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Can vaccinated people get long Covid? Doctors say risk is 'very, very small'

It is theoretically possible for a fully vaccinated person to get long Covid. But doctors contend that it doesn't appear to be a significant risk.
A woman receives a Covid-19 vaccine from a registered nurse at the Roosevelt Family Health Center of Long Island in Roosevelt, N.Y., on July 8, 2021.
A woman receives a Covid-19 vaccine from a registered nurse at the Roosevelt Family Health Center of Long Island in Roosevelt, N.Y., on July 8, 2021.Steve Pfost / Newsday RM via Getty Images file

Coronavirus infections leading to long-haul Covid-19 in fully vaccinated people are probably very rare, experts say.

The Covid-19 vaccines have been shown to significantly reduce infections, as well as the risk of severe consequences of the illness, including hospitalization and death. That means that if a fully vaccinated person does become infected, the illness is much more likely to be mild.

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But for many Covid-19 long-haulers, it was a mild infection that set off their lingering symptoms, leaving many to wonder whether a mild breakthrough case in someone who is fully vaccinated could do the same.

It is theoretically possible, experts say, for that to occur. But doctors treating Covid-19 patients across the country contend that it doesn't appear to be a significant risk.

Breakthrough infections resulting in long Covid-19 are "quite rare," said Dr. Greg Vanichkachorn, an occupational medicine specialist who works with post-Covid-19 syndrome patients at the Mayo Clinic in Rochester, Minnesota.

Vanichkachorn's observation, while based only on what he's seen in the clinic, is echoed at other post-Covid-19 clinics.

Dr. Michele Longo, an assistant professor of neurology at Tulane University in New Orleans who works with long-haul patients, said she has not seen such patients following a breakthrough infection. Neither has Dr. Maureen Lyons, medical director of the Care and Recovery from Covid-19 Clinic at Washington University in St. Louis.

Dr. Ziyad Al-Aly, a clinical epidemiologist, also at Washington University, is studying the effects of Covid-19 vaccination on the risk of long Covid-19. His research, which is not yet finished, looks at information on more than 5 million veterans within a Department of Veterans Affairs database, including 200,000 who were diagnosed with Covid-19.

"Of the people who get vaccinated and end up with a breakthrough infection, their risk of coming back to the clinic with some long Covid manifestation is very, very small," Al-Aly said.

Lyons cautioned that the lack of observed post-Covid-19 cases in vaccinated people "just might be a lag time issue." That is, because Covid-19 vaccinations started rolling out en masse within the past three to four months, it is possible that not enough time has passed to identify long-haul patients following their vaccinations.

Dr. Natasha Altman, a cardiologist at UCHealth University of Colorado Hospital in Aurora, agreed that it may be too soon to understand the vaccines' effects on long-term Covid-19 symptoms.

"I think the trends are going to only really going to start bearing out in the next six months," she said.

Al-Aly acknowledged that possibility. "It is possible that down the road we may discover that maybe the vaccine only delayed the inevitable," he said.

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But because the vaccines have been proven to dramatically cut the risk of Covid-19 infection in general, the shots remain "one of the best ways to lower your risk of getting post-Covid syndrome," Vanichkachorn said.

It is estimated that up to a third of Covid-19 cases may result in long-term illness. That suggests that of the nearly 34 million people diagnosed with Covid-19 in the United States, about 11 million may endure consequences of the illness for months or years.

"While everyone else is moving on with life," Longo said, the long-haulers "are still stuck in a rut struggling with this virus."

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