The Department of Health and Human Services will cancel contracts and pull funding for some vaccines that are being developed to fight respiratory viruses like COVID-19 and the flu, Associated Press reported.

Robert F. Kennedy Jr. announced in a statement Tuesday that 22 projects, totaling $500 million, to develop vaccines using mRNA technology will be halted.

Kennedy’s decision to terminate the projects is the latest in a string of decisions that have put the longtime vaccine critic’s doubts about shots into full effect at the nation’s health department. Kennedy has pulled back recommendations around the COVID-19 shots, fired the panel that makes vaccine recommendations, and refused to offer a vigorous endorsement of vaccinations as a measles outbreak worsened, according to Associated Press.