WHO’s constitution, drafted in New York, doesn’t have a clear exit method for member states. A joint resolution by Congress in 1948 outlined that the U.S. can withdraw with one year's notice. This is contingent, however, on ensuring that its financial obligations to WHO “shall be met in full for the organization’s current fiscal year.”

Of the many, one of Trump's campaign promise was to reject global institutions, which is why the health experts are worrying that it could isolate the US with consequences for pandemic and disease response and diplomatic relations worldwide.

President Donald Trump’s day one order withdrawing the United States from the World Health Organization as he signed a flurry of new executive actions Monday night is a major hit to the nation’s public health system,