State reports less than .1 percent COVID-19 breakthrough cases


TRENTON- more than 1,000 fully vaccinated individuals have contracted COVID-19, known as breakthrough cases, according to the New Jersey Department of Health Commissioner, claiming the metric is proof that the three federally approved vaccines are working. 

That would mean that of the 4.4 million individuals in New Jersey who are fully vaccinated, much less than one percent have gone on to catch the virus. According to Judith Persichilli, commissioner of the New Jersey Department of Health, her agency will continue to investigate breakthrough cases. 

“No vaccines are a hundred percent effective against any illness, so some cases among fully vaccinated individuals are expected,” Commissioner Persichilli said, going on to say that all three vaccines available in the United States are “extremely effective.”


Between Dec. 15 and April 23, 1,319 breakthrough cases were identified by state officials. That total represents .06 percent of fully vaccinated individuals. 

“This high percentage demonstrates that breakthrough infections are extremely,” rare she said, adding that those who go on to contract COVID-19 experience less serve illness. 

Of the total number of breakthrough cases, 92 individuals were later hospitalized, with only 30 being hospitalized for reasons related to COVID-19. The commissioner also reported that 14 breakthrough cases ended in mortality, with seven reported to be related to COVID-19.  

“While vaccine breakthrough cases were seen in all eligible age groups, hospitalizations and deaths were only seen in those over the age of 50,” Dr. Edward Lifshitz, medical director of the New Jersey Department of Health Communicable Disease Service, adding that those over the age of 80, he added, accounted for half of the breakthrough hospitalizations and half of the deaths. 

“Because people with no or mild symptoms are unlikely to be tested for COVID-19, we know that this data … represents an undercount of these individuals,” he said. 

The Centers for Disease Control and Prevention [CDC] report that mRNA vaccines, developed by Pfizer/BioNTech and Moderna, are 94 percent effective against the virus.

The single-dose Janssen vaccine, developed by Johnson & Johnson, has been reported by the CDC to be 66.3 percent effective at preventing COVID-19.