Monkeypox vaccines will be made available at Gay Pride and other events as part of a new pilot program to stem the fast spread of the virus, US health authorities said Thursday.

US cases have quickly soared to 13,500 since May, when the current outbreak began in Europe. Latest official data shows 98 percent of cases have been among men, and 93 percent among men reporting recent sexual contact with other men.

Hispanic and Black people are both disproportionately impacted.

The federal government "is launching a pilot program that will provide up to 50,000 doses from the national stockpile to be made available for Pride and other events," White House monkeypox response coordinator Bob Fenton told reporters.

Notable upcoming events include Black Pride in Atlanta and Southern Decadence in New Orleans, both around Labor Day on September 5 and the preceding weekend.

The reopening of colleges this fall is also expected to accelerate the spread.

State health departments can put in orders based on the size of the event and its ability to reach attendees at highest risk, added Centers for Disease Control and Prevention (CDC) director Rochelle Walenksy.

But she added that since the Jynneos monkeypox vaccine comes in two doses, recipients will be advised that they won't receive instant protection at the event itself and must follow up on their second shot.

Overall, the US has delivered around one million vaccine doses to state and other local jurisdictions, and will start to make available for order an additional 1.8 million doses from next week, said Fenton.

The federal government will also be sending out 50,000 courses of antiviral treatment TPOXX.

Last week, the Food and Drug Administration authorized a new procedure for injecting the vaccine -- in between the upper layers of the skin rather than deeper, beneath it -- to get five times more out of the same amount of substance.