What is a ‘breakthrough infection’ and what are the odds it happens to you?

breakthrough infections
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Three vaccines have been approved by the Food and Drug Administration for use in the United States. All of them are immensely effective at protecting against infection, severe illness, and hospitalization, but none offer 100% protection. This has allowed for cases of “breakthrough infection,” or infection occurring even after full vaccination.

Instances of a breakthrough infection are extremely rare, however, and the chances of it happening to you are very slim.

Experts say instances of breakthrough infection are to be expected. As noted by Dr. Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, there is no cause for concern regarding breakthrough cases. “There’s nothing there yet that’s a red flag,” he said.

The Centers for Disease Control and Prevention has been tracking cases of breakthrough infection for months. Out of 45 states and territories and 87 million fully vaccinated American adults, just over 7,100 instances of breakthrough infection were reported. That is approximately 0.008%.

Of the tracked instances of breakthrough cases, 64% were women and 46% were over the age of 60. One out of three experienced asymptomatic infections. Seven percent of the tracked cases occurred in already-hospitalized patients, and 1% died. Notably, not all of the cases of hospitalization and death were due to COVID-19.

As noted by the Washington Post, there are likely breakthrough infections that have not been tracked. Particularly after full vaccination, people are far more likely to ignore some of the minor warning signs of COVID-19, like fatigue, shortness of breath, or fever. If they don’t get tested for COVID-19, their data does not contribute to the research, making it harder to track precisely how many instances of breakthrough cases have really occurred. 

Despite the likely higher-than-reported numbers, the chances of experiencing a dangerous breakthrough infection are extremely slim. There are no unexpected patterns in the instances that have cropped up thus far, but experts are advising people to remain vigilant. Even after getting fully vaccinated, it is prudent to continue wearing a mask in public areas and practicing diligent hygiene, at least until the U.S. has reached a level of herd immunity.

Sources: Washington Post, CDC, Forbes

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