Public Health Insider
Cases of mpox (formerly known as “monkeypox”) are on the rise in the Puget Sound region, including here in King County. Public Health is encouraging those who are eligible to get the two-shot mpox vaccine series.
Local spread of mpox
In September of this year, 45 new cases of mpox were reported in King County residents. This is the highest number of cases in a month since the initial mpox outbreak in King County in 2022. Increases in the number of mpox cases have also been reported in Chicago, San Francisco and New York.
While this number of cases is much lower than what we saw in 2022, when as many as 200 new cases of mpox were reported within one month in King County, the uptick highlights the need for those at risk to get vaccinated against mpox.
The majority of mpox cases in King County are associated with sexual and intimate contact among gay, bisexual, and other men who have sex with men, transgender people, and non-binary people. You can learn more about the demographics of those most impacted on our mpox data dashboard.
Who should get vaccinated?
Two doses of the mpox vaccine (name brand JYNNEOS) prevents most mpox infections and, if you do contract mpox, the vaccine is highly effective at preventing severe mpox disease. It takes about 2 weeks from the second dose to have the most protection.
Mpox vaccine can also be used to prevent infections and decrease the risk of severe disease in people following exposure to mpox. This requires that exposed people be vaccinated within 14 days of being exposed, ideally as soon as possible following contact with someone who has mpox.
Public Health recommends the following people receive two doses of mpox vaccine:
- Individuals who have had skin to skin or other close contact with someone with mpox.
- Gay, bisexual, and other men who have sex with men, as well as transgender/non-binary people who have sex with men or with other transgender/non-binary people.
- Individuals who have engaged in commercial and/or transactional sex in the past six months. For example, sex in exchange for money, shelter, food, or other goods or needs.
If you don’t meet the above criteria, you don’t need to get the mpox vaccine.
If you have only received one dose of the mpox vaccine, it’s not too late to get caught up — you do not need to restart the series.
If you’ve already received two doses of the mpox vaccine, or if you have previously had an mpox infection, you are considered immune to mpox and do not need to get another dose of the vaccine.
We particularly want to encourage young adults (ages 18-25) who meet the criteria above to get the mpox vaccine. People in this age group may not have been eligible to get vaccinated during the mpox outbreak in 2022.
Where to get the mpox vaccine
If you are at risk for mpox, contact your healthcare provider to see if they provide the mpox vaccine.
- Free vaccination is also available at Public Health’s Sexual Health Clinic at Harborview.
- For a complete list of clinics offering the mpox vaccination by appointment or walk-in, visit the mpox vaccination page.
Many health insurance plans, including Apple Health Medicaid, will cover the cost of the mpox vaccine for those who are eligible to receive the vaccine. If you don’t have health insurance, or if your insurance doesn’t cover the cost, Public Health’s Sexual Health Clinic at Harborview will provide the vaccine at no-cost to you, regardless of immigration or documentation status. The clinic can see you on a walk-in basis or you can make an appointment to be seen by calling 206-744-3950.
If you don’t have a healthcare provider, or need help accessing health insurance, contact Public Health’s Access and Outreach program at 1-800-756-5437 for help.
Ways to lower your risk of mpox infection
The single best way to prevent mpox infection is to get the two-dose mpox vaccine series.
In addition, the following behaviors can help reduce your risk of infection:
- Decreasing the number of sex and intimate contact partners.
- Avoiding venues where people wear minimal clothing and where there is direct skin-to-skin contact.
- Talking to your partner about new or unexplained sores or rashes on your body or your partner’s body, including rashes on the genitals and anus, and other symptoms and follow up with your provider if you suspect mpox or have questions.
Wearing condoms may offer partial protection because they help prevent skin-to skin contact, particularly if there are sores or rashes on the genitals or anus.
What is mpox and how does it spread?
Mpox is a viral infection that causes a skin rash and is sometimes accompanied by flu-like illness. The rash is often painful. Infections with the strain of mpox virus identified in King County are rarely fatal, and most people recover without treatment in 2-4 weeks.
Mpox is mostly spread through close physical contact with a person who has mpox virus infection. This includes direct contact with the mpox rash, scabs, or body fluids. In most cases, mpox is spread through sexual or intimate contact.
Though rare, mpox may sometimes be spread through contact with objects, fabrics (clothing, towels, or bedding), and surfaces that have been used by someone with mpox.
The mpox virus does not spread through the air. You cannot become infected with mpox just from breathing the same air as someone infected with mpox.
Types of mpox
There are two types of mpox, clade I and clade II. Both types of mpox primarily spread through close, skin-to-skin contact with a person with mpox.
The vast majority of mpox cases in the U.S. are clade II mpox infections.
There is currently a large, ongoing clade I mpox outbreak impacting many parts of central and eastern Africa. Clade I infections can be more severe than clade II.
No clade I infections have been reported in King County, and very few clade I infections have been reported outside of Central and East Africa. However, last month, health authorities in Pierce County identified signs of clade I mpox in the county’s wastewater. This indicates that someone with a clade I mpox infection may have been in Pierce County, although no case has been identified.
Two doses of mpox vaccine are highly effective in preventing clade II mpox. Current science indicates that the vaccine will also protect against clade I mpox, though data on how much the vaccine prevents clade I are very limited.
Additional resources
- Public Health’s mpox webpage
- Public Health’s Sexual Health Clinic at Harborview – no-cost mpox vaccine available to those at-risk of infection
- Washington State Department of Health mpox webpage
- Mpox infographics in English and Spanish
Originally published October 22, 2025.
