May 19, 2022 - Science

What we know about the new monkeypox outbreak

Confirmed new monkeypox cases outside of Africa
Note: Monkeypox is more common and locally transmitted in west and central Africa; Data: WHO, Axios reporting; Map: Axios Visuals

A monkeypox outbreak in several European countries and one U.S. state may become the largest outbreak of the virus outside of Africa, but it's not likely to cause a global pandemic like COVID, an infectious disease expert tells Axios.

Why it matters: The CDC has confirmed at least nine cases in the United States. The current outbreak is small so far and scientists continue gathering data, but there may be community transmission of the virus.

  • "I'm sure that ultimately this will be the largest outbreak of monkeypox that we've had outside of the endemic areas in Africa," says Daniel Bausch, infectious disease expert and president of the American Society of Tropical Medicine & Hygiene.
  • "I don't think there's a reason for panic. I don't think we're going to have tens of thousands of cases," he tells Axios.

What's happening: Various countries are reporting confirmed and possible cases, including Australia, Canada, Belgium, Italy, the United Kingdom, Portugal, Sweden, Spain, Netherlands, Germany and France, per the World Health Organization.

  • Argentina on Friday reported its first case of monkepox and announced another suspected case of the disease, according to Reuters.
  • Related to smallpox, monkeypox has two main types: the West African clade with a fatality rate of around 1% and the Congo Basin (Central African) clade, with a fatality rate of around 10%.
  • The current circulating strain appears to be the milder West African type that often starts with flu-like symptoms and swelling lymph node, progressing to a blistering rash.
  • The smallpox vaccine is believed to be effective against monkeypox.

Details: Monkeypox, which can be transmitted by droplets and by close contact with infected skin lesions or contaminated materials, usually incubates in people for 6 to 13 days before symptoms appear.

  • Transmission can come from animals or human-to-human but "it is generally documented among very close contacts. So family members, people taking care of ill patients. Or health care providers," Andrea McCollum, the poxvirus epidemiology team lead at the CDC, told STAT News.
  • Children are at higher risk, and monkeypox can cause pregnancy complications or stillbirth, per the WHO.

In the U.S., there have been reports of individuals infected with monkeypox before, particularly in international travelers from Nigeria, including a case in Texas and one in Maryland last year.

  • Per the CDC, monkeypox re-emerged in Nigeria in 2017 after more than 40 years with no reported cases.

Between the lines: The improvement in the global infectious diseases surveillance system is paying off with not only COVID but disease like monkeypox, Bausch adds.

What's next: WHO is scheduled to meet next week to discuss pox viruses, per STAT.

Go deeper: First U.S. monkeypox case confirmed in Massachusetts

Editor's note: This post was updated to include countries that announced new confirmed cases of monkeypox.

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