Mpox (Monkeypox)

Mpox (monkeypox) is a rare disease caused by infection with the mpox virus. Mpox was first identified in 1958 when two outbreaks of pox-like disease occurred in colonies of research monkeys. The source of mpox is unknown.

What is Mpox (Monkeypox)?

Mpox is a disease caused by the mpox virus, which belongs to the Orthopoxvirus genus. This genus also includes variola virus, which causes smallpox, and vaccinia virus (used in the smallpox vaccine), and cowpox virus. However, mpox is not related to chickenpox.

Mpox is a zoonosis, which is a disease that is transmitted from animals to humans. Mpox occurs in rodents and non-human primates and is generally found in central and West Africa. The first human case of mpox was observed in 1970.

Outbreaks

The last mpox outbreak in the United States occurred in 2003. Forty-seven people located primarily in the Midwest were infected through contact with domestic prairie dogs. The prairie dogs were exposed to an infected Gambian pouched rat imported from Ghana while living in a shared space in a pet store.

Until 2022, most cases of mpox that occurred outside of Africa were related to people traveling internationally or the import of animals from places where the disease is more common. In 2022, multiple mpox cases were reported in several countries worldwide where mpox is typically not present, including in the United States. The 2022 outbreak is significant because an unusually high number of cases have occurred through human-to-human transmission, rather than animal-to-human transmission.

Learn more about the U.S. outbreak

Symptoms

Mpox has symptoms that are similar to smallpox, a related virus; however, mpox symptoms are milder and the disease is rarely fatal. The incubation period for mpox ranges from 5 to 21 days (three weeks), although symptoms are most likely to occur within 7 – 14 days after infection. Symptoms can include the following:

• Fever
• Headache
• Muscle aches and backache
• Swollen lymph nodes
• Chills
• Exhaustion
• A pimple- or blister-like rash on the face, inside the mouth and other parts of the body like the hands, feet, chest, genitals or anus

Mpox can be spread from the time symptoms start until the rash has healed—meaning all scabs have fallen off and a fresh layer of skin has formed.

• People infected with mpox may get all or only some of the symptoms
• People who develop flu-like symptoms will usually develop a rash one to four days later
• Some people get the rash before other symptoms follow; others only have the rash
• The rash goes through different phases before healing; after forming, the rash turns into raised bumps which fill with fluid. The rash scabs over and, eventually, the scabs fall off

Most people recover in 2-4 weeks. The disease can be more serious in people who are pregnant, children or immunocompromised.

Transmission—How Mpox Spreads

Mypox can spread to anyone through close personal contact, including:

• Direct contact with an infected rash, scab or body fluids
• Respiratory droplets during prolonged, face-to-face contact or during intimate physical contact such as kissing or sex
• Touching items that have been in contact with an infected rash or body fluids, such as clothing or bed sheets
• From a pregnant person to the fetus through the placenta

Close personal contact includes:

• Oral, anal and vaginal sex or touching the genitals (penis, testicles, labia or vagina) or anus or a person with mpox
• Hugging, massage, kissing
• Prolonged face-to-face contact
• Touching fabrics and objects during sex that were used by a person with mpox such as bedding, towels, fetish gear and sex toys that have not been disinfected

Scientists are still learning about:

• Whether the virus spreads when someone has no symptoms
• How often it’s spread through respiratory secretions
• When a person with mpox symptoms might be more likely to spread the virus through respiratory secretions
• If mpox can be spread through semen, vaginal fluids, urine or feces (poop)

Learn more

Spread to and From Animals or Pets

Mpox is a zoonotic disease, which means it can be spread from animals to humans through scratches or bites or by preparing or consuming the meat of an infected animal.

Mpox can also be spread from humans to animals, although medical experts are still learning which animals can get mpox. Learn how to prevent spreading the virus to animals.

Diagnosis

Mpox is diagnosed by using a polymerase chain reaction (PCR) test to detect the virus’s DNA. Diagnostic specimens are collected from the rash, using skin, fluid, crusts or biopsy.

Treatment

There are no specific mpox infection treatments. However, because mpox and smallpox viruses are genetically similar, antiviral drugs developed for smallpox may be used to treat mpox virus infections. Patients who are more likely to get severely ill may be recommended an antiviral like tecovirimat (TPOXX), which is approved by the FDA for the treatment of smallpox.

