Monkeypox patients in Peru. WHO is concerned about a breakthrough infection in monkeypox.Photo credit: ERNESTO BENAVIDES/AFP via Getty Images
World Health Organization officials said Wednesday that there had been a “breakthrough” case of monkeypox infection and confirmed that a monkeypox vaccine was not the “magic bullet” many had hoped.
Dr Rosamond Lewis, WHO’s technical director of monkeypox, told a news conference that the breakthrough cases “give us important information that vaccines are not 100% effective in all circumstances.”
A breakthrough infection is someone who has been exposed to a high-risk person after being vaccinated, or is vaccinated to prevent infection after being exposed to a high-risk person, Lewis said.
The vaccine most commonly used to prevent monkeypox is the smallpox vaccine Jynneos, Lewis said. While data on the vaccine is sparse, limited data from studies in the 1980s suggested that the smallpox vaccine was only about 85 percent protective against monkeypox. There is currently no vaccine specifically for monkeypox.
“We’ve been clear from the beginning that a vaccine is not a panacea and all expectations of it will be dashed,” Lewis said.
She added that if people feel at high risk and want to reduce their risk, they can reduce the number of sexual partners and avoid group and/or casual sex.
More than 35,000 monkeypox cases have been reported globally since January, WHO officials said on Wednesday. There have been 12 deaths. More than 13,500 cases have been reported in the United States, according to the CDC.
Nearly 7,500 monkeypox cases were reported globally last week, a 20 percent increase from the previous week, which also saw a 20 percent increase in the number of reported cases from the previous week, WHO officials said. Almost all cases reported in Europe and the Americas have been among men who have sex with men.
Earlier this month, the U.S. Food and Drug Administration announced it would allow health care providers to administer small doses of normal doses of the Jynneos vaccine to patients in an effort to ease pressure on the vaccine‘s shortage.
Experts said that at present, the vaccine is administered by intradermal injection instead of subcutaneous injection, which can improve the effect of the vaccine and make it acceptable to give it at a reduced dose.
In an Aug. 9 press release, FDA Commissioner Dr. Robert Califf said: “The monkeypox virus has continued to spread in recent weeks, and it is clear that our current vaccine supply cannot meet current needs. Increasing the available doses could Give people who want to be vaccinated against monkeypox the opportunity to get vaccinated.”
The non-traditional method of administration was authorized because pathogens currently circulating around the world “have a significant potential to affect national security, or the health and safety of U.S. citizens living overseas,” the release said.
It wasn’t certain at the time whether the reduced-dose, interdermal vaccine would increase the risk of breakthrough cases, but experts say it may be more effective to give the vaccine in this way than the traditional full-dose. (Fortune Chinese Network)
Translated by: Liu Jinlong
Reviewer: Wang Hao