The United States used to be a leader in vaccine research, development and policymaking. Now the US Secretary of Health, Robert F Kennedy Jr, is undermining the country’s vaccine program at the highest level and supercharging vaccine scepticism.

Two weeks ago, Mr Kennedy sacked the entire Advisory Committee on Immunization Practices responsible for reviewing the latest scientific evidence on vaccines. He alleged conflicts of interest and handpicked a replacement panel.

On Wednesday, he announced the US would stop funding the global vaccine alliance, Gavi, because he claimed that “when the science was inconvenient today, Gavi ignored the science”.

Mr Kennedy questioned the safety of COVID vaccines for pregnant women, as well as the diphtheria, tetanus and pertussis vaccine.