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  • A new study finds that being vaccinated against COVID-19 does not fully protect you from getting long COVID.
  • A study looked at data from the Department of Veterans Affairs.
  • They found people who were vaccinated were only 15 percent less likely to get long COVID compared to people who were not vaccinated.

While vaccination remains our best defense against the most severe outcomes of COVID-19, long COVID is still possible if you experience a breakthrough infection.

New research from the Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care System finds even vaccinated people with mild breakthrough infections may experience potentially debilitating symptoms.

For this study published today in Nature Medicine, researchers analyzed the medical records of over 13 million veterans stored in a Department of Veterans Affairs (VA) database.

They analyzed data from 113,474 unvaccinated COVID-19 patients and nearly 34,000 fully vaccinated patients who experienced COVID-19 breakthrough infections from Jan. 1 through Oct. 31, 2021.

Patients were considered fully vaccinated if they received two doses of the Moderna or Pfizer vaccines or one dose of the Johnson & Johnson vaccine.

Although the patients were mostly older, white men, the researchers also analyzed data including almost 1.5 million women and adults of all ages and races.

The team looked at how people with breakthrough infections were doing six months after their diagnosis.

Researchers found that vaccinated people were about 15 percent less likely to develop long COVID than people who were not vaccinated.

Study findings also indicated that long COVID risk was 17 percent higher among vaccinated immunocompromised people with breakthrough infections compared to previously healthy, vaccinated people.

Researchers also compared long-term health outcomes with a pre-pandemic control group of nearly 6 million people that never had COVID-19.

They found people with breakthrough infections had a significantly higher risk of death, diseases of major organs, and neurological conditions.

Also, vaccinated people hospitalized with breakthrough infections had a 2.5 times higher risk of death than those hospitalized with flu.

Those hospitalized with breakthrough infections also had a 27 percent higher risk of long COVID 30 days after diagnosis.

The study was conducted before the rise of Omicron, which affected a significant number of Americans. Additionally, it was conducted before new COVID-19 antivirals, including Pfizer’s Paxlovid, were widely available. So it is possible that current findings of long COVID risk for vaccinated people could be different.

First author Ziyad Al-Aly, MD, a clinical epidemiologist at Washington University, told Healthline that the research team had two goals:

  • To determine if the condition can happen in people with breakthrough infections
  • Find out whether and to what extent vaccination could reduce long COVID risk

“Essentially, we wanted to know if vaccines can protect us from long COVID and how much protection is conferred by vaccination,” he said.

Asked about the findings, Al-Aly expressed his disappointment.

“We were hoping to see that vaccines would be protective,” he said. “But alas, the results showed us otherwise.”

Al-Aly said the findings suggest that vaccines are an “imperfect shield.”

“They only modestly protect from long COVID,” he explained. “And that reliance on them as a sole layer of protection is not optimal.”

According to Al-Aly, urgent research is needed to develop “additional layers of protection,” like other types of vaccines or medications that could help mitigate the long-term consequences of COVID.

According to Robert Lahita, MD, director of the Institute for Autoimmune and Rheumatic Disease at Saint Joseph Health and author of “Immunity Strong,” breakthrough infection means the virus can evade our immune response.

“Viruses are very resilient and hardy,” he said. “They are constantly up-mutating and down-mutating.”

Lahita emphasized that COVID vaccines provide enough adaptive immunity to protect most people from severe infection for long periods.

“The innate immune response is present in everyone, but again this varies from individual to individual,” he said.

Another recent study found the neurological effects of long COVID could persist for over a year.

The small study of 52 people found that 85 percent of patients with mild COVID reported at least four lasting neurological problems at least six weeks after acute infection. About 80 percent of the participants were vaccinated.

They reported that symptoms persisted for 15 months on average, and while most saw improvements in cognitive function and fatigue, symptoms hadn’t completely resolved and continued affecting their quality of life.

“Long COVID has a variety of symptoms, and everyone has a different presentation,” said Natalia Covarrubias-Eckardt, MD, Medical Director of Inpatient Rehabilitation and the Post-COVID Rehabilitation Program at Providence St. Jude Medical Center in Orange County, Calif.

She said the most common symptoms are fatigue, headaches, difficulty thinking or concentrating, shortness of breath, anxiety, and depression.

Covarrubias-Eckardt said there are ways to treat symptoms of long COVID and that most people do recover.

“For patients who have fatigue, for example, we teach them pacing and gradually increase their activity tolerance,” she explained. “For those with difficulty thinking or concentrating, we have therapists trained in cognitive recovery with various exercises and supportive treatments.”

Covarrubias-Eckardt noted that there are no specific medications to treat it at this time.

However, she pointed out it’s important that patients with ongoing symptoms make sure there isn’t another diagnosis causing their symptoms.

New research finds that vaccinated people who experience even mild breakthrough infections may experience long COVID.

Experts say while vaccination offers strong protection for most people, the virus challenges this by constantly mutating.