A subtype of the Delta variant is causing a growing number of infections in the United Kingdom and is being closely monitored there and in other countries. During the week of Sept. 27, the AY.4.2 variant accounted for about 6% of cases in the U.K. and is “on an increasing trajectory,” according to the U.K.…  read on >  read on >

You’ve probably heard that getting better sleep can be good for your waistline. The same appears to be true for your baby. Newborns who get more sleep and wake up less during the night are less likely to become overweight in infancy, according to a just-published study. “While an association between insufficient sleep and weight…  read on >  read on >

When a pregnant woman is infected with COVID-19, the sex of the fetus may influence immune system activity, researchers say. The new study included 68 mothers-to-be. Thirty-eight developed COVID-19 during their third trimester, while 30 remained virus-free. In both groups, half of the fetuses were male and half were female. In the infected women, male…  read on >  read on >

Nine of 10 patients with so-called “bubble boy” immune disease who received gene therapy about a decade ago are still disease-free, researchers report. The gene therapy was developed at the University of California, Los Angeles (UCLA), to treat the rare and deadly immune system disorder formally known as adenosine deaminase–deficient severe combined immunodeficiency (ADA-SCID). It’s…  read on >  read on >

Obese people have a tougher time fighting COVID-19, even if they have a milder form of the virus, a new study finds. Researchers looked at more than 500 patients who tested positive for COVID but didn’t require hospitalization. Teens and adults who were overweight or obese had more symptoms, including cough and shortness of breath,…  read on >  read on >

Smokers may think electronic cigarettes will help them quit, but a new study finds no evidence that’s the case. Researchers found that among Americans who’d recently quit smoking, those who were using e-cigarettes were just as likely to relapse in the next year as non-users were. And the risk of relapse was actually slightly increased…  read on >  read on >