Current Status of Mpox in California

On November 15, 2024, the California Department of Public Health (CDPH) confirmed​ the first known case of clade I mpox (formerly known as monkeypox) in the United States​. This individual had recently traveled to a region in Africa where there has been an ongoing clade I mpox outbreak. At this time, there is no concern or evidence that clade I mpox is currently spreading between individuals in California or the United States. The risk to the general public remains low. ​

There are two types of mpox: clade I and clade II. Clade II mpox has been circulating in the U.S. and California since 2022. There has been an ongoing outbreak of clade I in certain regions of Africa.​ Other travel-associated cases have also recently been found in Europe and Asia. 

If you are traveling to areas with clade I mpox, see CDC Preventing Mpox While Traveling​. Preventive measures, including the mpox vaccine, are expected to be protective against both clade I and clade II mpox. Individuals who may be at risk for mpox​ are encouraged to make sure they have received both doses of the mpox vaccine. 

At this time, mpox vaccine is still not recommended for the general public, individuals who already received two doses of mpox vaccine, or individuals who have had mpox in the past.

For more information about mpox, see CDPH Mpox Questions and Answers (Q&A). For data about reported mpox cases in California, see CDPH Mpox Data​. ​

Mpox Overview

​Basic information is shown below. Information about prevention, symptoms, and treatment apply to both types of mpox. For more details, see CDPH Mpox Questions and Answers (Q&A). Information for health care professionals can be found at CDPH Mpox Guidance.

What is mpox?

Mpox is an infection caused by the monkeypox (mpox) virus. It mainly spreads through close, personal, skin-to-skin contact with people who have mpox rashes and sores. Casual contact, like one might have during travel, in an office, classroom or store, is unlikely to pose significant risks for transmission of mpox. 

Anyone can become infected with mpox if they are exposed. Mpox is usually a mild infection with symptoms lasting from 2 to 4 weeks. But it can cause severe illness and very rarely, death. There is a vaccine to protect against mpox. 

Is mpox a new virus?

No. Mpox was first discovered in 1958 and is regularly found in west and central Africa. There are two types of the virus: clade I and clade II. Since 2022, there has been a global outbreak of clade II mpox and it has continued to spread at low levels—including within the U.S. and California. This type has primarily spread through sexual contact and causes more mild illness than clade I mpox.

There is an ongoing clade I mpox outbreak in certain regions of Africa. The first case of clade I mpox identified in the U.S. was in a traveler who had recently returned from an area where clade I mpox has been spreading. Other travel-associated cases have recently been found in Europe and Asia. Clade I mpox may spread more easily and cause more severe illness than clade II mpox. However, recent outbreaks in Africa suggest that illness severity may be more similar to the current circulating type in the United States, especially when appropriate supportive medical care is provided.​

What are the symptoms?

Mpox can start with symptoms such as a fever, low energy, swollen lymph nodes, and general body aches. Within about 3 days, a rash or sores develop. People with mpox may experience all or only a few of these symptoms.

The rash or sores can look like pimples or blisters and may be painful and itchy. The rash or sores may be located anywhere on the body, including on or near the genitals (penis, testicles, labia, and vagina) or anus (butt). The sores go through several stages, including scabs, before healing.

How does mpox spread?

Mpox is mainly spread through close contact with people who have symptoms. Mpox can be spread by:

• ​Direct skin-to-skin contact with the sores or scabs.
• Direct contact with body fluids. This may include drainage from skin sores or saliva that was in contact with mouth sores.
• Contact with saliva, snot, or mucous during prolonged, face-to-face contact.
• Intimate physical contact, such as kissing, cuddling, or sex.
• Touching items used by people with mpox, such as bedding, towels, clothes, cups, and utensils.
• ​Transmission from a pregnant person with mpox to the fetus or baby.

A person with mpox can spread it to others before symptoms start until all sores have healed (scabs have fallen off and a fresh layer of skin has formed). This may take several weeks.

See CDC | How Mpox Spreads and CDPH Mpox Q&A​ for more information.

How is mpox prevented?

There are actions you can take to prevent the spread of mpox in the community:

• Get vaccinated to protect yourself if you may be at risk for mpox. For the greatest protection, make sure you get both doses of the vaccine. Find mpox vaccine (JYNNEOS) near you​.
• Talk to your sexual partner(s). Ask about recent illnesses. Be aware of new or unexplained sores or rashes on you or your partner.
• Avoid skin-to-skin contact such as hugging, kissing, cuddling, and sexual activity with those who have a rash or sores that look like mpox.
• Do not share items such as towels, fetish gear, sex toys, and toothbrushes with someone who has mpox.
• Wash your hands often with soap and water or an alcohol-based hand sanitizer.
• Protect yourself when caring for someone with mpox by using masks, gowns, and gloves.
• If you were exposed to mpox, take precautions. Get the mpox vaccine before symptoms develop and consider avoiding intimate contact with others for 21 days. Watch yourself for symptoms and get tested if they develop.
• ​If you have been told you have mpox, prevent spread to others. Avoid contact with others until the rash is healed, clean and disinfect shared areas in the home, and notify people who may have been exposed.

What do I do if I was exposed?

• Get vaccinated before symptoms develop. If you haven’t already been vaccinated, getting the vaccine after exposure may still provide some protection. The mpox vaccine can prevent mpox infection if given within 4 days of the exposure. If given 4-14 days after the exposure, the vaccine may not prevent an infection but may still prevent severe symptoms. Find a vaccinating provider near you.
• Take precautions. Watch yourself for symptoms and consider avoiding close or intimate contact with others for 21 days after exposure.
• ​Get tested for mpox if you notice any rash or sores.

See CDC If You’re a Close Contact for more information.

I got infected. What do I do now?

• Ask about treatment. Most mpox infections are mild and heal without any treatment. Talk to your health care provider about medications for your symptoms and skin care advice to promote healing.
• Antiviral drugs, such as tecovirimat (TPOXX), may be used to treat mpox. It is recommended for people ​​who are very ill or are more likely to become very ill. For more information on TPOXX, see Treatment Options on CDPH Q&A and CDC Patient's Guide for Tecovirimat.
• Prevent spread to others.
• Isolate from others until the rash is healed.
• Clean and disinfect shared areas in the home.
• ​Notify close contacts who may have been exposed. Consider using TellYourPartner.org, an anonymous texting service available in English and Spanish.

See CDC | What to Do If You are Sick for more information.​​​​​​​​​​​​​​​