Mpox

What is mpox?

Mpox (previously known as monkeypox) is a disease caused by a virus. It usually causes a rash and flu-like symptoms. The rash is similar to the one caused by a related virus, smallpox.

Cases of mpox happen regularly (it’s endemic) in parts of Africa. But outbreaks sometimes happen in other places around the world. An outbreak is an increase in cases, or a larger-than-expected number of cases.

Types of mpox

There are two known subtypes of mpox:

• Clade I. Clade I is endemic to Central Africa. It tends to cause more serious illness than clade II. Recent outbreaks of clade I have been less deadly. 
• Clade II. Clade II is endemic to East Africa. There’s been a global outbreak of clade II mpox since 2022. It’s less likely to be fatal than clade I. 

Outbreaks

Since 2023, there’s been an outbreak of clade I mpox in Central and East Africa.

Since 2022, there’s been an ongoing outbreak of clade II mpox affecting countries around the world. There were 1,700 reported cases in the U.S. in 2023. In total, there’ve been over 102,000 reported cases of clade II mpox worldwide since 2022.

The last outbreak in the U.S. before this was in 2003. Forty-seven people in six states were infected with mpox from pet prairie dogs. It wasn’t spread from person to person.

What are the symptoms of mpox?

Symptoms of mpox include:

• Rash, skin ulcers or blisters.
• Fever.
• Swollen lymph nodes.
• Chills.
• Headache.
• Muscle aches.
• Fatigue.

Not everyone with mpox develops all the symptoms. Different ways you might experience symptoms include:

• Only a rash (no other symptoms), or other symptoms developing later.
• Flu-like symptoms, then a rash. Some people don’t get a rash at all.

What does the mpox rash look like?

The rash caused by mpox can appear as sores on your mouth, face, hands, feet, penis, vagina or anus (butthole). Some people have a widespread rash, but others only a have few bumps or blisters.

Mpox rash can go through several stages over two to four weeks:

1. It may start out as flat, red bumps. These can be painful.
2. The bumps become raised.
3. The bumps turn into blisters.
4. The blisters fill with pus.
5. The blisters crust over and fall off.

What causes mpox?

An infection with monkeypox virus (Orthopoxvirus monkeypox) causes mpox. Viruses are small pieces of genetic information in a protective coating. The virus that causes mpox is a pox virus, and a member of the genus Orthopoxvirus.

How do you get mpox?

Mpox can spread through:

• Direct contact with mpox sores or scabs (from an animal or person).
• Contact with saliva (spit), respiratory secretions from your nose or mouth (mucus), blood or other bodily fluids (from an animal or person).
• Contact with materials like clothing, bedding and towels used by a person or animal who’s infected.
• Vertical transmission — from a pregnant person to their fetus during pregnancy or at birth.

Specific situations that can spread mpox include:

• Close, intimate contact, like cuddling, kissing or sex. It’s possible, though less likely, that you could spread mpox by talking, sneezing or coughing very close to others.
• Skin-to-skin contact.
• Sharing personal items, like towels, bedding or sex toys.
• Bites or scratches from an infected animal.
• Eating the meat of an infected animal.

What are the risk factors for mpox?

Anyone can get mpox. The global outbreak appears to be disproportionately affecting men who have sex with men (MSM). On the other hand, in the clade I outbreak in the Democratic Republic of Congo, children under 15 years old make up more than half the cases.

In the U.S., you might be at a higher risk of exposure if:

• Someone you’ve had sex with in the past two weeks has been diagnosed with mpox.
• You’ve had sex at a sex club, bathhouse or another commercial sex venue in the past six months.
• You’ve had sex at an event or location where mpox was spreading.
• You have a sex partner who’s been in any of the above situations.
• You’ve been diagnosed with one or more sexually transmitted infections (STIs) in the past six months. This includes acute HIV, gonorrhea, syphilis, chancroid or chlamydia.
• You’ve had sex with more than one person in the past six months.

You might be more likely to get severely ill with mpox if you:

• Have a weakened immune system, especially if it’s caused by HIV.
• Have a history of eczema.
• Are pregnant.

Babies younger than 1 year old are also at a higher risk for severe illness.

What are the complications of mpox?

Complications caused by mpox can include:

• Bacterial infections, which can lead to sepsis.
• Loss of vision or eye damage from mpox ocular infections.
• Myopericarditis (inflammation around your heart).
• Encephalitis (inflammation in your brain).
• Pneumonia.
• Respiratory distress (extreme difficulty breathing and getting oxygen to your body).
• Severe scarring.

How is mpox diagnosed?

To diagnose mpox, your healthcare provider will swab two to three sores (lesions). They’ll send the samples to a lab for polymerase chain reaction (PCR) testing. They may also do blood tests.

It’s important to let your provider know if you may have been exposed to mpox. Your provider might test you for other illness that cause a rash, like measles or chickenpox.

How is mpox treated?

There aren’t any approved antiviral treatments for mpox. If you’re very sick or if you’re pregnant, your provider might treat you with antiviral drugs, like tecovirimat (TPOXX) or cidofovir/brincidofovir. Vaccinia immune globulin (VIG-IV), a type of antibody treatment, is also sometimes an option.

These drugs are approved to treat other viral infections (like smallpox) and could benefit some people. But researchers are still studying how well they work for mpox.

How can I prevent mpox?

The best way to reduce your risk of mpox is to get vaccinated if you’re at a higher risk of exposure. It’s important to get vaccinated before, or as soon as possible after, exposure. 

