Centers for Disease Control and Prevention (CDC) Director Rochelle Walensky, MD, MPH, said today that the monkeypox outbreak in the United States will likely get worse in the coming weeks as thousands of more tests are made available to clinicians across the country.

In an hour-long press conference, Walensky was joined by members from the Department of Health and Human Services (HHS) to address testing, transmission, and vaccination against the virus.

"We have the capacity for testing," Walensky said. "Now we must look to clinicians and colleagues to make sure proper screening and counseling are taking place."

Of 700 cases in the United States with available demographic information, Walensky said almost all were among men who have sex with men (MSM). She cautioned that this group—which will be among the first to be offered Jynneos, a monkeypox vaccine—must understand they are not fully protected from the virus until 2 weeks after their second dose of the vaccine.

"One dose is not enough," said Walensky. She also urged MSM to minimize anonymous sex and sex with multiple partners as the outbreak is ongoing.