In keeping with the CDC, a single dose of monkeypox vaccine gives some safety towards an infection

Los Angeles, CA – August 10: Luis Garcia, a registered nurse, prepares a monkeypox virus vaccine at St.John’s Well Child & Family Center on Wednesday, August 10, 2022 in Los Angeles, CA.

Irfan Khan | Los Angeles Times | Getty Images

People at risk for monkeypox who have not received a single dose of the vaccine are 14 times more likely to become infected than those who have received a vaccine, according to the Centers for Disease Control and Prevention.

The preliminary data, collected from late July to early September across 32 states, is the first concrete evidence that the Jynneos vaccine provides at least some protection against infection with the monkeypox virus circulating in the current outbreak.

“These new data give us cautious optimism that the vaccine is working as intended,” said CDC Director Dr. Rochelle Walensky to reporters during an update on Wednesday.

The data suggest that even a single dose of the vaccine provides protection against infection as early as two weeks after vaccination, Walensky said. Produced by the Danish company Bavarian Nordic, the vaccine Jynneos is given in two doses 28 days apart.

Walensky said while data on a single dose is promising, laboratory studies have shown that immune protection is highest two weeks after the second dose.

“For this reason, despite this promising data, we continue to strongly recommend that people receive two doses of the Jynneos vaccine 28 days apart to ensure durable and long-lasting immune protection against monkeypox,” Walensky said.

Monkeypox is spread primarily through close skin-to-skin contact during sex among gay and bisexual men. The virus is rarely fatal, but it causes a blister-like rash that can be very painful and, in some cases, lead to hospitalization.

The CDC director said vaccinated individuals should continue to protect themselves from infection by avoiding close contact with individuals with monkeypox and reducing behaviors that put a higher risk of exposure to monkeypox.

When asked when vaccinated people can resume normal sexual behavior, Walensky said the CDC is waiting for real-world data on the effectiveness of the second dose of the vaccine.

“What we have at the moment is data on how well and how our vaccine works after a single dose. What we don’t yet have is what happens after a second dose and how durable that protection is,” Walensky said.

This is the first time the US has used jynneos to control a large outbreak of monkeypox. As a result, there is little data on the actual effectiveness of the vaccine. The Food and Drug Administration first approved the Jynneos vaccine in 2019 based on human immune response data.

Extended Permission

The CDC is also justifiably expanding to make sure people get the vaccine before they’re exposed to monkeypox, and not after known or suspected exposure to the virus.

This includes gay, bisexual and transgender men who have had more than one sexual partner in the past six months, had sex in a location associated with a higher risk of monkeypox, or had a sexually transmitted infection during this period. Sexual partners of people at these risks can now also be vaccinated, including sex workers.

Demetre Daskalakis, deputy chief of the White House monkeypox task force, said the federal government is also urging vaccine providers to make it easier for people to get vaccinated and reduce fears of stigma.

“Fear of disclosure of sexuality and gender identity must not be a barrier to vaccination,” Daskalakis said.

New CDC guidelines also allow people to receive the vaccine in the shoulder or upper back, so clothing will cover the temporary mark left by the shot. Some people don’t want to get shot in their forearm because they feel the mark is stigmatizing, Daskalakis said.

The US is battling the world’s largest monkeypox outbreak, with more than 25,000 reported cases in every US state plus Washington, DC and Puerto Rico, according to CDC data. There has been one confirmed death from the virus in the United States since the outbreak began in May.

Monkeypox cases have been falling across the country in recent weeks after the virus swept the United States in the summer.

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