COVID-19 vaccines are the best way to protect people from getting seriously ill with the virus, as well as stave off extended hospital stays and death, according to the Centers for Disease Control and Prevention.
However, no vaccine is 100% effective and, though rare, fully vaccinated people can contract coronavirus. These cases, known as breakthrough infections, can cause COVID-like symptoms — or no symptoms at all.
Researchers behind the ZOE COVID Symptom Study found that the five most common symptoms reported by those vaccinated against the virus are:
Loss of smell
The study, which looks at COVID-19 symptoms and tracks the virus’s spread, is the brainchild of doctors and scientists at Massachusetts General Hospital, the Harvard T.H. Chan School of Public Health, King’s College London and the Stanford University School of Medicine, according to its website.
Researchers also teamed with health science firm ZOE for the report.
The study found that vaccinated individuals experienced COVID-19 symptoms similar to those reported by people who had or had not gotten the shot. Those with the vaccine had fewer symptoms in a shorter time frame, however, “suggesting that they were falling less seriously ill and getting better more quickly,” researchers wrote.
The report also found that some symptoms — including persistent cough — were more likely to show up in people who received just one dose of the two-shot Pfizer or Moderna vaccines or hadn’t been vaccinated at all.
“Curiously, we noticed 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,” study authors wrote. “If you’ve been vaccinated and start sneezing a lot without an explanation, you should get a COVID test.”
Sneezing isn’t among the COVID-19 symptoms noted by the CDC, but the updated list includes fever or chills, cough, fatigue, new loss of taste or smell and a sore throat. Symptoms usually appear two to 14 days after exposure, the public health agency said, and can be mild or severe.
Asymptomatic cases are also possible among those who are fully vaccinated, meaning there’s a small chance they can spread the virus to others.
While breakthrough infections are uncommon, vaccinated people should still watch for possible COVID-19 symptoms, the CDC said.