The 4 Things Everyone Should Know About Breakthrough COVID, CDC Says
The agency just updated its information on COVID cases after vaccination.
The COVID vaccine is relatively new, and so is our understanding of breakthrough infections, cases that happen in fully vaccinated individuals. As experts have learned more about breakthrough COVID, they've been able to assess the risks these cases may cause, along with the preventative measures people can take to keep themselves healthy. Now armed with more research, the Centers for Disease Control and Prevention (CDC) just updated its information on breakthrough COVID infections. Read on to find out the four things the agency wants you to know about COVID after vaccination.
Breakthrough infections are expected.
Since the beginning of the vaccine rollout, experts have repeatedly reminded the public that breakthrough infections are to be expected. Early on, during an April 12 press briefing, White House COVID adviser Anthony Fauci, MD, told the public that breakthrough infections occur "with all vaccines in clinical trials. And in the real world." He explained that "no vaccine is 100 percent efficacious or effective, which means that you will always see breakthrough infections regardless of the efficacy of your vaccine."
The CDC continues to emphasize this point in its recent update. "COVID-19 vaccines are effective at preventing most infections. However, like most vaccines, they are not 100 percent effective," the CDC notes. The agency also points out that as the number of people who are fully vaccinated increases, the number of breakthrough COVID infections will naturally rise with it.
Fully vaccinated people are less likely to develop severe illness from COVID.
While the COVID vaccines are effective at preventing transmission of the virus, their biggest strength remains in preventing severe illness. The CDC says that fully vaccinated people who end up developing COVID are much less likely to have that progress to severe illness than unvaccinated individuals. The agency also notes that the risk of getting infected in general is much higher for unvaccinated people. "Vaccines remain effective in protecting most people from COVID-19 infection and its complications," the CDC says. Earlier this month, data from the Kaiser Family Foundation showed that 1 in 900 people get COVID after being fully vaccinated, NBC reported.
Fully vaccinated people tend to have less severe symptoms.
In the CDC's update, the agency emphasized that while fully vaccinated people can still develop symptoms, they're often mild. "Even when fully vaccinated people develop symptoms, they tend to be less severe symptoms than in unvaccinated people," the CDC says. "This means they are much less likely to be hospitalized or die than people who are not vaccinated." According to data from the ZOE COVID Symptom Study in the U.K., the most common symptoms people who've been vaccinated experience include headache, runny nose, sneezing, sore throat, and a loss of smell.
While some vaccinated people experience mild symptoms, others may be completely asymptomatic. Devang Sanghavi, MD, of the Mayo Clinic, explained to the American Medical Association (AMA) that "because people who are vaccinated have had some immunity, some antibodies, a majority of these breakthrough cases are going to be asymptomatic."
Breakthrough infections can still be contagious.
While breakthrough COVID cases may not seem like a big deal when they come with a limited risk of hospitalization or severe symptoms, they can still be as contagious as any COVID case, experts now believe. The CDC update says that "people who get vaccine breakthrough infections can be contagious."
On July 30, the CDC published a study that demonstrated that people infected with the Delta variant, both with and without the vaccine, had similarly high viral loads. In a statement, CDC Director Rochelle Walensky, MD, explained that "high viral loads suggest an increased risk of transmission and raised concern that, unlike with other variants, vaccinated people infected with Delta can transmit the virus." She added that the discovery the study made was "concerning" and "pivotal" in the CDC's decision to begin recommending masks again.