The World Health Organization (WHO) has declared mpox, previously known as monkeypox, a global public health emergency for the second time in two years due to an outbreak in the Democratic Republic of Congo that is spreading to neighboring African countries. This designation, known as a “public health emergency of international concern” (PHEIC), is the highest alert level by the WHO, facilitating accelerated research, funding, and international public health measures to contain the disease.
Earlier this week, Africa’s leading public health organization also declared mpox an emergency, citing rapid transmission of the disease. This year, over 17,000 suspected cases and 517 deaths have been reported across Africa, marking a 160% increase compared to the same timeframe last year, according to the Africa Centers for Disease Control and Prevention. Cases have been documented in 13 countries.
Mpox has two main viral clades, I and II, both of which can be transmitted through close contact with infected individuals or through contact with infected animals or contaminated materials. The current outbreak in Congo involves clade I, a strain endemic in central Africa that is known to be more transmissible and can cause more severe infections, with previous outbreaks having a mortality rate as high as 10%.
A new sub-strain of clade I, termed clade Ib, is now emerging and appears to spread more easily during routine close contact, including sexual interactions. This has raised alarms as the strain has spread from Congo to neighboring nations like Burundi, Kenya, Rwanda, and Uganda, prompting the WHO’s response.
WHO Director-General Tedros Adhanom Ghebreyesus emphasized the necessity of an international coordinated response to effectively manage these outbreaks and safeguard lives.
In contrast, clade II, which was responsible for the worldwide spread of mpox in 2022, has milder infections, with more than 99.9% of cases resulting in survival, according to the U.S. Centers for Disease Control and Prevention (CDC). This strain primarily spread through sexual contact among men who have sex with men and was classified as clade IIb. The WHO lifted its emergency declaration for this clade ten months later, as cases in the U.S. significantly decreased.
Despite the drop in U.S. cases, the CDC has alerted healthcare providers to be vigilant for mpox symptoms in individuals who have recently been in the DRC and surrounding regions. Currently, no cases of clade I have been reported outside of central and eastern Africa, but the CDC cautions about the potential for further transmission.
The CDC has issued travel advisories for those going to the DRC and nearby countries, recommending enhanced safety measures and immediate medical consultation if symptoms arise. The U.S. Department of Health and Human Services stated that the country is prepared to identify and manage any potential cases of clade I, monitoring the virus through clinical testing and wastewater surveillance.
Should a clade I case arise in the U.S., health officials expect it to result in lower morbidity and mortality rates than in the DRC.
Mpox typically manifests with a rash that resembles chickenpox, syphilis, or herpes, progressing into small bumps, blisters filled with fluid, and is often accompanied by fever, headaches, muscle aches, back pain, fatigue, and swollen lymph nodes.
A vaccine for mpox is available in the U.S., although it is not widely accessible in the DRC. To bridge this gap, the U.S. is donating 50,000 vaccine doses. The CDC recommends that individuals at higher risk of infection, including those recently exposed to the virus and men who have sex with men, receive two doses of the vaccine, which is effective against both clades of mpox.