In addition to vaccines, other ways to help prevent the spread of mpox include:

• Avoiding close contact in social situations (like clubs, raves or parties), especially if you or other people have a lot of exposed skin.
• Not touching mpox rashes, blisters or scabs.
• Avoiding contact with bedding and other materials that could be contaminated with mpox.
• Washing your hands frequently with soap and water.
• Practicing safe sex, including the use of condoms and dental dams.
• Wearing a mask that covers your mouth and nose when around others.
• Cleaning and disinfecting frequently touched surfaces.
• Using personal protective equipment (PPE), like gloves and a mask, when caring for people with mpox.
• Avoiding contact with infected animals or wild animals.
• Thoroughly cooking all foods that contain meat and not eating the meat of wild animals.

You can have mpox and not know it. Even if you don’t show many signs of infection, it’s possible that you can still spread it to others through prolonged, close contact.

Who should get vaccinated for mpox?

Mpox vaccines are currently only recommended for people who’ve been exposed to, or are likely to be exposed to, mpox. Recommendations for getting mpox vaccines are based on who’s at a higher risk. These risks might be different depending on where you live or travel to.

In the U.S., people 18 and older who have risk factors should receive two doses of the JYNNEOS™ vaccine 28 days apart. Generally, you’re at risk if you have a known or suspected exposure to someone with mpox or are in situations that could expose you to mpox.

Check your local public health official for recommendations — for example, the Centers for Disease Control and Prevention (CDC) in the U.S. Talk to a healthcare provider if you’re wondering if you should get vaccinated.

How does mpox vaccination work?

A provider will give you two doses of mpox vaccine at least 28 days apart. The vaccine is a shot. A provider can give it either as an intradermal vaccination (between the top layers of your skin) or subcutaneous vaccination (injected into the fat under your skin).

The intradermal vaccination may leave a scar. If you’d like to get your shot in a more concealed location on your body, your provider can give it to you in your shoulder blade instead of your forearm. You can also request a subcutaneous vaccination.

What happens if you have mpox?

Mpox normally takes about two to four weeks to run its course. Your provider will monitor you until the rash resolves.

Can you survive mpox?

Clade II mpox — the subtype causing a global outbreak — is rarely fatal. The fatality (death) rate for clade I has historically been around 10%. But during recent outbreaks, it’s been less than 3.3%.

How do I take care of myself?

If you have mpox symptoms, you can take care of yourself at home with:

• Over-the-counter (OTC) medications. Medicines like ibuprofen and acetaminophen can help relieve your symptoms.
• Colloidal oatmeal baths. Soaking in a warm bath with colloidal oatmeal products can relieve the dry, itchy feeling that comes with skin rashes.
• Rest and fluids. It’s important to stay home, rest and drink plenty of fluids to help you recover.

You can also reduce the risk of spreading mpox and take care of others by:

• Isolating yourself if you’re infected. Avoid contact with others until your skin has healed.
• Wearing a mask. If you have to be around others — for instance, to seek medical care — wear an N95 or KN95 respirator mask that covers your mouth and nose.
• Covering small areas of ulcers or sores. Use gauze or bandages to limit the spread to others and items you touch.
• Avoiding contact with pets (especially rodents). Mpox can be transmitted between humans and animals.

When should I see my healthcare provider?

Talk to your healthcare provider if you:

• Feel sick with fever, aches or swollen lymph nodes.
• Have a new rash or sores.
• Have been in close contact with a person who has mpox.
• Want to learn more about or find out where to get the mpox vaccine.

If you’re pregnant, let your pregnancy care provider know right away if you’ve been exposed to mpox or have symptoms. They can help you reduce your risk of severe illness and passing mpox to the fetus during pregnancy and birth.

When should I go to the ER?

Go to the emergency room or call 911 (or your local emergency services number) if you experience:

• Trouble breathing or severe shortness of breath.
• New or worsening chest pain.
• Neck stiffness.
• Confusion or difficulty thinking clearly.
• Difficulty speaking or moving.
• Loss of consciousness.
• Seizures.
• A wound that’s not healing or is very painful.

What questions should I ask my healthcare provider?

It might be helpful to ask your healthcare provider:

• Should I get vaccinated?
• Are there any treatments available?
• How do I take care of myself at home?
• Which serious symptoms should I look out for?

Why don’t we call it monkeypox anymore?

The World Health Organization (WHO) changed the name to mpox in November 2022. This aligns it with the WHO’s current recommendations for naming diseases in a way that avoids stigmas. The virus that causes mpox is still called monkeypox virus.

What’s the difference?

Mpox vs. chickenpox

Although they both cause skin rashes, different viruses cause mpox and chickenpox. Mpox is an orthopoxvirus, while chickenpox is a herpes virus. Both viruses can spread through skin-to-skin or prolonged face-to-face contact, but chickenpox is very contagious and spreads more easily than mpox. People with mpox are more likely to have swollen lymph nodes than people with chickenpox.

The rashes act differently, too. While the chickenpox rash can appear in waves, mpox sores develop at the same time. Chickenpox symptoms — including the rash — tend to get better within two weeks, while it takes two to four weeks for mpox to resolve.

Mpox vs. smallpox

Smallpox and mpox are both part of the Orthopoxvirus genus, so they’re caused by similar but distinct viruses. Thanks to effective vaccines, smallpox was eradicated (is no longer a circulating disease) by 1980. Smallpox was very contagious and spread more easily than mpox. Mpox symptoms are similar to smallpox, but milder.