COVID breakthrough cases: What to know about symptoms, length, quarantine, long-term effects


The existing COVID-19 vaccines offer strong protection against hospitalization, severe illness and death.

They are not 100% effective against preventing COVID-19 infection, though. These cases are called “breakthrough infections” where fully vaccinated people come down, in most instances, with a less severe form of the virus.

Here is what you need to know.

According to the ZOE COVID Symptom Study, the top five symptoms of a breakthrough case include the following:

  • Headache
  • Runny nose
  • Sneezing
  • Sore throat
  • Loss of smell

Medical experts say it is not unusual for a person to feel breakthrough COVID-19 symptoms for several weeks, but at the same time, the worst symptoms such as a headache or cough could clear up in two weeks or less, according to Roll Call.

The CDC says people who are vaccinated and test positive should quarantine, or isolate, for 10 days. Once those 10 days are up, the person is no longer contagious provided they were not severely ill, they are fever-free for at least 24 hours, and any remaining symptoms are improving (not including loss of smell and taste).

According to NPR, a small Israeli study found that breakthrough infections could contribute to long COVID symptoms.

The study followed 1,500 fully vaccinated health care workers. Out of those, 39 contracted a breakthrough infection, and seven reported long COVID symptoms that lasted more than six weeks, the study showed.

So yes, you can be at risk for long COVID if you catch a breakthrough infection. But it is rare for a fully vaccinated person.

Related stories about COVID-19:

How to get a COVID booster shot at CVS or Walgreens

These are the people eligible for a COVID booster shot, according to the CDC

The side effects to look out for if you get a COVID booster shot

What are the most common side effects from the Pfizer COVID booster shot?

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