Letter to Dr. Rochelle Walensky, Director of the Centers for Disease Control and Prevention, and Dr. Janet Woodcock, Acting Commissioner of the Food and Drug Administration - Senators Collins, Burr Press CDC, FDA on Insufficient Data on Efficacy of COVID-19 Vaccines, Breakthrough Cases

Letter

Dear Director Walensky and Acting Commissioner Woodcock:

Vaccines have helped to prevent hospitalizations and deaths from COVID-19, a fact that is made
more clear by the high rates of hospitalization and death among unvaccinated
individuals. Nevertheless, as the sad death of Secretary of State Colin Powell reminds us,
breakthrough cases of COVID can and do occur even among the fully vaccinated, and those who
are immunocompromised are particularly at risk. 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.

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. 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.

We appreciate that the CDC has started to make some additional information available on
vaccine effectiveness, particularly in tracking the rates of COVID-19 cases and deaths by
vaccination status and vaccine product. Data on hospitalizations by vaccine product, however,
are not publicly available at this time. Another limitation is that only a handful of public health
departments appear to be reporting information on breakthrough cases that result in
hospitalization or death to the CDC. Separately, CDC's COVID-NET provides information on
hospitalizations of patients with breakthrough cases, but it does not provide that information by
vaccine product and there appears to be a significant lag in making such data publicly available.
Again, only a limited number of states are reporting into this system.

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. 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 vital
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?

Please provide your responses in advance of the next scheduled hearing of the federal COVID
task force before the Senate Health, Education, Labor, and Pensions Committee. Thank you for
your prompt response and attention to these important questions.

Source