Image of man in bed with head on pillow, looking at alarm clock

The risk of developing long COVID was higher for the Alpha, Delta and wild-type variants of COVID-19 — and lower with omicron, according to new research.

A team based in Sweden published a study in The Journal of Infectious Diseases that found the risk for long COVID was higher with early variants. 

Research has shown that severe COVID-19 was less likely in people with omicron compared to the earlier variants. But scientists don’t know so much about how specific variants may boost a person’s likelihood of developing long COVID. Long COVID is defined as symptoms of COVID-19 that can last for 12 or more weeks after the initial infection. It can result in disability that may necessitate the need for long-term care.

The researchers looked at data from 3,002 people who were diagnosed with long COVID anywhere from 90 to 240 days after they first tested positive for SARS-CoV-2, the virus that causes COVID-19. The people were diagnosed between October 2020 and February 2022.

Even though more of the people studied got COVID-19 during the omicron phase, 0.2% of the people who had omicron had long COVID. That’s compared to 0.5% in those who had Delta, 1% in those who had Alpha and 1.3% in the wild-type cohort.

People with COVID-19 were 3.26 times more likely to get long COVID if they had Delta, 5.33 times more likely to get long COVID-19 if they had Alpha, and 6.31 times more likely to get long COVID if they had the wild-type variant.

Having to go into a hospital intensive care unit (ICU) was associated with developing long COVID regardless of which variant they had. Among those who had to go to the ICU for their infection, there weren’t significant differences in the variants people had with regard to developing long COVID.

Researchers just announced that the newer variant Pirola may not be as contagious as previous variants.