Being fully vaccinated against COVID has many of us breathing easy, confident that we are highly protected from severe infection and hospitalization with the virus. But breakthrough cases, while rare, are still possible, and though these cases are often asymptomatic, that's not always the case. In fact, new data shows that many fully vaccinated people who get COVID do experience symptoms, just not necessarily the ones that you'd expect.
At this point, you're probably well aware of the notable COVID symptoms. The Centers for Disease Control and Prevention (CDC) has a full list, including fever or chills, cough, shortness of breath, fatigue, and muscle aches. But while these symptoms are certainly still possible, they're not necessarily the most common signs of COVID currently. And that's especially true when it comes to breakthrough COVID cases, which tend to have milder symptoms for a shorter period of time.
The ZOE COVID Symptom study has been tracking the shifting signs of the virus over time. Based on reports from people infected with COVID, these are the top five most common symptoms among fully vaccinated people: headache, runny nose, sneezing, sore throat, and loss of smell. While this list was first published in late June, CNBC reports that these remain the most common symptoms reported, per the ZOE COVID Symptom study.
While some of these symptoms are consistent for people at all vaccination levels, the study shows that many of the previously dominant COVID signs are more likely to appear for unvaccinated people. Notably, a persistent cough is only in the top five COVID symptoms for people who have not been vaccinated or received just one shot. Meanwhile, a fever—once considered one of the primary indicators of a COVID infection—appears in the top five only for unvaccinated people. For fully vaccinated people, fever is now the 12th most common symptom, making it rather unlikely.
Sneezing is perhaps the most surprising symptom on the list, and the only new COVID symptom not included on the CDC website. It's also notably only in the top five for people who have been partially or fully vaccinated. As the ZOE COVID Symptom study notes, "Our data shows that people who had been vaccinated and then tested positive for COVID-19 were more likely to report sneezing as a symptom compared with those without a jab. This suggests that sneezing a lot with no explanation after you've been vaccinated could be a sign of COVID-19."
That doesn't mean, of course, that sneezing is immediately a reason to panic. The researchers are also quick to explain that sneezing is a common and benign symptom of hay fever, which many people experience during warmer weather. However, frequent and sudden sneezing could be cause for concern, especially if you have any of the other most common breakthrough COVID symptoms.
And it's important to remember that breakthrough COVID cases are rare. The Pfizer and Moderna vaccines are both close to 95 percent effective at preventing symptomatic infection, while the Johnson&Johnson vaccine is around 66 percent effective. At the same time, it's better to be safe than sorry, which is why the researchers ultimately suggest, "If you've been vaccinated and start sneezing a lot without an explanation, you should stay home and get a COVID test, especially if you're living or working around people who are at greater risk from the disease."