U.S. Senators Susan Collins, R-Maine, and Richard Burr, R-North Carolina, wrote a letter to Centers for Disease Control Director Rochelle Walensky and Food and Drug Administration Acting Commissioner Janet Woodcock asking for more data on the effectiveness of the COVID-19 vaccines, particularly with respect to breakthrough cases.

The Senators acknowledged that the CDC has started to make some additional information available in tracking the rates of COVID-19 cases and deaths by vaccination status and vaccine product, according to an Oct. 20 news release.  However, they noted that data on hospitalizations by vaccine product remain unavailable to the public. In addition, they emphasized that only a handful of public health departments appear to be reporting information on breakthrough cases that result in hospitalizations or death to the CDC.

“We have heard from vaccinated health care professionals, seniors, and individuals who are immunocompromised or have certain chronic conditions who have questions about the data surrounding serious breakthrough infections and how the different vaccine products compare in protecting against hospitalizations and deaths,” the Senators wrote. “They also have questions about how these data have informed the recent FDA and CDC announcements on booster shots and how they will be taken into account on recommendations on the mixing and matching of vaccines.”

“At a time when there has already been public confusion on the decision making process around boosters, it is crucial that the CDC and FDA be trusted sources of accessible information on the efficacy of the three vaccines,” the Senators concluded. “The public would benefit from more robust data on which vaccine was received by fully vaccinated individuals who are hospitalized due to a breakthrough case, in addition to more data overall on breakthrough cases.”

The Senators asked CDC Director Walensky and FDA Acting Commissioner Woodcock:

• Do the CDC and FDA collect nationwide data on which vaccine was received by fully vaccinated individuals who nevertheless contract COVID-19 and are hospitalized?
• If not, what are the barriers to collecting and disseminating this information? 

• Are there limitations on the ability of the CDC and FDA to make such data publicly available?

• How are the CDC and FDA assessing trends in breakthrough infections and the variant or variants that are resulting in such breakthroughs?

Click HERE to read the full letter.