Press Releases

05/07/2021

CTDPH Releases Data on Covid-19 Vaccine Breakthrough Cases, Highlighting the Vaccine’s Effectiveness Against the Virus

Cases of fully vaccinated residents contracting virus “very rare”

As Connecticut surpasses the 50% mark for Connecticut residents ages 16 and over who are now fully vaccinated, the Department of Public Health today released data on vaccine breakthrough cases, which clearly show that the COVID-19 vaccines are highly effective at fighting the virus.  So-called “vaccine breakthrough cases” occur when a person who has completed their vaccine series becomes infected with the COVID virus.  The data show that cases of COVID-19 in fully vaccinated individuals are rare, with less than 0.1 percent of Connecticut’s fully vaccinated persons reported to DPH as having contracted the virus.

Of the 1,467,189 persons who have completed their vaccine series, 242 have been confirmed as contracting COVID-19.  Of those, 109 (45%) had no symptoms of the disease.  

Three deaths have occurred among the 242 vaccine breakthrough cases.  All three individuals were confirmed to have had underlying medical conditions and were in the following age groups:  55-64 (1), 65-74 (1), and 75+ (1).  Nationally, the CDC has reported a total of 132 vaccine breakthrough deaths.

“The main takeaway is that COVID-19 vaccines are highly effective and cases of infection after a person is fully vaccinated are very rare.  The best protection against severe illness, hospitalization and death from COVID-19 is vaccination, and I strongly urge all eligible Connecticut residents who have not yet gotten vaccinated to do so,” said Acting DPH Commissioner Dr. Deidre Gifford.

In addition to the overall number of breakthrough cases, DPH also announced that of the 242 breakthrough cases:

  •  159 (65.7%) cases were among women
  •  58 (24%) cases occurred among persons living in congregate settings (i.e. – nursing homes, assisted living facilities)
  •  32 (13.2%) cases have been hospitalized

“The vaccine is our most powerful tool against COVID-19, but these rare instances of infection after vaccination are a reminder that no vaccine is 100% effective. As long as we continue to see cases of COVID in Connecticut, it is important  to continue the use of the other tools at our disposal:  masking when indoors and in large outdoor crowds, hand washing, social distancing, and limiting gathering sizes when vaccination status is unknown,” added Acting Commissioner Gifford.