Breakthrough COVID Infections: Are we more at risk than we think?
Breakthrough infections, defined as a case of COVID in a vaccinated individual, are occurring across America. In fact, the highly contagious Delta variant (lineage B.1.617.2) is now being documented as the cause of over 80% of new COVID cases in the U.S.
As testing continues to soar and cases continue to surge, research reveals that vaccinated individuals can transmit COVID with or without symptoms of infection. On May 1st, the CDC decided to stop tracking breakthrough infections among vaccinated adults unless they lead to hospitalization or death. Breakthrough infections are expected with any vaccine, but the scientific community is urging the CDC to reconsider how they track breakthrough infections of COVID Delta. The question: Shouldn’t those vaccinated know what the breakthrough rate is, what age groups may be most susceptible and what zip codes are affected by these breakthrough cases?
The Issue
Without knowing the true rate of infection in vaccinated persons, Americans have little information to calculate their own risk tolerance. In other words, if vaccinated Americans are getting COVID at a rate of 1% or 30% or 50% among all cases, this would be helpful in allowing people to decide how they will behave. Before the Delta surge, many of us believed a vaccination was all we needed to avoid COVID. This has now changed and knowing the true rate of infection is imperative.
NBC Chicago reported almost a month ago on July 19th (link) that at least 151 Illinois residents died due to breakthrough infections, while more than 500 were hospitalized. But as for asymptomatic or mild symptomatic cases, the true numbers are a mystery.
When asked by the Center for Illinois Politics if they were recording all breakthrough cases, Melaney Arnold from the Illinois Department of Public Health (IDPH) stated:
“Following CDC, IDPH is reporting only patients with COVID vaccine breakthrough infection that were hospitalized or died to help maximize the quality of the data collected on cases of greatest clinical and public health importance. Breakthrough hospitalization and breakthrough death data go back to January 2021. Breakthrough is defined as an individual who tests positive for COVID at least 14 days after being fully vaccinated and did not test positive in the previous 45 days.”
The rapidly spreading COVID Delta variant has led many Illinois residents to question the risks of infection for those already vaccinated. The answer? It may not be as clear as you think. Keep reading to learn about how Illinois handles COVID-19 Delta and what you can expect from the CDC response.
FAQs
- Why did the CDC decide on May 1 to stop reporting COVID infections that don’t require hospitalization among vaccinated people?
The CDC released a statement on its website stating that it will no longer report on COVID infections that don’t require hospitalizations or death, which “will help maximize the quality of the data collected on cases of the greatest clinical and public health importance.”
- Are some counties providing this information?
Due to CDC guidelines, there are no counties in Illinois currently providing information beyond what is required regarding hospitalization or death in the case of breakthrough infections.
- Are breakthrough cases listed on the IL Dept. of Public Health (IDPH) website?
Only the breakthrough cases that resulted in hospitalization or death are listed on the state’s Department of Health dashboard.
- Can vaccinated people transmit COVID?
Yes, vaccinated people with breakthrough infections can transmit COVID.
- I keep hearing about mild breakthrough cases among vaccinated people, but the numbers appear higher than what I read in the news. Why would that be?
The CDC decided to stop tracking every breakthrough case in the U.S. on May 1, unless cases lead to hospitalization or death.
Messaging seems to encourage vaccination, but does not provide data to help vaccinated people make educated choices to protect themselves and others.
Breakthrough infections are, on average, significantly less detrimental. It is important to remember that although you may be vaccinated, you can carry and spread the COVID virus to others, including those who may be immune-compromised and cannot be vaccinated themselves.
The best way vaccinated people can protect themselves and others is to wear a mask, social distance, and limit social interactions in public spaces.
Just published in New York Magazine, 8/12/21:
https://nymag.com/intelligencer/2021/08/breakthrough-covid-19-cases-may-be-a-bigger-problem.html
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