Vaccines

Under specific circumstances, certain smallpox vaccines may be used for post-exposure prophylaxis in individuals at high risk of exposure. The United States maintains stockpiles of two vaccines, JYNNEOS and ACAM2000, that can prevent mpox in people who have been exposed to the virus. These vaccines may also be recommended for people who have had an exposure to someone who has mpox.

In 2022, multiple mpox cases were reported in several countries worldwide where mpox is typically not present, including in the United States. On May 27, 2022, DOH and Public Health Seattle-King County identified and confirmed a case of mpox virus infection in King County. For the latest information and case numbers in Washington state, please see the following resources:

• Washington State Department of Health MPV (Monkeypox)
• Centers for Disease Control and Prevention 2022 U.S. Map & Case Count (see Washington State Data)

Mpox is considered a rare disease in the United States and becoming infected through casual contact with an infected person typically does not result in transmission.

While anyone can get mpox, there are people who are at higher risk for becoming infected. Even though cases internationally and nationally have mainly involved men who have sex with men, anyone who is sexually active with multiple partners or who has sex with someone else who has multiple sex partners may be at risk for exposure to mpox.

Sex

• Talk with any current sexual partners. It can be difficult to have these conversations, but it’s important for you to be on the same page as you discuss your tolerance for risk and to check in with each other about any recent illness and being aware of any new or unexplained rashes on your body or your partner’s body. If you or your partner are experiencing symptoms of mpox or know that you have mpox, the best thing you can do to protect yourself and others is to avoid sex of any kind (oral, anal or vaginal). Do not touch or kiss while sick and do not share towels, sex toys or toothbrushes. See a healthcare provider as soon as possible.
• If you or your partner believe you have (or might have) mpox and decide to have sex anyway, there are things you can do to limit risk—see this fact sheet for more information.
• If you are experiencing symptoms of mpox or think (or know) that you have mpox, avoid gatherings, especially if they involve close, personal, skin-to-skin contact.

Social Gatherings—Is it Safe to Go Out?

If you are planning to go to a social event, consider how much close, skin-to-skin contact is likely to occur at the event. According to the CDC, there is some indication that events where people participate in close, sustained skin-to-skin contact have resulted in cases of monkey pox.

• Festivals, events and concerts where everyone is fully clothed and unlikely to engage in skin-to-skin contact are safer (although activities like kissing can increase risk).
• A rave, party or club where there is minimal clothing and where there is direct, personal, skin-to-skin contact has some risk. Avoid any rash you see on other people and consider minimizing skin-to-skin contact.
• Events in enclosed spaces, such as back rooms, sex clubs, saunas or sex parties (private or public) where intimate and possibly anonymous sexual contact occurs with multiple partners may carry a higher risk for spreading mpox.
• If you are experiencing symptoms of mpox or think (or know) that you have mpox, avoid gatherings, especially if they involve close, personal, skin-to-skin contact.

Consider having a conversation with your social groups too, particularly if you are planning to be in close personal contact. After more than two years of talking about health risks due to COVID-19, everyone is a little tired and burned out on the topic. But, as with COVID-19, being open about the degree of risk you’re willing to take can make it easier for everyone can enjoy their time together, with as little worry as possible.

Learn more about safer sex and social gatherings

If you have symptoms of mpox, speak with your healthcare provider, even if you do not think you had contact with someone with mpox. According to the CDC, you may be at higher risk if you:

• Were in close contact with someone diagnosed with confirmed or probable mpox or someone with a rash that looks like mpox
• Have had skin-to-skin contact with someone in a social group where mpox is spreading; this includes men who have sex with men (this could include people who are meeting at the same parties or through online dating apps)
• Traveled to another country with confirmed mpox cases or activity
• Were in contact with a live or dead animal that is native to Africa or used a product that has ingredients that come from that animal

While vaccines for the prevention of mpox are available, they are not currently recommended for the general public.

According to the World Health Organization, populations in some parts of the world have become more susceptible to mpox due to the discontinuation of routine smallpox vaccination, which has historically offered some cross protection.

Learn more

Sources

“Monkeypox,” Centers for Disease Control and Prevention, last modified June 17, 2022, https://www.cdc.gov/poxvirus/monkeypox/index.html

“Monkeypox (MPV),” Washington State Department of Health, last accessed December 9, 2022, https://doh.wa.gov/public-health-healthcare-providers/notifiable-conditions/rare-disease-public-health-significance/monkeypox

“Mpox (monkeypox),” World Health Organization, last accessed December 8, 2022, https://www.who.int/health-topics/monkeypox#tab=tab_1