US President Joe Biden’s government has declared monkeypox a public health emergency.
The move came as nationwide cases topped 6,600, around a quarter of them from New York State.
The US has so far delivered some 600,000 vaccines, but this number is still far short of the approximately 1.6 million people considered at highest risk and who need the vaccine most.
The decision will speed up the distribution of vaccines, treatments and federal resources to curb the spread of the virus.
It comes less than a fortnight after the World Health Organization (WHO) issued its highest emergency alert following a worldwide surge in cases.
A quarter of these cases have appeared in the state of New York, which declared its own state of emergency over the disease last week.
The two states with the next highest caseloads – California and Illinois – declared states of emergency earlier this week.