The Centers for Disease Control and Prevention (CDC) said Monday that health authorities in the U.S. are releasing some Jynneos vaccine doses for the treatment of the monkeypox virus.
More than 1,000 doses of the two-dose vaccine are in the Strategic National Stockpile, according to Capt. Jennifer McQuiston, the deputy director of the CDC's High Consequence Pathogens and Pathology division.
"We expect that level to ramp up very quickly in the coming weeks as the company provides more doses to [the U.S.]," McQuiston said at a media telebriefing. Jynneos, made by Bavarian Nordic A/S, has been approved in the U.S. since 2019 for use against smallpox and monkeypox in high-risk adults aged 18 and older.
She said there are two vaccines that could be used to prevent monkeypox and they are available in different levels.
"We have a good stock of vaccine. We've been preparing for the possibility of needing to use it for smallpox," she told reporters.
Alternatively, there are about 100 million doses of the older smallpox vaccine, ACAM2000.
McQuiston said ACAM2000 potentially has significant side effects and there would have to be some "serious discussion" before it is widely used.
Unlike ACAM2000, Jynneos is an attenuated live virus vaccine and no severe adverse events were identified when studied in people with HIV and topic dermatitis.
While there has been one confirmed monkeypox virus case in the U.S. since the recent outbreaks, there are also four confirmed cases of Orthopoxvirus.
Monkeypox belongs to the Orthopoxvirus family of viruses, the agency notes.
President Biden said over the weekend that recent cases of monkeypox that have been identified in Europe and the United States were something "to be concerned about."
Reuters and The Associated Press contributed to this report.