Despite the uncertainties, German Minister of Health Karl Lauterbach acknowledged in March that though rare, Long Covid–like symptoms after vaccination are a real phenomenon. He said his ministry was working to organize funding for studies, although none has been announced so far.
Researchers studying these complications also worry about undermining trust in COVID-19 vaccines. Harlan Krumholz, a cardiologist at Yale University, says concern that the antivaccine movement would seize on any research findings made him hesitant at first to dive in. But about a year ago he and Yale immunologist Akiko Iwasaki began to welcome postvaccination patients into a new study called LISTEN that also includes Long Covid patients. Among other things, it aims to correlate symptoms with immune cell patterns in blood samples.