Explanation-What Researchers Say About Long-Term Effects Of COVID-19, Health News, ET HealthWorld
NEW YORK – The World Health Organization (WHO) this week released a definition of “long COVID,” a term used to describe persistent health problems that affect some COVID-19 survivors. Scientists are still working to understand the syndrome. Here’s what they know so far.
HOW DOES THE WHO DEFINE LONG COVID?
WHO defines long-term COVID as a condition with at least one symptom that typically begins within three months of the onset of confirmed or probable coronavirus infection, persists for at least two months, and cannot be explained by a other diagnosis. Symptoms may appear during infection or may first appear after the patient has recovered from acute illness.
Among the most common persistent symptoms are fatigue, shortness of breath, and cognitive problems. Others include chest pain, problems with smell or taste, muscle weakness, and heart palpitations. Long COVID generally has an impact on daily functioning.
The WHO definition may change as new evidence emerges and the understanding of the consequences of COVID-19 continues to evolve. A separate definition may be applicable for children, the agency said.
HOW FREQUENCY IS LONG COVID?
The exact number of people affected is not known. A University of Oxford study of more than 270,000 COVID-19 survivors found at least one in 37% long-term symptom, with symptoms more common in people who had to be hospitalized.
A separate Harvard University study involving more than 52,000 COVID-19 survivors whose infections had only been mild or asymptomatic suggests that long-lasting COVID conditions may more often affect patients under 65 years of age.
More than 236 million infections caused by the coronavirus have been reported so far, according to a Reuters tally.
WHAT ELSE STUDIES SHOW ABOUT LONG COVID SYMPTMS?
In a study published in the Lancet, Chinese researchers reported that 12 months after leaving the hospital, 20-30% of patients who had been moderately ill and up to 54% of those who were seriously ill still had problems pulmonary.
The Harvard study also found that new diagnoses of diabetes and neurological disorders are more common in people with a history of COVID-19 than in those without infection.
DO PEOPLE RECOVER FROM LONG COVID?
Many symptoms of a long COVID-19 go away over time, regardless of the severity of the initial COVID-19 illness. The proportion of patients still showing at least one symptom rose from 68% at six months to 49% at 12 months, according to the study published in The Lancet.
The WHO has said long symptoms of COVID can change over time and return after showing initial improvement.
DO COVID-19 VACCINES HELP WITH LONG COVID?
Small studies have suggested that some people with long-standing COVID experienced improvement in their symptoms after being vaccinated. The U.S. Centers for Disease Control and Prevention said more research is needed to determine the effects of vaccination on post-COVID conditions.