Three of four people whose deaths were previously identified as possible “breakthrough” cases — where a person contracts COVID-19 after being fully vaccinated — had actually contracted the coronavirus before getting the injections, state health officials have concluded.
The deaths were among cases identified during weekly reviews by the Michigan Department of Health and Human Services, when data on confirmed and possible cases of COVID-19 are compared with vaccination data.
No vaccine is 100% effective, and public health officials conduct the reviews to track the effective of the COVID-19 vaccines. Positive tests that occur 14 or more days after a person completes vaccination are flagged as possible “breakthrough” cases.
MDHHS announced April 5 that 246 such cases had been identified, including three people who died. The review included cases that were reported between Jan. 1 and March 31.
All three of the potential breakthrough cases had a prior positive PCR test for COVID-19, but met the definition of a “breakthrough” case because they’d tested positive more than 45 days before the onset of symptoms, said Chelsea Wuth, a spokeswoman for the Michigan Department of Health and Human Services.
“It is likely that these three cases were examples of prolonged viral shedding of SARS-CoV-2 virus rather than reinfections with COVID-19,” Wuth said in an email to The News on Sunday.
Additional reviews have brought the numbers to 334 possible breakthrough cases through April 6, with four deaths, according to Wuth. The fourth death is still under active review by the local health department, so additional information is not yet available, she added.
“Some of these individuals may ultimately be excluded from this list due to continuing to test positive from a recent infection prior to being fully vaccinated,” Wuth added.
Wuth noted that as of April 6 more than 1.8 million Michigan residents had completed their COVID-19 vaccination, meaning they received both injections of the two-shot Pfizer or Moderna vaccine, or an injection of the one-dose Johnson & Johnson vaccine.
“We expect to see breakthrough cases with any vaccination, including all the COVID-19 vaccines,” Wuth said. “The number of potential cases identified to date is not in excess of what might be expected with vaccines with 95% efficacy.
“Studies indicate that even if vaccinated people do become ill, they are far less likely to experience severe illness requiring hospitalization or resulting in death.”
kbouffard@detroitnews.com
Twitter: @kbouffardDN