Massachusetts to prioritize first-dose monkeypox vaccine

The new strategy is in response to a limited supply of Jynneos and aims to provide the broadest possible protection to the public.

Starting Monday, Massachusetts healthcare providers will prioritize the first dose of the monkeypox vaccine due to a severely limited national supply. 

The new strategy aims to cover as many eligible patients as possible amid a shortage of doses. Although the vaccine, Jynneos, is approved as a two-dose series, the state’s Department of Public Health (DPH) recommends providers limit the dose to one until further notice to ensure the maximum number of people have protection.

Dr. Paul Biddinger, chief preparedness and continuity officer at Mass General Brigham, says the new strategy will double the number of Massachusetts patients that can be treated with the vaccine.


“The good news is there really is good, existing data that says a single-dose strategy provides highly-effective protection and durable ongoing protection,” Dr. Biddinger told

As of Thursday, there were 42 new Massachusetts cases of monkeypox since the week prior, bringing the total to 157 residents. The first case was reported on May 18. Health officials say the new cases were all in adult males.

“What we’re seeing, unfortunately, is a continued increase in the number of monkeypox cases in the commonwealth, as well as across the country,” said Biddinger. “We know that the number of available vaccine doses is limited. But the vaccine is highly effective in protecting people at high-risk and post-exposure prophylaxis. Those people that get a first dose are really well-protected.” 

DPH officials sent a message to vaccine providers Friday alerting them of the shift in focus, NBC Boston reported.

According to an update on the state’s website, people who have already scheduled second dose appointments will receive them, but no new second-dose appointments will be scheduled until more doses become available.

Fourteen healthcare providers and locations across the state currently offer monkeypox vaccines. As of Thursday, 5,875 doses of Jynneos were administered in Massachusetts.


Other states that have adopted a first-dose prioritization strategy include Rhode Island, Connecticut, California, Michigan, and Washington, D.C. Chicago and Philadelphia have taken similar measures.


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