Mpox: A Growing Public Health Concern
The World Health Organization has declared mpox a public health emergency of international concern, with over 15,600 cases and over 530 deaths reported in the Democratic Republic of the Congo and neighboring countries in Africa. As a researcher with over three decades of experience in public health and medical laboratories, I’ll delve into the current outbreak and what history tells us about mpox.
A Cousin of Smallpox
Mpox is caused by the monkeypox virus, a member of the Poxviridae family, which includes smallpox, vaccinia, and cowpox viruses. While an animal reservoir for the virus is unknown, African rodents are suspected to play a part in transmission. The virus has only been isolated twice from an animal in nature, and diagnostic testing is currently only available at Laboratory Response Network labs in the U.S. and globally.
Epidemiology
Since the first reported human case in 1970, mpox has been found in several central and western African countries, with the majority of infections in the DRC. Cases outside of Africa have been linked to international travel or imported animals, including in the U.S. and elsewhere. The first reported cases in the U.S. were in 2003, linked to a shipment of animals from Ghana, and there have been ongoing outbreaks since May 2022.
Transmission
The virus can be transmitted through contact with an infected person or animal, or contaminated surfaces. It typically enters the body through broken skin, inhalation, or mucous membranes in the eyes, nose, or mouth. Researchers believe that human-to-human transmission is mostly through inhalation of large respiratory droplets rather than direct contact with bodily fluids or indirect contact through clothes.
Signs and Symptoms
After infection, symptoms usually don’t appear until one to two weeks later. Mpox produces smallpox-like skin lesions, but symptoms are usually milder than those of smallpox. Flu-like symptoms are common initially, ranging from fever and headache to shortness of breath. A rash can appear on the extremities, head, or torso, eventually turning into blisters filled with pus. Symptoms usually last two to four weeks, while skin lesions usually scab over in 14 to 21 days.
Vaccines and Treatments
Treatment for mpox is primarily focused on relieving symptoms, as there are no available treatments to cure the infection. The smallpox vaccine can provide protection against infection from both viruses, and one vaccine, Imvamune or Imvanex, is licensed in the U.S. to prevent mpox and smallpox. Vaccination after exposure to the virus may also help decrease the chances of severe illness. The CDC currently recommends smallpox vaccination only in people who have been or are likely to be exposed to mpox, with immunocompromised individuals at high risk.
As the world grapples with this growing public health concern, it’s essential to understand the history and epidemiology of mpox to effectively combat its spread.
