Monkeypox Vaccine Efficacy Disclosed

The most robust clinical evidence for the effectiveness of the monkeypox virus (MPX) vaccine was published today by the U.K. Health Security Agency (UKHSA).

The UKHSA estimates that the two-dose JYNNEOS® (MVA-BN, IMVAMUNE®) vaccine effectiveness for a single dose was 78% fourteen or more days after the initial vaccination.

Out of 363 MPX patients in this analysis between July and November 2022, eight had been vaccinated at least 14 days, and 32 had been vaccinated between 0 to 13 days.

More than 55,000 doses of the monkeypox vaccine have been delivered in the U.K. since the MPX outbreak began in May 2022.

As of November 21, 2022, there were 3,720 total MPX cases.

Of these, 96 were in Scotland, 34 were in Northern Ireland, 47 were in Wales, and 3,543 (69%) were in England.

About 98% were men, and 52 were women, with a median age of 37. 

This limited analysis offers hope that people can be protected as this outbreak wanes. However, this UKHSA analysis was not a randomized, peer-reviewed clinical trial.

Jamie Lopez-Bernal, Consultant Epidemiologist at UKHSA, said in a press release on November 22, 2022, "While monkeypox cases are low, it remains vital to stay alert to the risks."

"We now know that a single vaccine dose provides strong protection against monkeypox, which shows just how important vaccination is to protect yourself and others."

"A second dose is expected to offer even greater and longer-lasting protection."

"Please come forward for your vaccine as soon as possible – don't put it off."

"Remember that it takes two weeks for the vaccine to maximize the effect, so the sooner you get vaccinated, the better."

The UKHSA confirmed it would continue investigating the duration of protection from a single vaccine dose and the combined protection of two doses.

 In the U.S., 1,090,222 first and second doses of Jynneos were administered in the 57 U.S. Jurisdictions reporting data as of November 15, 2022.

The U.S. CDC recommends anyone exposed to MPV and people who may be more likely to contract the virus should be vaccinated. 

Additional monkeypox vaccine news is posted at PrecisionVaccinations.com/Monkeypox.

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