Early data from various states shows that COVID-19 breakthrough cases are becoming more common than they were earlier this summer. Whether that's because of the ultra-contagious delta variant or because the populace is socializing more remains unclear.
While that doesn't mean vaccinated people aren't protected from the coronavirus — a large majority of hospitalizations and deaths are still among the unvaccinated — the realization that a vaccinated individual can still get and spread COVID-19 has left many among their ranks recalculating their own personal risks, especially in parts of the country where transmission rate are high.
Public health experts have special guidelines for those who contract a breakthrough COVID-19 case, meaning when a fully vaccinated person catches the coronavirus. According to the Centers for Disease Control and Prevention (CDC), when a vaccinated person tests positive they should self-isolate for 10 days. This means potentially missing work, school and other responsibilities.
In general, breakthrough cases are far less severe than "regular" COVID-19 cases that occur among the unvaccinated. In particular, those with breakthrough cases are far less likely to be hospitalized, although it does happen occasionally. Some counties, such as Douglas County in Oregon, actually track and report the vaccination status among their hospitalized COVID-19 patients; for instance, in their August 18, 2021 report, they noted that of 59 hospitalized COVID-19 patients, 51 were unvaccinated.
Still, the fear of contracting a breakthrough case is acute among many of the vaccinated, in part because of the risks of contracting COVID-19. Up to 10 percent of those who contract COVID-19 have long-term symptoms long after the virus has cleared their body, according to University of Alabama researchers. Patients have coined a term, "long Covid," to describe symptoms from a COVID-19 infection that last for more than one month.
People who experience long Covid sometimes refer to themselves as "long-haulers." Some long-haulers eventually experience full recoveries, while others do not. The long Covid symptoms patients report include (but aren't limited to) fatigue, brain fog, confusion, shortness of breath, headaches and chest pain. Notably, not everyone who became a long-hauler had a severe infection or was hospitalized after their COVID-19 diagnosis.
Doctors' current understanding of long Covid stems from pre-vaccine days. However, experts say it's likely a concern among the vaccinated who fear contracting COVID-19.
"I don't think we know that it does happen yet because we're still so early in the process of understanding what happens when people are infected despite vaccination," said Dr. Dave O'Connor, a professor of virology at the University of Wisconsin-Madison. "But biologically it's hard to think of reasons why it won't happen."
O'Connor said that's because in breakthrough infections — or what some infectious disease experts are now suggesting we call "infection despite vaccination" — high levels of viral genetic material appear in the upper respiratory tract. In fact, according to a study by scientists at the University of Oxford scientists, people who contract the delta variant after being fully vaccinated carry a similar amount of the coronavirus as those who are unvaccinated and get infected. What's a little less clear, O'Connor said, "is what's happening in the lower respiratory tract, or the lungs, and where most of the damage is being done by the virus."
However, O'Connor said if infections despite vaccination follow the same trajectory as unvaccinated infections, it is likely a proportion of these individuals will go on to develop long COVID.
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"But we don't know that yet, we simply don't have enough data from people who have had these infections despite vaccination," O'Connor said. "First, it'll probably come in anecdotes of people who were infected despite vaccination and then start reporting those long COVID symptoms — the fatigue, the brain fog, you know all the different constellation of symptoms that people have reported, and then eventually you'd expect this to be substantiated in larger cohort studies where researchers and doctors enroll individuals who self-report they're having these symptoms, and then look for commonalities between them."
Scientists like O'Connor don't have definitive data on long Covid and breakthrough cases because, as O'Connor said, the data is still sparse. One recent study published in the New England Journal of Medicine of Israeli healthcare workers showed the potential risk of long Covid after an infection despite vaccination: 39 people out of 1,497 fully vaccinated healthcare workers got COVID-19. While most of the cases were mild or asymptomatic, 19 percent had persistent symptoms of prolonged loss of smell, persistent cough, fatigue, weakness, muscle pain, or labored breathing.
Notably, the study is a small sample size. However, as O'Connor suspected, similar anecdotal evidence is surfacing in the United States.
Heather Bury is a 43-year-old woman living in the Southwest suburbs of Chicago who received the Johnson & Johnson vaccine on April 4, 2021. Nearly a month later, she struggled with her typical seasonal allergies — but one day, these allergies felt a bit off.
"I started to feel run down, foggy-brained, and there was a cough," Bury said. "Then right before I left work, the chest constriction started; I went to immediate care, where they prescribed an antibiotic, but strongly suggested I get a Covid test."
Bury tested positive for COVID-19 on May 7, 2021; afterward, her symptoms worsened. Bury told Salon she felt like an "elephant" was sitting on her chest. On May 10, she was admitted to the emergency room, where she was told she had COVID-19 pneumonia in both lungs. Bury was discharged a week later, but still has "so many crazy lingering conditions" nearly three months later. Brain fog, exhaustion, concentration issues, having trouble finding words, migraines — "the list really seems endless," Bury said.
Bury said her doctors have been extremely helpful during her recovery. But since she had a rare breakthrough case, she is "a trial and error patient," as she described herself.
"They had never dealt with somebody who has had the vaccine," Bury said. "They're trying to help you, but they don't know how to help you yet."
According to the CDC, 8,054 people have had a severe COVID-19 breakthrough case that led to hospitalization, out of the more than 166 million people who have been vaccinated. Notably, 25% of those hospitalizations were reported asymptomatic or not related to COVID-19.
As we know from COVID-19 cases in unvaccinated people though, it's not just those who have severe cases who experience long Covid. When asked what Dr. O'connor would tell people who are scared about the potential long-term effect of having long Covid after a breakthrough infection, O'Connor said, "I'm right there with them."
"I'm vaccinated, and I most certainly do not want to get a breakthrough infection," O'Connor said. "My concern isn't so much that I'm going to be hospitalized — it's that I'm worried that I would be in that sizable fraction of people who have long COVID symptoms."
O'Connor added that vaccinated people won't be living in uncertainty for too much longer.
"The truth is we just don't have enough data right now to have clarity on how often long Covid will occur, and whether it's going to be different in people who are previously vaccinated, compared to people who have not yet been vaccinated," O'Connor said. "I expect that we'll be getting more clarity on this over the next couple of months."
Correction: A previous version of this article stated 39% of vaccinated healthcare workers had breakthrough infections. This is incorrect. The study stated 39 people (out of 1,497) had breakthrough infections.