Following growing activist pressure and criticism, the Biden administration on Thursday declared monkeypox a national public health emergency, a move that empowers federal agencies to better direct resources toward combating an outbreak that’s infected thousands of Americans.

Speaking to reporters at an afternoon press briefing, U.S. Health and Human Services Secretary Xavier Becerra said the administration is “prepared to take our response to the next level in addressing this virus, and we urge every American to take monkeypox seriously.”

The administration’s move follows a July 23 World Health Organization global health emergency declaration and similar designations by U.S. states, counties, and cities including California, Illinois, New York, New York City, Los Angeles, San Diego, and San Francisco.

Thanking the Biden administration “for taking this critical step to fight monkeypox,” Democratic New York Gov. Kathy Hochul said that “this will allow us to respond even more aggressively by increasing our testing, treatment, and vaccination efforts.”

Infectious disease experts and activists have criticized what they say is the federal government’s lack of urgency in responding to monkeypox, which has infected more than 6,600 people in the United States as of Wednesday, according to the U.S. Centers for Disease Control and Prevention. The Biden administration has come under fire for waiting more than three weeks after the first confirmed U.S. monkeypox cases before moving to procure vaccine stocks.

The New York Times reported Wednesday:

The government is now distributing about 1.1 million doses, less than a third of the 3.5 million that health officials now estimate are needed to fight the outbreak. It does not expect the next delivery, of half a million doses, until October. Most of the other 5.5 million doses the United States has ordered are not scheduled to be delivered until next year.

“What I expected to see would have been a more vigorous kind of a response based on lessons that we’ve learned from… Covid-19, as well as lessons we’ve learned from the HIV response,” Dr. Wafaa El-Sadr, founder and director of the International Center for AIDS Care and Treatment Program at Columbia University Mailman School of Public Health, told Voice of America.

“When you have an outbreak, the most important thing is you have to act fast, you have to mobilize,” he added, “and you have to rally all your assets to work together really quickly to be able to do what’s needed.”

Following the lead of public health advocates, U.S. Sen. Kirsten Gillibrand (D-N.Y.) on Wednesday urged the Biden administration to invoke the Defense Production Act to boost production and distribution of monkeypox vaccines.

“Right now there are enough vaccines in the United States to cover one-third of the community generally currently most at risk,” she said.