U.S. Health Secretary Robert F. Kennedy Jr. said the organization has “ignored the science" and “lost the public trust.”

Kennedy called on Gavi “to re-earn the public trust and to justify the $8 billion America has provided in funding since 2001,” saying officials must “consider the best science available, even when that science contradicts established paradigms.” Kennedy said until that happens, the U.S. won’t contribute further to Gavi.

The Gates Foundation said on Tuesday it will commit $1.6 billion over the next five years to support Gavi, a public-private partnership that helps buy vaccines for the world's poorest children. The number of kids dying around the world will likely go up this year because of the massive cuts to foreign aid,