What is a COVID-19 vaccine ‘breakthrough’ case?

What is a COVID-19 vaccine “breakthrough” case?

It’s when a fully vaccinated person gets infected with the coronavirus. A small number of such cases are expected and health officials say they’re not a cause for alarm.

COVID-19 vaccines work by teaching the body to recognize the virus. So if you’re exposed to it after vaccination, your immune system should be ready to spring into action and fight it.

In studies, the two-dose COVID-19 vaccines by Pfizer and Moderna were around 95% effective at preventing illness, while the one-shot Johnson & Johnson shot was 72% effective, though direct comparisons are difficult. So while the vaccines are very good at protecting us from the virus, it’s still possible to get infected with mild or no symptoms, or even to get sick.

If you do end up getting sick despite vaccination, experts say the shots are very good at reducing the severity of the illness — the main reason to get vaccinated.

Most people with breakthrough infections experience mild illness, said Dr. William Moss, a vaccine expert at the Johns Hopkins Bloomberg School of Public Health.

In the U.S., people who weren’t vaccinated make up nearly all hospitalizations and deaths from COVID-19.

It’s difficult to determine why any particular breakthrough case happens. How much of the virus you’re exposed to could be a factor, Moss said. Our individual immune systems will also affect how well we respond to the shots. Some people, for example, have health conditions or take medications that could make their immune systems less responsive to the vaccines.

People might also have been exposed to the virus before the shots took full effect. Though less likely, they may have received a dose that was improperly stored or administered, Moss said.

The Centers for Disease Control and Prevention notes variants could be factors in some breakthrough cases, though evidence so far indicates the vaccines used in the U.S. are protective against them.

Health officials are also watching for signs that breakthrough cases are rising, which could signal that protection from the vaccines is fading and boosters are needed.

___

The AP is answering your questions about the coronavirus in this series. Submit them at: FactCheck@AP.org. Read more here:

What should I know about the delta variant?

Will one dose of a two-dose COVID-19 vaccine protect me?

Can you mix and match COVID-19 vaccines?

Do I need to get tested for COVID-19 if I’m vaccinated?

Share Your Story

Nativo Sponsored Content

Ad Tango


"

taboola desktop

MORE ARTICLES LIKE THIS

1
Irrigation innovation: Drought challenges water traditions in New Mexico
ABQnews Seeker
Drought tests centuries-old water traditions in ... Drought tests centuries-old water traditions in New Mexico
2
New Mexico backs Texas in opposing nuclear fuel storage
ABQnews Seeker
Holtec facility seeking approval Holtec facility seeking approval
3
BLM moving back to DC, reversing Trump-era decision
ABQnews Seeker
  WASHINGTON -- Interior Secretary Deb ...   WASHINGTON -- Interior Secretary Deb Haaland is moving the national headquarters of the Bureau of Land Management back to the nation's capital after ...
4
Santa Fe mayor suffers setback
ABQnews Seeker
Ethics board dismisses effort to force ... Ethics board dismisses effort to force critics to disclose finances
5
In New Mexico, rules on COVID school closures vary
ABQnews Seeker
SANTA FE – State ... SANTA FE – State education officials largely ceded control over if and when schools need to ...
6
Judge OKs trial evidence in Farmington-area woman's death
ABQnews Seeker
Airman accused of Mennonite Sunday school ... Airman accused of Mennonite Sunday school teacher's slaying
7
9/11 survivors still bear scars, relive the trauma
ABQnews Seeker
'It never goes away, for those ... 'It never goes away, for those of us that were there that day'
8
Plan hints at solving NM education inadequacies
ABQnews Seeker
Draft offers few specific proposals Draft offers few specific proposals
9
US drone destroys vehicle transferring IS suicide bombers
ABQnews Seeker
Afghan official: Three children were killed ... Afghan official: Three children were killed in building next to target