At least 50 percent of people who survive covid-19 experience a variety of physical and psychological health issues for six months or more after their initial recovery, according to research on the long-term effects of the disease, published in the journal JAMA Network Open.

Often referred to as “long covid,” the adverse health effects vary from person to person. But the research, based on data from 250,351 adults and children, found that more than half experience a decline in general well-being, resulting in weight loss, fatigue, fever or pain.

About 20 percent have decreased mobility, 25 percent have trouble thinking or concentrating (called “brain fog”), 30 percent develop an anxiety disorder, 25 percent have breathing problems, and 20 percent have hair loss or skin rashes. Cardiovascular issues — chest pain and palpitations — are common, as are stomach and gastrointestinal problems.

Those affected by post-covid conditions, sometimes called “long haulers,” can include anyone who has had covid-19, even those who had no symptoms or just mild ones, according to the Centers for Disease Control and Prevention.

But additional research published in a subsequent issue of the journal found that cognitive dysfunction has occurred more often among those who had more severe cases of covid-19 and required hospitalization, and their brain fog issues have lingered for seven months or more. “One’s battle with covid doesn’t end with recovery from the acute infection,” one researcher said.

— Linda Searing