In this Aug. 31, 2021 file photo a R.N. holds the hand of a COVID-19 patient in the Medical Intensive care unit at St. Luke's Boise Medical Center in Boise, Idaho. Credit: Kyle Green / AP

LOS ANGELES — A new study has found that 1 in 3 people who survived COVID-19 suffer from long COVID.

The study of Long Beach residents published by the U.S. Centers for Disease Control and Prevention on Thursday found that these long COVID patients reported at least one symptom of COVID-19 two months after first testing positive for the coronavirus.

There were higher rates of long COVID among people 40 or older, women, people with preexisting health conditions and Black residents, according to the study, conducted by the University of California, Davis epidemiologists and the Long Beach Department of Health and Human Services.

The survey was based on the responses of 366 adults in Long Beach who tested positive for the virus last year, before vaccinations were authorized for emergency use and began to be rolled out to health care workers.

The study found that 35 percent of survey respondents reported at least one ongoing symptom of COVID-19 two months after the initial positive test.

Fatigue was reported by 17 percent of those long COVID patients; difficulty breathing and loss of taste or smell were reported by 13 percent; and muscle or joint pain was reported by 11 percent.

The study authors said the results are important to help experts “develop efforts to prioritize prevention and treatment strategies for” populations at higher risk of long COVID.

The study’s results are limited by the relatively small number of people surveyed, and it wasn’t possible to attribute symptoms to COVID-19 versus those that existed before coronavirus infection. It’s also possible that people with long COVID symptoms were more likely to respond to the survey, according to the report, meaning the study might potentially overstate the problem.

“Further research, including research over longer periods, is warranted,” the study said.

The study was published in the CDC’s Morbidity and Mortality Weekly Report.

Experts say that vaccination not only reduces the chance of falling ill with COVID-19, but also probably reduces the chance of enduring long COVID should a vaccinated person contract a breakthrough infection.

Vaccinated people are far less likely to be infected or get severely ill from COVID-19 than unvaccinated people.

“If the virus can’t take hold in your body — if it can’t get into your system and if it can’t start replicating — then it doesn’t have a chance to get to the point where you might translate into having long-haul symptoms,” Dr. Christina Ghaly, the L.A. County director of health services, said this year.

Story by Rong-Gong Lin II and Luke Money, Los Angeles Times