Mpox, formerly known as monkeypox, is a rare disease caused by infection with the Monkeypox virus (MPXV). It's related to smallpox, but symptoms are typically milder and mpox is rarely fatal.
Mpox was discovered in Denmark in 1958 when two outbreaks of a pox-like disease occured in research monkeys. The first reported human case of mpox was recorded in 1970. In spite of being called “monkeypox,” the natural source of mpox remains unknown. However, animals thought to harbor the virus and possibly infect humans include rodents, pigs, prairie dogs, hedgehogs, and non-human primates such as monkeys found in the African regions where mpox was previously widely reported.
Mpox is endemic (regularly occuring) in certain parts of West and Central Africa. But since early May of 2022, cases of this disease have been reported from countries where it is typically does not occur, such as Europe and North America. Between January 2022 and August 2024 mpox has been reported in more than 120 countries with over 100 000 laboratory-confirmed cases reported and over 220 deaths among confirmed cases.
Mpox can spread from person to person or occasionally from animals to people. It can also be spread by contact with contaminated objects.
Person-to-person transmission of mpox can occur through close, often skin-to-skin, or intimate contact. This can include direct contact with the rash or other lesions of a person infected with mpox, in addition to contact with the infected persons saliva, areas around the anus, rectum, or vagina, and respiratory tract secretions such as mucus and snot.
Pregnant people infected with mpox can transmit the virus to the fetus in utero and by close contact during and after birth.
Transmission can occur through contaminated objects such fabrics, and surfaces that have not been disinfected after use by someone with mpox.
Animal to human transmission of mpox can occur from an infected animal to a human through bites or scratches, or during activities like hunting, skinning, trapping, cooking, or eating animals. Infected humans can spread mpox to animals through close contact, such as petting, hugging, kissing, and sharing sleeping areas or food.
New data shows that some infected people can spread mpox to others from 1-4 days before symptoms appear until the rash has completely healed and a new layer of skin has formed.
The primary symptom of mpox is a rash which may be located on the hands, feet, face, chest, mouth or near the genitals, including the vagina, labia, testicles, and penis, or around the anus.
The Mpox rash progresses through several stages. First, it may appear like a pimple or blister and feel itchy and painful. As the rash heals, the lesions dry up, scab over and fall off.
Other symptoms of monkeypox may include fever, chills, muscule aches, back pain, low energy levels, swollen lymph nodes, headache, sore throat, and respiratory symptoms. Some people may also experience flu-like symptoms before the rash appears.
Mpox symptoms typically begin within a week, but can appear up to three weeks after viral exposure. If flu symptoms develop, the rash usually appears one to four days later. Some individuals may experience just a few symptoms while others may experience all of them.
In most cases, mpox generally lasts for 2-4 weeks; however, it can last longer or have severe or fatal health complications in some vulnerable populations, such as immunocompromised individuals.
Complications due to mpox include pneumonia, secondary skin infections, blood infection, eye issues like corneal infection with loss of vision, pain or difficulty swallowing, dehydration, and swelling of the brain, heart, rectum, genital organs, or urinary passages.
The best way to prevent mpox is to keep up to date with recommended vaccines.
Additional ways to reduce the risk of contracting the virus, include:
There is one vaccine licensed for use in the United States. It protects against both mpox and smallpox:
JYNNEOS®(Smallpox and Monkeypox Vaccine, Live, Non-replicating)
JYNNEOS® is a 2-dose vaccine series recommended for adults 18 years of age and older determined to be at high risk for mpox or smallpox disease. Doses should be separated by 4 weeks (28 days).
The Centers for Disease Control and Prevention (CDC) recommends vaccination against mpox in those who:
References
Centers for Disease Control and Prevention. Mpox Vaccination. https://www.cdc.gov/mpox/vaccines/index.html. January 10, 2025. Accessed January 17, 2025.
Centers for Disease Control and Prevention. How Mpox Spreads. https://www.cdc.gov/mpox/causes/index.html#cdc_causes_how_it_spreads-how-it-spreads. December 11, 2024. Accessed January 17, 2025.
Centers for Disease Control and Prevention. Signs and Symptoms of Mpox. https://www.cdc.gov/mpox/signs-symptoms/index.html. September 12, 2024. Accessed January 17, 2025.
WHO. Mpox. https://www.who.int/news-room/fact-sheets/detail/mpox. August 26, 2024. Accessed January 17, 2024.
Bavarian Nordic. Jynneos. https://jynneos.com/. Accessed January 17, 2024.
These articles are not a substitute for medical advice, and are not intended to treat or cure any disease. Advances in medicine may cause this information to become outdated, invalid, or subject to debate. Professional opinions and interpretations of scientific literature may vary. Consult your healthcare professional before making changes to your diet, exercise, or medication regime.