Canada's National Advisory Committee on Immunization (NACI) is strongly recommending "dose sparing strategies" to offer more people the monkeypox vaccine, including second doses.
Imvamune, the only monkeypox vaccine available in Canada, normally should be given subcutaneously in two doses, 28 days apart. However, because of limited supplies, provinces have offered first doses only to people at higher risk of infection, including sex workers and men who have sex with men.
In updated guidance, NACI strongly recommends that second doses should be offered "when supply is not constrained."
So long as supplies are limited, however, provinces should consider "dose sparing strategies," including prioritizing first doses, even when that means some people may wait longer than 28 days for a second shot, as well as giving one-fifth of the normal second dose intradermally to stretch supplies further.
Although evidence supporting these strategies is limited, NACI says federal...