The Scientist reports:

A new study is challenging the idea that younger children are somehow less susceptible to SARS-CoV-2 infection. Children under the age of five have been found to carry just as much, if not more, coronavirus in their noses and throats than older kids or adults.

The results, published Thursday (July 30) in JAMA Pediatrics, tested 145 people for evidence of the virus’s RNA. After breaking their participants down into three age categories—younger children, older children, and adults—researchers found that the youngest group harbored between 10 times and 100 times more virus than the other two. While the results cannot speak to children’s ability to transmit the disease to others, they come at a time when schools nationwide weighing the risks of opening again in the fall.

“The school situation is so complicated—there are many nuances beyond just the scientific one,” Taylor Heald-Sargent, a pediatric infectious diseases expert at the Ann and Robert H. Lurie Children’s Hospital and the lead author on the study, tells The New York Times. “But one takeaway from this is that we can’t assume that just because kids aren’t getting sick, or very sick, that they don’t have the virus.” [Continue reading…]

The Scientist also reports:

A preprint published on medRxiv July 23 reports that SARS-CoV-2–reactive antibodies were found in blood samples taken from people in the UK between 2018 and early 2020, before COVID-19 became widespread in the country.

Not only did the authors find that 15 out of 262 people who never had COVID-19 have IgG antibodies reactive with certain SARS-CoV-2 proteins, but further tests showed that these antibodies had a neutralizing effect on the SARS-CoV-2 spike protein, which suggests that they might be able to restrict infection by the virus.

One of the most striking findings was that these antibodies were far more prevalent in children between the ages of 1 and 16 years old. In fact, 60 percent of children had neutralizing IgG antibodies—an order of magnitude greater than the proportion of adults who were found to have the same antibodies. Coauthor Rupert Beale, an immunologist at the Francis Crick Institute in London, remarked on Twitter that this particular result was completely unexpected—“a kind of bombshell,” as he put it.

In their preprint, the authors write that kids are generally more frequently exposed to other coronaviruses, such as those that cause common colds. This could explain the prevalence of those IgG antibodies in their blood. [Continue reading…]