The CDC tracked all breakthrough cases until the end of April, then abruptly stopped without making a formal announcement. A reference to the policy switch appeared on the agency’s website in May about
halfway down the homepage.
“I was shocked,” said Dr. Leana Wen, a physician and visiting professor of health policy and management at George Washington University. “I have yet to hear a coherent explanation of why they stopped tracking this information.”
The CDC said in an emailed statement to ProPublica that it decided to focus on the most serious cases because officials believed more targeted data collection would better inform “response research, decisions, and policy.”
Sen. Edward Markey, D-Mass., became alarmed after the Provincetown outbreak and wrote to CDC director Dr. Rochelle Walensky on July 22, questioning the decision to limit investigation of breakthrough cases. He asked what type of data was being compiled and how it would be shared publicly.
“The American public must be informed of the continued risk posed by COVID-19 and variants, and public health and medical officials, as well as health care providers, must have robust data and information to guide their decisions on public health measures,”
the letter said.
Markey asked the agency to respond by Aug. 12. So far the senator has received no reply, and the CDC did not answer ProPublica’s question about it.