The household survey of the U.S. civilian non-institutionalized population used a nationally representative sample of about 17,000 adults age 18 and older. Of those, 8,275 adults reported having had covid-19, with some 1,200 indicating that they suffered from long covid symptoms.

The MEPS survey also asked participants about their covid-19 vaccination and booster shot history. Just 6 percent of the vaccinated and boosted respondents reported long covid symptoms vs. 8 percent of those who weren’t vaccinated. The findings suggest “booster shots may enhance protection against long covid, possibly because booster shots reduce the risk of severe covid-19,” the researchers wrote.

Long covid is defined as a condition with symptoms lasting three months or longer after an initial covid-19 infection, according to the Centers for Disease Control and Prevention. Long covid occurs more frequently in those who had severe covid-19, the CDC says.

The study also found significant differences in reported long covid symptoms between men and women, with women more likely to report symptoms in every age group — 9 percent of women vs. 5 percent of men. Respondents with underlying health conditions such as emphysema, chronic bronchitis and asthma were also more likely to report having long covid, as were White and Hispanic survey respondents.

Long covid can include a wide range of symptoms — including fatigue, brain fog, post-exertional malaise, coughing, fever and difficulty breathing. The CDC also notes that there isn’t a laboratory test that can definitively diagnose if symptoms are caused by long covid.

This article is part of The Post’s “Big Number” series, which takes a brief look at the statistical aspect of health issues. Additional information and relevant research are available through the hyperlinks.