Long COVID affects more older adults; shots don't prevent it

New U.S. research on long COVID-19 provides fresh evidence that it can happen even after breakthrough infections in vaccinated people, and that older adults face higher risks for the long-term effects.

In a study of veterans published Wednesday, about one-third who had breakthrough infections showed signs of long COVID.

A separate report from the Centers for Disease Control and Prevention found that up to a year after an initial coronavirus infection, 1 in 4 adults aged 65 and older had at least one potential long COVID health problem, compared with 1 in 5 younger adults.

Long COVID refers to any of more than two dozens symptoms that linger, recur or first appear at least one month after a coronavirus infection. These can affect all parts of the body and may include fatigue, shortness of breath, brain fog and blood clots.

Coronavirus vaccines that help prevent initial infections and serious illnesses provide some protection against long COVID but mounting research shows not as much as scientists had first hoped.

The veterans study published in Nature Medicine reviewed medical records of mostly white male veterans, aged 60, on average. Of the 13 million veterans, almost 3 million had been vaccinated last year, through October.

About 1%, or nearly 34,000, developed breakthrough infections. Lead author Dr. Ziyad Al-Aly noted that the study was done before the highly contagious omicron variant appeared at the end of the year and said the rate of breakthrough infections has likely increased.

Breakthrough infections and long COVID symptoms were more common among those who had received Johnson & Johnson's single-dose shot compared with two doses of either Moderna or Pfizer vaccines. Whether any had received booster shots is not known; the first booster wasn't OK'd in...