Mpox

Mpox is a rare disease caused by infection with the mpox virus.¹ 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?

Mpox (previously called monkeypox) is a disease caused by the mpox virus, which belongs to the Orthopoxvirus genus.¹ 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, which is caused by an unrelated virus.

Mpox is a zoonotic disease, which means it is transmitted from animals to humans.² 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.

Types of Mpox

There are two types of mpox, clade I and clade II.1

• Clade I has historically caused more cases of severe illness than clade II, resulting in up to 10% of people dying from it, although recent outbreaks have had lower death rates of around 1-3%.¹
• Clade II caused the global outbreak that began in 2022. More than 99.9% of people who become infected with clade II survive.¹

Outbreaks

According to the CDC, in January 2023, an outbreak of clade I mpox was reported in the Democratic Republic of Congo (DRC).1 While clade I occurs regularly in the DRC, this outbreak is more widespread than any previous outbreak and has spread to several neighboring countries, with one travel-associated case in Kenya. On Aug. 14, 2024, the World Health Organization (WHO) declared the outbreak a Public Health Emergency of International Concern (PHEIC). Declaration of a PHEIC recognizes the threat a virus may pose to populations worldwide.

In November 2024, the first case of clade I mpox in the United States was identified in California. The patient has since recovered. No additional cases have been reported.

The global outbreak that began in 2022 was caused by clade II mpox.³ That outbreak is ongoing, although the outbreak peaked in the United States in July and August 2022, with around 11,000 cases per month.

Since October 2023, monthly case counts have been consistent at about 250 per month nationally. In 2023, there were about 1,700 cases nationwide. As of Sept. 6, 2024, the CDC estimated that 1,900 cases had been reported.³

Before 2022, the last mpox outbreak in the United States occurred in 2003.⁴ 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.³ 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.

Visit the Centers for Disease Control and Prevention website for more information:

• Mpox in the United States and Around the World: Current Situation
• Ongoing Clade II Mpox Global Outbreak

Symptoms

The incubation period for mpox ranges from 3 to 17 days.⁵ During this time, a person does not have symptoms. Symptoms typically start within 21 days of exposure to the virus.⁵

Mpox infections often cause a pimple- or blister-like rash that may appear on the genitals (penis, testicles, labia and vagina) or the anus, but could also be on areas such as the hands, feet, chest, face or mouth.⁵ The rash can be painful or itchy and will go through several phases, including scabbing, before it heals. In cases of infection during anal sex, infected individuals may experience anal or rectal irritation.

Symptoms can also include the following⁵:

• Fever
• Headache
• Muscle aches and backache
• Swollen lymph nodes
• Chills
• Exhaustion
• Respiratory symptoms, such as sore throat, nasal congestion or cough

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.⁵

• 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 later⁵
• 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.⁶ The disease can be more serious in people who are pregnant, children or immunocompromised.

Transmission—How Mpox Spreads

Mpox can spread to anyone through close personal contact, including the following routes⁷:

• Direct contact with an infected rash or scabs from a person with mpox
• Contact with saliva, upper respiratory secretions (snot or mucus) and bodily fluids or lesions around the anus, rectum, or vagina from a person with mpox
• From a pregnant person to the fetus through the placenta

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.⁵ In addition, new evidence suggests that mpox can be spread to others from 1 to 4 days before symptoms appear.

Close personal contact includes⁷:

• 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 (talking, breathing)

Indirect Contact

Mpox can also spread when a person touches fabrics and objects that have not been disinfected after use by someone with mpox. This includes bedding, towels, fetish gear and sex toys.⁷

Scientists are still learning about⁷:

• Whether the virus spreads when someone has no symptoms
• How often it’s spread 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.²

Mpox can also be spread from humans to animals, although medical experts are still learning which animals can get mpox. Researchers do not know if pets like dogs and cats can be infected with mpox, but it may be possible through close contact such as petting, cuddling, hugging, kissing, and sharing sleeping areas or food.⁷

Learn more:

• Centers for Disease Control and Prevention Mpox in Animals and Pets
• Washington State Department of Health Guidance on Mpox and 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.⁸

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.⁹ Patients may be recommended an antiviral like tecovirimat (TPOXX), which is approved by the FDA for the treatment of smallpox. Patients who are more likely to get severely ill with mpox would be prioritized for treatment with TPOXX.

Vaccines

The JYNNEOS vaccine is an FDA-approved vaccine for the prevention of mpox and smallpox. This is a two-dose vaccine, administered four weeks apart.¹⁰ Both doses should be received for the best protection. If you have only received one dose of the vaccine and it has been longer than four weeks, you should still get your second dose.

Where to Get an Mpox Vaccination

• Find mpox vaccines near you at mpoxvaccine.cdc.gov
• Contact Consistent Care Spokane, your local pharmacy, or your health care provider.

See the FAQ to learn more about the JYNNEOS vaccine.

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 resulted in 654 cases of mpox in Washington state and 10 in Spokane County.¹¹ For the latest information and case numbers in Washington state, please see the following resources:

• Washington State Department of Health Mpox

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.

Get Vaccinated

Talk with your health care provider or pharmacist about getting the JYNNEOS vaccine if you think you are at risk. The vaccine is effective at preventing mpox and reducing severity of symptoms if you do become infected.

Learn more about who should get the vaccine

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.

Social Gatherings

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, events where people participate in close, sustained skin-to-skin contact have greater risk.¹²

• 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).¹²
• 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.¹²
• 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.¹²
• 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.¹²

Consider having a conversation with your social groups too, particularly if you are planning to be in close personal contact. 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 Think You Have Symptoms of Mpox

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

• Are a health care worker at risk of exposure
• Live in the same household with someone who has mpox
• Have multiple sex partners, including men who have sex with men
• Are a sex worker or if you have close, intimate contact with a sex worker

• Centers for Disease Control and Prevention Mpox
• Washington State Department of Health Mpox
• World Health Organization Mpox