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Minnesota has reported 89 “breakthrough” cases in people who contracted the coronavirus after being fully vaccinated, according to the Star Tribune.
A small number of breakthrough cases can be expected because vaccines aren’t 100% effective, health officials said.
“We should not be fooled into seeing such a case as a reason to doubt the vaccine effectiveness,” Kris Ehresmann, MD, the director of infectious diseases for Minnesota, told the newspaper.
“Remember, a 95% effective vaccine still means we could expect to see infections in around 5 of every 100 people who get the vaccine,” she said.
As of Wednesday, more than 1.4 million people in Minnesota have received at least one COVID-19 vaccine. About 800,000 are considered fully vaccinated, which means it has been 14 days since their final dose and the vaccine has had time to spark an immune response. The 89 breakthrough cases represent less than a tenth of 1% of those who have been fully vaccinated.
Minnesota health officials are reviewing the breakthrough cases to determine if there are any similarities, Ehresmann said. If a cluster of cases stem from the same vaccine site, for instance, that could indicate whether a specific lot of vaccines had an issue or the site itself handled the doses incorrectly.
So far, state health officials have interviewed 72 of the 89 patients and found that 30 had COVID-19 symptoms. None of the breakthrough cases have led to death, and the patients tended to have mild illnesses.
“Yes, people get COVID, but people in general do overall better,” Andrew Olson, MD, the medical director of COVID-19 hospital medicine for M Health Fairview, told the newspaper. “We have seen that both in patients in our system who are hospitalized and patients who are not hospitalized.”
The CDC is tracking breakthrough cases across the country as more people get vaccinated, according to CNN. CDC officials are working with state health departments to look for any similarities that may indicate whether new coronavirus variants are evading the vaccines.
Throughout February and March, breakthrough cases were reported in Oregon, South Carolina, Florida, Texas, and Hawaii, according to The Atlantic. The CDC team will soon start reporting breakthrough case counts and any patterns related to the locations or people who contract COVID-19 after being fully vaccinated, a CDC spokesperson told the news outlet.
On Wednesday, state health officials in Idaho said they’ve identified “fewer than 100” breakthrough cases among the 250,000 people who have been fully vaccinated, according to KTVB 7.
Earlier this week, the Washington State Department of Health said it was working with the CDC to track breakthrough cases, according to KIRO 7 News.
“We know we will see breakthrough cases, it’s just what does the breakthrough case look like, who are they, where are they, and what vaccines — if any — show a higher rate of breakthrough,” Scott Lindquist, MD, the acting health officer for the health department, told the news outlet.
State health officials haven’t yet identified any breakthrough cases in Washington, but they’re surveilling for cases and conducting genomic sequencing to find variants.
“We actually are in discussion with the CDC about how many breakthrough cases should Washington be expecting because we know that vaccine isn’t 100%,” he said.