Mpox (Monkeypox)

(MPX)

Reviewed/Revised Apr 2023
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What is mpox?

Mpox is an infection caused by the monkeypox virus. The monkeypox virus is part of the same family of viruses as the virus that causes smallpox. But, mpox is less serious than smallpox. Mpox is not related to chicken pox.

  • Mpox can cause a rash that looks like pimples or blisters

  • Symptoms usually last 2 to 4 weeks

  • Mpox can spread to anyone through close, personal contact

  • Most cases of mpox don't need specific treatment, but some cases are treated with medicines

  • A vaccine to prevent mpox is available

  • Mpox is rarely fatal

In 2022, mpox cases were reported in countries that do not usually have mpox infections, but the number of new cases in the United States has dramatically decreased since the peak in August 2022. Before 2022, mpox most often caused disease in Central and West Africa.

What are the symptoms of mpox?

A rash is the most common symptom of mpox. The mpox rash:

  • May be painful or itchy

  • Begins as flat, red spots

  • Turns into raised blisters that look like pimples

  • Often starts on or near your genitals or in your mouth

  • Can also be on your hands, feet, chest, face, or mouth

  • Crusts and scabs over before healing

Other symptoms may occur before, during, or after the rash appears:

  • Fever

  • Chills

  • Headache

  • Muscle aches

  • Backache

  • Feeling extremely tired

  • Swollen lymph nodes (sometimes called "swollen glands")

Symptoms may start 1 to 3 weeks after you get infected. You can spread the virus to someone else from the time symptoms start. You stop being able to spread the virus once all lesions have crusted over, scabs have fallen off, and you have healthy skin where the scabs had been. This usually takes 2 to 4 weeks.

Mpox
Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image courtesy of the Public Health Image Library of the Centers for Disease Control and Prevention.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image from U.K. Health Security Agency.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image from U.K. Health Security Agency.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image from U.K. Health Security Agency.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image from U.K. Health Security Agency.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image from NHS England High Consequence Infectious Disease Network.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

Image from NHS England High Consequence Infectious Disease Network.

Mpox
Mpox
The rash of mpox resembles that of smallpox. Prior to the 2022 outbreak, the rash would often begin on the face and spr... read more

RICHARD USATINE MD / SCIENCE PHOTO LIBRARY

How can doctors tell if I have mpox?

If you have a rash that looks like a mpox rash, your doctor will have you tested for mpox.

The test is done on samples from the rash.

You may also have a blood test.

How do doctors treat mpox?

Most people recover fully within 2 to 4 weeks without treatment.

Doctors may treat your symptoms with pain medicines, fluids, and wound care to help you feel more comfortable.

Medicines that are used to treat smallpox may be given to people at higher risk of getting seriously ill from mpox. For example, medicines may be given to people who have a weak immune system.

How can I prevent mpox?

A vaccine to prevent mpox is available.

You should get vaccinated if you've been exposed to mpox.

Some people are at higher risk than other people of getting mpox. Higher risk people should get vaccinated, including people who:

  • Have been identified by public health officials as a contact of someone with mpox

  • Have had sex with someone who was diagnosed with mpox within the past 2 weeks

  • Had multiple sex partners in the past 2 weeks in an area with known mpox

  • Have jobs that may expose them to mpox, such as certain lab or healthcare workers

If you should get vaccinated, ask your doctor or local health department where you can find the vaccine.

If you have mpox, you should:

  • Stay at home and away from other people until a fresh layer of skin has formed where your scabs used to be

  • Avoid direct physical contact with other people and animals

  • Not share personal items, such as bed linens, towels, clothing, drinking glasses, or eating utensils

  • Clean and disinfect commonly touched surfaces and items

  • Wear a mask if close contact with others is necessary

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