The World Health Organization (WHO) recently announced a name change for a viral infection that’s been around for decades: monkeypox should now be called mpox. The shift came after large-scale global outbreaks sparked deliberation over whether the term monkeypox could be stigmatizing.

Even though the monkeypox virus was first isolated from a colony of cynomolgus monkeys in the 1950’s, the term is a misnomer. Monkeys can be intermediate hosts to the virus, yes, but they are not the natural reservoir and do not seem to play a role in the virus lifecycle or as a common vector for transmission to humans.

The first human case of monkeypox virus infection was reported in 1970 in a nine-month-old child living in the Democratic Republic of Congo. Until 2022, monkeypox was almost exclusively confined to the African continent, with sporadic cases and small outbreaks usually occurring in Central and West Africa.

One notable outbreak outside of Africa occurred in the United States in 2003, which was linked to the importation of Gambian pouched rats from Ghana. The rodents transmitted monkeypox virus to prairie dogs in the same animal facility. The prairie dogs were subsequently sold in the U.S. as pets. Seventy-nine human cases of monkeypox infection were officially recorded, and no human-to-human transmission occurred.

The largest monkeypox virus outbreak ever recorded — more than 83 thousand cases occurring in more than 100 countries — started in May 2022. This outbreak differed epidemiologically and clinically from those originating in Africa. With so many cases affecting the Western world, concerns were raised over racist and stigmatizing potential of monkeypox, prompting the WHO decision.

However, the new nomenclature is not without its challenges. The biggest issue in renaming monkeypox to mpox is that the International Committee on the Taxonomy of Viruses (ICTV) did not simultaneously change the name of the infectious virus. That is, the virus that causes mpox is still called monkeypox virus.

It is not unusual for infectious disease names to vary from their causative pathogens. Some examples include:

  • COVID-19 is caused by SARS-CoV-2 infection
  • AIDS is caused by untreated HIV infection
  • Plague is caused by Yersinia pestis infection

Similarly, mpox (the disease) is caused by monkeypox virus infection.

Going forward, the clinical manifestations of monkeypox virus infection (including its characteristic rash) should be referred to as mpox. For example, instead of stating “monkeypox rash” one should now use “mpox rash”. Similarly, “tecovirimat is a treatment option for mpox” instead of “tecorvirimat is a treatment option for monkeypox”.

However, given that it will be just as valid to state “patient with mpox” as it will be to say “patient with monkeypox virus infection” it’s hard to imagine the term monkeypox phasing out completely, unless the ICTV renames the virus as well.