Background

The mpox virus, which is in the same family as smallpox, is endemic to Central and Western Africa. The virus is primarily spread through close contact with infected animals, people, or the consumption of contaminated meat.

Some of the symptoms of mpox include fever, headache, muscle aches, and a rash that can progress to pustules. Symptoms can last between two to four weeks, with treatment relying heavily on supportive care and reducing symptoms.

In July 2022, WHO declared mpox a global health emergency after cases spread to 87 countries, including 80 countries that historically hadn't seen the disease before. In August, the United States followed suit by declaring its own public health emergency for the disease. During the 2022 outbreak, nearly all monkeypox cases in the United States were the result of male-to-male sexual contact.

Vaccination helped to reduce the spread of the disease in United States. In 2022, there were over 30,000 U.S. mpox cases, which declined to around 1,700 in 2023.

WHO declares mpox a global health emergency

Last week, WHO declared mpox a global health emergency for the second time in three years. In the current outbreak, the disease has spread rapidly through several African countries, with the Democratic Republic of Congo seeing the most cases. So far, only one other country outside of Africa, Sweden, has confirmed a new mpox case linked to the current outbreak.

Since the beginning of the year, Congo has reported 15,600 mpox cases and 537 deaths. The people most at risk are women and children under the age of 15.

Several countries have reported different strains of mpox, including clade IIb and clade Ib. Clade IIb was responsible for the 2022 international outbreak, while clade Ib, which evolved through person-to-person contact, is responsible for the current outbreak.

"The detection and rapid spread of a new clade of mpox in eastern DRC, its detection in neighboring countries that had not previously reported mpox, and the potential for further spread within Africa and beyond is very worrying," said WHO Director-General Tedros Adhanom Ghebreyesus. "In addition to other outbreaks of other clades of mpox in other parts of Africa, it's clear that a coordinated international response is essential to stop this outbreak and save lives."

According to Dimie Ogoina, a Nigerian infectious disease expert and chair of WHO's new mpox emergency committee, said understanding how the virus spread through different populations and countries will be critical to combatting future mpox outbreaks. Before countries can vaccinate patients effectively, they need to understand how the virus is being transmitted in their populations.

"It's very important for you to understand your outbreak for you to ultimately decide what groups of persons to vaccinate. And we have that gap in parts of Africa where we don’t fully understand the transmission dynamics and the risk factors for mpox," Ogoina said.

So far, Congo has approved two mpox vaccines, Bavarian Nordic's Jynneos and a Japanese product called LC16. However, the country does not have an immunization plan in place yet, and few vaccines are available. Currently, Bavarian Nordic has donated 15,000 doses of Jynneos and the United States pledged to donate 50,000 vaccines, but these won't be enough to control the outbreak.

"The challenge is that these vaccines are not sufficient," even if countries try to vaccinate only those at the highest risk, Ogoina said.

According to Anne Rimoin, an mpox expert from the University of California, Los Angeles, getting the current outbreak under control will be a difficult task, since the conditions that lead to spillovers from animals to humans are poorly understood. A lack of surveillance in the populations where the cases are occurring will also affect the response.

"We're just picking up pieces of what's actually happening because surveillance is not robust," Rimoin said. "We're dealing with vulnerable and hard-to-reach populations … whether you're talking about [infected people in] remote rural areas or men who have sex with men or sex workers." (Mandavilli, New York Times, 8/14; Sampson, New York Times, 8/14; Goldman, Axios, 8/14; Cheng, Associated Press, 8/14; Branswell, STAT, 8/14; Fortinsky, The Hill, 8/15)

Writing for the Harvard Business Review, Jeff Levin-Scherz, Patricia Toro, Siupo Becker, and Meg Alexander of  WTW detail six considerations for employers to create effective policies that help protect workers from monkeypox.