Whether or not monkeypox (MPX) should be labeled a sexually transmitted infection (STI) isn't much of a debate among STI experts.

So far, more than 95% of cases in the United States have been acquired during sexual contact among men who have sex with men (MSM). To not call it an STI is nearly equivalent to saying syphilis isn't an STI because exceptions to sexual transmission are common in some settings.

Pragmatically, MSM should be advised that certain sexual practices and lifestyles put them at very high risk of MPX. As well as its opposite: That modified sexual exposures can be nearly 100% protective.

Just yesterday, the Centers for Disease Control and Prevention (CDC) published a report documenting an intimate association between MPX and other STIs in MSM in the United States. The CDC has long advised screening patients who have newly diagnosed STIs for other STIs, and it recommends STI screening all persons evaluated for MPX, implicitly recognizing MPX as an STI.

Recently reported cases of MPX in persons other than MSM is similar to the course of HIV transmission in the early years of HIV/AIDS in industrialized countries. But the dominant sexual transmission of HIV among MSM, and its characterization as an STI in them, remains valid.