published April 12, 2022. Accessed April 18, 2022.
COVID-19 Resource Center