Get the mpox vaccine. Although mpox frequency has declined dramatically since its peak last summer, there is reason to worry it will come roaring back among men who have sex with men. Summer (warm weather) might have an impact on transmission risk and development of mpox lesions which, as you likely know, dominate in warm/sweaty body areas. That's a speculative but not unreasonable interpretation of its summertime peak last year. Therefore, all MSM should be vaccinated. It's a very well tolerated vaccine, with low chance of side effects, regardless of your past history of vaccine problems -- unless, of course, you had a severe reaction of some sort like anaphylaxis or other serious allergic problem, Guillain-Barré syndrome, and the lie. (An exception might be warranted in some settings, e.g. if the vaccine is in short supply or if mpox hasn't been frequent in a particular community or geographic area. You could check with your local health department or a sexual health clinic.)

Past smallpox vaccine likely reduces risk and/or severity of mpox, but not by much. It makes no difference in vaccination recommendations.

Note the terminology I have used. Mpox, not monkeypox, is now preferred and recommended.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

I have discussed this with some colleagues with more direct experience and advice. The mpox vaccine (JYNNEOS) was devloped to prevent smallpox and works well against mpox. Research is underway to learn whether the older smallpox vaccines, used most frequently (in the US) in military personnel, provide protection and, if so, how long protection lasts. Preliminary results of one study, not yet published but presented at a scientific conference found that being vaccinated an average of 13 years previously reduced the risk of mpox and for hospitalization for it by 60-70%. Pretty good but definitely not complete protection. More studies are needed, but these early results support the consensus advice that MSM should receive the current JYNNEOS smallpox vaccine being offered for mpox prevention in most (nearly all?) public health sexual health clinics and elsewhere. It is likely, but not yet proved, that JYNNEOS acts like a booster -- i.e. protection against mpox might be maximal in those, like you, who receive it in addition to past smallpox immunization. You may be especially safe after getting it.