People can still get COVID and test positive after a booster shot, but they will likely have mild or no symptoms. However, the vaccine itself does not cause a positive test.
The vaccine
A booster dose of the COVID-19 vaccine
If a person contracts SARS-CoV-2 after getting the booster, they may test positive. However, they may have a very mild case of COVID-19 or even an asymptomatic infection.
Read on to learn about how the booster works and what it means if a person tests positive. We also explore the side effects of the booster and more.
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The booster significantly decreases a person’s chance of contracting the SARS-CoV-2 virus. Despite this, it is still possible to develop COVID-19 after the booster, so an individual may test positive.
According to a
Some common scenarios for testing positive after a booster include the following:
- A person might contract SARS-CoV-2 before the booster, then test positive a few days later.
- An individual might contract SARS-CoV-2 shortly after the booster but before the booster becomes fully effective.
- A person might contract SARS-CoV-2 even when fully boosted. In this scenario, the booster may still reduce the odds of severe illness. This is the main purpose of the booster.
The side effects of the COVID-19 booster are similar to those of the original COVID-19 vaccine side effects.
In 2021, the
Systemic symptoms, such as fever and headache, were also common, with 69.9% reporting at least one such reaction.
According to the
Rarely, a person may experience a severe allergic reaction. People with a history of severe allergic reactions to any component of the COVID-19 vaccine should not take the vaccine. However, there are very few medical reasons not to get the COVID-19 vaccine and boosters.
The newest COVID-19 booster provides protection against newer variants of SARS-CoV-2, including some types of Omicron. However, researchers do not have a precise figure on how long it offers protection.
Most research suggests that protection against disease declines fairly quickly, but protection against severe infection, hospitalization, and death lasts longer.
For example, a
The CDC gathered this data before the newer booster became available. This means the data for that booster may be different but are not yet available.
It is also important to note that the specific risk of disease, hospitalization, and other outcomes depend on many factors. A 2022 study using data from before the widespread dominance of Omicron found that fully vaccinated individuals who died from COVID-19 were more likely to be:
- older, with a median age of 82
- living in a long-term care facility
- experiencing at least one underlying medical condition associated with a higher risk of death
People
When a person gets a breakthrough infection, their symptoms are more likely to be mild and they are significantly less likely to become severely ill.
Sometimes, people test positive for COVID-19 after a booster and do not have symptoms. This is an asymptomatic infection. It may also be a presymptomatic infection, which is a positive test before symptoms begin.
People with an asymptomatic infection
The new bivalent booster offers protection against now dominant Omicron variants.
According to the
Even after having COVID-19, a person can still contract the virus. However, a vaccine offers additional protection.
It is still possible to test positive for COVID-19 after having a booster. This does not mean that the vaccine caused the positive test or did not work.
The main goal of the vaccines is to prevent severe disease, hospitalization, and death. These negative outcomes are very rare in fully vaccinated individuals.
People with questions about COVID-19 vaccines should consult a healthcare professional.