WASHINGTON (AP) — U.S. health officials on Tuesday approved a plan to maximize the limited supply of monkeypox vaccine by giving one-fifth the usual dose, citing research that shows a small amount has almost the same efficiency.
This dose-saving strategy also envisages that the Jynneos vaccine be injected only subcutaneously and not more deeply, a practice that can improve the response of the immune system. Patients will still receive two doses four weeks apart.
This highly unusual move is a stark admission that the United States lacks the supply needed to inoculate everyone who wants to protect themselves from the virus.
Authorities estimate that between 1.6 million and 1.7 million Americans face the greatest risk from the disease, primarily men with HIV or men who are at higher risk of contracting it. To vaccinate this group, more than 3.2 million doses are needed.
White House officials said that under the new policy, the 440,000 regular doses available would multiply to more than 2 million reduced doses.
“It’s safe, it’s effective, and it will significantly increase the volume of vaccine doses available to communities across the country,” Robert Fenton, White House coordinator for monkeypox response, told reporters.
Last week, the Biden administration declared monkeypox a public health emergency in an effort to contain an outbreak that has infected more than 8,900 Americans.
The Food and Drug Administration (FDA) has approved the new strategy for adults 18 years of age and older who are at high risk for monkeypox infection. Younger people will also be able to get the vaccine if they are considered to be at high risk, although they will need to get the shot at the regular dose, the agency said.
FDA officials stressed that the second dose is crucial to ensure protection.
“We strongly believe in the need for two doses, partly because we have no evidence that people are adequately protected with a single dose 3, 6 or 8 months later,” said Dr. Peter Marks, chief vaccines officer. from the FDA.
Regulators pointed to a 2015 study showing that inoculation with a fifth of the traditional two-dose vaccine generated a robust immune system response comparable to the full dose. About 94% of people who received the smaller dose had adequate levels of antibodies against the virus, compared to 98% of those who received the full dose, according to the NIH-funded study. acronym in English).
The NIH is planning a further trial of the technique. And Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention, said her agency is already beginning to track real-world vaccine effectiveness in American communities, though initial estimates will take time. in being generated.
But some experts worry that, with little data to support the policy, it could backfire if it reduces the effectiveness of vaccines.
“We are very concerned about the scant amount of research that has been done on this dose and method of administration, and fear that it will give people a false sense of confidence that they are protected,” said David Harvey of the National Coalition of Directors of Health. STD, in a statement.
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