Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
No Protest-Related Increases in Coronavirus Infections: Early Data
Anti-racism protests in the United States haven't led to increases in new cases of the coronavirus that causes COVID-19, early data show.
The findings from a handful of cities are encouraging, and the use of masks and the fact that protests are outdoors may have helped, public health experts say, the Wall Street Journal reported.
However, the data is preliminary and protest-related infections could still rise, health officials caution.
As of Monday, 1.8% of tests among 3,200 protesters tested at community sites in Minnesota had come back positive, according to the state health department. The rate of positive tests was 0.99% among other protesters in Minnesota tested through health care providers or at other locations, WSJ reported.
In New York City, the seven-day rolling average of positive tests has been below 3%, and has been flat or in decline since June 5, city health department data show.
Officials in Seattle and Chicago said no increases in coronavirus cases related to protests have been detected, but the situation continues to be monitored, WSJ reported.
Too Much Sitting Increases Risk of Cancer Death: Study
Sitting too much could increase your risk of dying from cancer, a new study warns.
It included about 8,000 people without cancer whose physical activity over seven days was assessed using a tracking device. They were then followed for five years, CNN reported.
During that follow-up, the least active people had an 82% higher risk of dying from cancer than those with the highest levels of physical activity, according to the study in the journal JAMA Oncology.
"This is the first study that definitively shows a strong association between not moving and cancer death," said lead author Dr. Susan Gilchrist, associate professor of clinical cancer prevention, MD Anderson Cancer Center, University of Texas, CNN reported.
However, she added that replacing at least 30 minutes of sitting with either light, moderate or vigorous physical activity may reduce the risk.
Journal Should Retract Mask Study: Scientists
A study on the use of masks to protect against the new coronavirus should be retracted by the journal Proceedings of the National Academy of Sciences because it contains "egregious errors" and "verifiably false" statements, a group of scientists say in a letter to the journal's editors.
The study was published June 11 and claims that wearing a mask "significantly reduces the number of infections" with the new coronavirus and that "other mitigation measures, such as social distancing implemented in the United States, are insufficient by themselves in protecting the public," The New York Times reported.
The study also said that airborne transmission is the main way the coronavirus spreads.
The scientists who want the study retracted say that while the study supports others that have concluded that masks help protect against the new coronavirus, the methodology of the study is deeply flawed, The Times reported.
For example, the authors assumed that people's behavior shifted immediately after policy changes and didn't take into account the huge societal changes that may have affected the reported incidence of coronavirus infection.
"There is evidence from other studies that masks help reduce transmission of COVID-19, but this paper does not add to that evidence," said Linsey Marr, an expert on airborne transmission of viruses at Virginia Tech, The Times reported.
The scientists asked the journal to retract the study immediately "given the scope and severity of the issues we present, and the paper's outsized and immediate public impact."
The study's lead author, Mario Molina, was postdoctoral adviser to Marr. For his part, Molina defended the research.
"We show in the paper itself that we know things are complicated, we know that there's social distancing, we know that it's sometimes perfect, sometimes not," Molina told The Times. "They just didn't understand our paper."
Molina won the Nobel Prize in Chemistry in 1995.
"The journal is aware of concerns raised about this article and is looking into the matter," according to a journal spokeswoman, The Times reported.
Coronavirus Antibodies May Not Last Long: Study
Even if people develop antibodies after infection with the new coronavirus, they may last only two to three months, and decline more in those who didn't have symptoms, a new study suggests.
The researchers said their findings show the need to be cautious about the idea of "immunity certificates" for people who have recovered from infection, The New York Times reported.
A number of studies have shown that most people infected with the new coronavirus develop antibodies to it, but it wasn't known how long the antibodies last.
They study was conducted in China and included 37 infected people with symptoms and 37 without symptoms. Antibodies -- protective proteins produced in response to an infection -- fell to undetectable levels in 40% of asymptomatic people, compared with 13% of symptomatic people, according to the study in the journal Nature Medicine.
Several experts said the findings don't necessarily mean that people with low levels of antibodies to the new coronavirus can be infected a second time, The Times reported.
It's believed that antibodies to other coronaviruses, including those that cause SARS and MERS, are believed to last about a year, and it was hoped that antibodies to the new coronavirus might endure at least as long.