Kids are half as susceptible...

People under age 20 may be almost half as susceptible to coronavirus as their elders— and less likely to transmit the disease to others. That’s the conclusion of a new Israeli study, which fitted statistical models of transmission to a data set of Covid testing results from 637 households. The researchers calculated that under-20s were 43 percent as susceptible as those over 20, and 63 percent as likely to spread the virus to others. They also found that children were more likely to receive a negative PCR test result despite being infected, suggesting they have a lower viral load. Lead researcher Itai Dattner, from the University of Haifa, tells ScienceDaily.com that understanding children’s role in transmission is a “top priority” for efforts around the world to reopen or keep open schools. Why children aren’t as affected remains unclear. But another study has quashed the theory that it is because they are more likely than adults to have antibodies to common-cold coronaviruses. On analyzing those antibodies, University of Pennsylvania researchers found that they neither disarmed the virus nor mitigated its symptoms.

drome linked to the coronavirus, The New York Times reports. The syndrome, called multisystem inflammatory syndrome in children, or MIS-C, remains rare: The Centers for Disease Control has recorded 2,060 cases in 48 states, Puerto Rico, and the District of Columbia, including 30 deaths. The median age of those affected was 9.

But the data show cases climbing since midOctober, and doctors say more of MIS-C patients require treatment in the intensivecare unit. “A higher percentage of them are really critically ill,” said Dr. Roberta DeBiasi, chief of infectious diseases at Children’s National Hospital in Washington, D.C. Symptoms—which seem to be connected to coronavirus infections—start with fever, rash, red eyes, and gastrointestinal problems, and can progress to heart dysfunction. Most of the affected kids survive, but doctors do not know if they will suffer lingering health problems in coming months or years. It’s unclear why MIS-C cases are rising, but it may correspond to the overall surge in coronavirus cases after the holidays.