Clinics nationwide will begin giving vaccinations against monkeypox to people who may have been exposed to it.

People with a known exposure can now get immunizations.

The number of cases and the proportion of the state's population at risk for severe disease will be used to calculate the amount of vaccine given to the states.

State health authorities may ask for supplies of an older vaccine that is believed to protect against monkeypox.

The Department of Health and Human services will provide an additional 240,000 doses of the vaccine over the course of the next few weeks. More than 1.5 million doses will be available by the end of the year.

Rochelle Walensky is the director of the Centers for Disease Control and Prevention.

The ACAM2000 vaccine is associated with death in people who are immune compromised.

The vaccine plan was criticized by experts who said it was too small and slow to make a difference. The longer it takes to contain the monkeypox outbreak, the greater the chance that it will spread to men who have sex with men.

Dr. Gounder is an infectious disease expert and editor at large for public health at Kaiser Health News.

We will have a difficult time containing this if we don't start vaccinations more quickly. In order to reach men at high risk of contracting the monkeypox, tests and vaccines should have been offered at L.G.B.T.Q.

The plan was unfair to men with H.I.V., who will not have access to the Jynneos vaccine, according to some experts.

The National Coalition of STD Directors does not have enough to meet the needs. A strategy based on contacts with a positive case doesn't work well without better testing capacity.

It's not clear what qualifies as a probable exposure, and if you go to a rave, do you just say, "Oh, I went to a rave and I want to be safe?"

Many clinicians are concerned about the side effects of the older vaccine, as well as the misinformation and vaccine hesitancy they might fuel. She said that clinicians have said there is no way they would give someone ACAM2000.

The Jynneos vaccine has never been used on this scale, and federal health officials said they would be watching for side effects.

More than 9000 doses of Jynneos vaccine and 300 courses of antiviral treatments have been given to 32 countries by the administration.

The European Union is sending 5,300 of its 100,000 Jynneos doses to Spain which has the most cases. In July and August, other member states will get some of the vaccine.

There has been a rise in the number of monkeypox cases in Europe and the US.

There were more than 300 cases in 27 states and the District of Columbia by the end of June. The emergency operations center has been activated by the C.D.C.

According to the director of the Cornell Center for Pandemic Prevention and Response, the numbers are likely to be underestimated. He said that the epidemic is much larger than what the official case counts suggest.

The available doses are unlikely to be enough to meet the demand. The slots for the monkeypox vaccine were filled in less than 15 minutes.

As of Tuesday, 55 cases of monkeypox had been reported in New York City. affluent white men who have sex with men are the majority of the clientele at a single clinic in the city.

On June 23, the first dose was offered. The clinic was no longer able to accommodate walk-ins and had booked appointments through the end of June. The city was still waiting for more vaccine to arrive.

Keletso Makofane is a social network epidemiologist at the FXB Center for Health and Human Rights at Harvard University.

The uncertainty doesn't help cultivate the trust we need to have.

It would have been more equitable to offer the vaccines at the clinics frequented by Black men with H.I.V., according to several experts.