Vaccination is highly effective at preventing the most serious cases of COVID-19 cases, but even some immunized people can develop what’s called a breakthrough infection, and it’s happening more often as the delta variant continues to spread. Both patients and providers now wonder whether or not vaccinations will prevent long COVID in breakthrough cases. Experts are divided on the issue. 

Long COVID To-Date

Long COVID, an array of debilitating symptoms that can persist for a month or more after an infection ends, typically includes such symptoms as fatigue, shortness of breath, heart palpitations, and “brain fog,” though some people develop more severe issues across multiple organs, including the lungs, heart, and brain. 

Unfortunately, the dearth of solid data concerning long COVID and breakthrough infections has made it difficult if not impossible for experts to state definitively whether or not vaccinated people can develop long COVID, or even estimate the likelihood of such an occurrence. The situation is further complicated by the CDC’s decision to stop tracking breakthrough cases as of May 1, 2021, except for those leading to hospitalization and death, using data from state and local health agencies. While the decision was made to “maximize the quality of the data collected on cases of greatest clinical and public health importance,” it has been met with opposition from some scientists. 

“In my opinion, CDC should be tracking all consequences of breakthrough cases, not just hospitalization and death,” said Akiko Iwasaki, Yale University immunology professor and a leader in long COVID research. “Even mild or asymptomatic infection can lead to long COVID. Tracking this on a national scale would be very informative.” 

Evidence for Vaccination and Long COVID

To-date, there are only two published sources on breakthrough cases and long COVID to support the theory that vaccinated people can develop long COVID. The first is a peer-reviewed study, published July 29 in the New England Journal of Medicine, involving 1,497 vaccinated healthcare workers in Israel. Of the 1,497 vaccinated, 39 had breakthrough infections, and of those 39, 19% reported fatigue, headaches, and muscle pain that lasted longer than six weeks. 

The second paper, published to the preprint server medRxiv on July 26 but not peer-reviewed, compiled the results of a social media poll posted to the Facebook group for Survivor Corps, a grassroots organization of COVID-19 survivors founded by Diana Berrent in 2020. Out of 1,949 respondents, 44 reported having a symptomatic COVID-19 infection post-vaccination. Of those, 24 reported symptoms of long COVID. One reported that their infection led to long COVID and hospitalization. “I’ll be the first to say this isn’t great data,” said Berrent of the informal nature of the poll, “but it’s an important signal that we need to do a better job of tracking these cases.”

Breakthrough infections are more frequent with the highly contagious delta variant, and a CDC report shows that vaccinated people can transmit it whether they develop symptoms themselves or not. “Vaccine-induced immunity is expected to clear most of the incoming virus and prevent viral spread to distal organs,” Iwasaki said. “I suspect that viral reservoirs will be unlikely to be established in a fully vaccinated person. However, if the virus triggers an autoimmune response, this will lead to long-term symptoms.”

A Massive Long COVID Research Effort

Much more rigorous research over a longer period of time is necessary before anything definitive can be said about long COVID with substantial evidence to back it up. The focus now is finding effective treatments for those who are experiencing both lingering COVID symptoms and new, unusual ones, said Walter Koroshetz, director of the National Institute of Neurological Disorders and Stroke, and co-leader of RECOVER, a massive National Institutes of Health initiative to study long COVID. The program is funded by a $1.15 billion grant set aside by Congress in December 2020. 

In order to devise effective treatments for long COVID, Koroshetz explained, researchers first have to identify its biological causes. Several hypotheses have already been proposed, three by Iwasaki: 

• The virus may persist in the body after the initial infection. 
• Lingering fragments like proteins and RNA may cause the symptoms. 
• An autoimmune response is triggered by the initial infection. 

To investigate these and other theories, RECOVER is tracking both people with new, acute COVID-19 infections, and those with long COVID. Autopsies and electronic health records also help inform scientists about long-term damage caused by these symptoms, as well as factors that affect recovery. The infrastructure is in place, but time is not on their side. 

“There is a growing number of patients who have survived COVID-19 only to develop long-term debilitating effects like severe fatigue and cognitive dysfunction, preventing them from resuming work and living normal lives,” Iwasaki lamented. “This is devastating millions of people around the world.”

*Tayag, J. (2021, Aug. 2). Can You Get Long Covid if You’re Vaccinated? Slate.

https://slate.com/technology/2021/08/long-covid-breakthrough-infection-vaccinated.html 

Much about the novel coronavirus, i.e., COVID-19, is still not fully understood. As research progresses and our knowledge of the virus increases, information can change rapidly. We strive to update all of our articles as quickly as possible, but there may occasionally be some lag between scientific developments and our revisions.