This is a question many have been asking since the first report of major infections: Can you still transmit the virus if you are vaccinated and infected?
The answer is believed to be yes, but Chicago’s top doctor said evidence suggests fully vaccinated people have a smaller window to spread it.
“So the vaccine doesn’t stop transmission 100% and it never has,” said Dr. Allison Arwady, commissioner of the Chicago Department of Public Health. “But it is the most important thing that lowers your risk of contracting COVID … You cannot spread COVID if you are not infected with COVID. Could even potentially spread COVID is less than for them. unvaccinated persons. ”
NBC News reported earlier this month that a new study found that fully vaccinated people were less likely to spread the virus even if they were infected, a particularly interesting finding as officials investigate the spread of the variant. delta and how vaccination can reduce transmission.
The study, conducted by British scientists at the University of Oxford, reportedly examined the records of nearly 150,000 contacts traced from around 100,000 coronavirus cases. including people fully or partially vaccinated with Pfizer-BioNTech or AstraZeneca vaccines, as well as unvaccinated people. The researchers then looked at how vaccines affected the spread of the virus if a person had a breakthrough infection with the highly contagious alpha variant or delta variant.
According to the CDC, studies conducted before the emergence of the delta variant found that people vaccinated with COVID mRNA vaccines who develop a breakthrough infection “generally have a lower viral load than unvaccinated people.”
“This observation may indicate reduced transmissibility, as viral load has been identified as a key factor in transmission,” the agency reported, noting that further study was needed.
For the Delta variant, early data indicated that vaccinated and unvaccinated people infected with Delta had similar levels of viral RNA and cultivable virus detected, but some studies have shown “a more rapid decline in viral RNA and virus. virus that can be cultivated in fully vaccinated people, “according to the CDC.
“These results (…) suggest that any risk of associated transmission is significantly reduced in those vaccinated,” the CDC said. “Even for the delta, the evidence suggests that fully vaccinated people who are infected are infectious for shorter periods than unvaccinated people infected with the delta.”
Although rare, breakthrough infections continue to be reported in Illinois and across the country, although experts note that most people who are fully vaccinated and contract COVID have had mild infections, if any. symptom, and rarely require hospitalization or die.
In Illinois, 2,297 fully vaccinated people have been hospitalized since January with a breakthrough infection, representing 0.032% of the state’s fully vaccinated population. At the same time, 679 have died.
The Illinois Department of Public Health reported that among those hospitalized or deceased, more than half had underlying health issues.
According to data from Chicago, unvaccinated residents are more than twice as likely to contract COVID as fully vaccinated residents.
Arwady said that although no vaccine “100% stops COVID”, vaccination and masking remain the most effective prevention tools.
His comments come as health officials debate the need for booster shots for millions of Americans.
Last month, the FDA cleared booster shots of Pfizer’s vaccine for older Americans and other groups with increased vulnerability to COVID-19.
This week, a panel of external FDA experts is reviewing the data to determine whether it will recommend authorization of the booster doses of Moderna and Johnson & Johnson. This is the first step in a review process that also includes approval from the leadership of the FDA and the Centers for Disease Control and Prevention.
An estimated 103 million Americans are fully vaccinated with Pfizer’s formula, 69 million with Moderna and 15 million with J&J, according to the CDC.
Scientists pointed out that the three vaccines used in the United States still offer strong protection against serious illness and death from COVID-19. The problem now is how quickly and to what extent the protection against a milder infection can decrease.