January 19, 2021

Do in-person classes drive Covid-19 spread? Here's what new research reveals.

Daily Briefing

    A number of schools throughout the country have reopened for in-person classes, and more are planning on reopening soon. But are children who attend in-person classes more at greater risk of catching the new coronavirus than those who don't?

    Weekly line: The 3 biggest obstacles to reopening schools

    CDC study finds children who attend in-person classes likely aren't at higher risk

    A new study from CDC indicates that children who attend in-person classes likely aren't at higher risk of contracting the novel coronavirus than those who don't.

    For the study, researchers looked at data on confirmed cases of coronavirus infections among children, adolescents, and young adults up to age 24 between March 1, 2020, and Dec. 12, 2020, that was reported by 44 states, the District of Columbia, two U.S. territories, and one freely associated state.

    According to CDC researchers, there were nearly three million confirmed and reported coronavirus infections among children, adolescents, and young adults in the areas included in the data. Incidence rates varied by age group, with almost 60% of the reported cases occurring among adults ages 18 to 24.

    Between March 1, 2020, and Dec. 12, 2020, around 62% of K-12 school districts offered either full or partial in-person learning, CDC researchers said. However, they found that reports of coronavirus outbreaks at schools were limited.

    In addition, the researchers found that coronavirus case rates among the general population were about the same in counties where schools were open for in-person learning and in those that employed online schooling only. According to the researchers, higher rates of coronavirus cases among adults were not preceded by increased case rates among children or adolescents.

    The researchers said that, based on the lower percentage of cases among younger children, the risk of coronavirus transmission "might be lower" in child-care centers and elementary schools when compared with high schools and other higher-learning institutions. For instance, they wrote, "In contrast to the evidence regarding K–12 school reopenings, previous studies provide evidence for increased community incidence in counties where institutions of higher education reopened for in-person instruction."

    Overall, the researchers wrote that "[s]chools provide a structured environment that can support adherence to critical mitigation measures to help prevent and slow the spread of Covid-19." However, they added that "[s]uccess in preventing introduction and transmission of [the novel coronavirus] in schools depends upon both adherence to mitigation strategies in schools and controlling transmission in communities."

    The researchers cautioned, "When community transmission is higher, cases in schools should be expected, and as with any group setting, schools can contribute to Covid-19 transmission, especially when mitigation measures such as universal and proper masking are not implemented or followed."

    Erin Sauber-Schatz, an epidemiologist with CDC and the leader of CDC's community interventions and critical populations task force, said CDC is recommending "that child-care centers and schools, especially elementary schools, be the last settings to close after all other mitigation measures are deployed, and the first to reopen."

    In another new study, researchers advise caution

    In a separate study published Monday in JAMA Pediatrics, however, researchers found that although coronavirus infection rates may be lower among children than adults, children are still at a notable risk of developing a severe case of Covid-19.

    For the study, researchers looked at data from 22 states on 5,364 patients ages 19 and younger who had been hospitalized for Covid-19 between May 15, 2020, and Nov. 15, 2020.

    The researchers found that in May of last year, the hospitalization rate among children was 2 per 100,000. That rate increased to 17.2 per 100,000 children in November 2020, the researchers found—and that rate had increased at more than double the growth seen among adult patients during the same time period, according to Pinar Karaca-Mandic, a health economics expert at the University of Minnesota and senior author on the study.

    "This demonstrates that Covid still has the potential to cause serious illness in children," Karaca-Mandic said. "It's not like children are immune. It's not like children are not at risk."

    Karaca-Mandic added that, while older adults are at the greatest risk of developing a severe case of Covid-19, it's important to note that some hospitals may not be prepared to care for younger patients who develop severe cases of the disease.

    "Sometimes I feel like the message of 'lower risk' in children may have been misinterpreted as 'no risk' by many," she said. "Our study is showing that is not the case" (Hellmann, The Hill, 1/13; Rabin, New York Times, 1/13).

    How Covid-19 is changing the future of the health care industry


    Read on to get Advisory Board's take on how Covid-19 will reshape demand, purchaser strategies, the competitive landscape, and delivery models.

    Get our Take

    Have a Question?


    Ask our experts a question on any topic in health care by visiting our member portal, AskAdvisory.

    Cookies help us improve your website experience. By using our website, you agree to our use of cookies.