The case follows an increase in mpox cases in the Chicago area, which saw more than two dozen cases in April and early May.

“This year’s first case serves as a reminder for us in St. Louis County and surrounding areas to take action to protect ourselves. This includes getting two doses of the Jynneos vaccine if you are eligible, and paying attention to your own health and that of your partners,” the St. Louis County Department of Public Health stated in its report.

Vaccination against the virus, formerly known as monkeypox, requires two doses given two weeks apart. Those who are vaccinated can still get infected, but they will be less likely to experience severe symptoms and end up in the hospital, studies have shown.

The infected St. Louis County resident was not vaccinated and likely contracted mpox during sexual contact, health officials said.

The county health department is working with the Missouri Department of Health and Senior Services to identify the person’s contacts in an effort to stop transmission of the virus and prevent a wider outbreak.

This is the tenth mpox case reported so far this year in Missouri, said DHSS spokeswoman Lisa Cox. Federal data shows 224 cases have been reported in Missouri since the nationwide outbreak began.

Mpox is transmitted between individuals who have prolonged intimate contact. Infections have been primarily reported among men who have sex with men, but any person — regardless of sexual orientation — can contract and spread the virus.

Symptoms include fever, chills, head or muscle aches, followed by a rash that looks like pimples, sores or blisters. The sores can be painful or itchy and may first appear in the genital area.

Early detection is key in preventing the spread. If experiencing any symptoms, contact your health care provider or the county health department at 314-615-2660.

Avoid skin-to-skin contact with people who have a rash in the genital regions, hands, feet, chest or mouth, health officials warned. Anyone who only received one vaccine dose is also encouraged to get the second.

Data shows many may have skipped the second shot. Residents of St. Louis have received 1,493 first doses and only 1,107 second doses, according Cox. County residents have received 985 first doses and 559 second doses.

A list of places to get tested and vaccinated is available on the city and county’s health department websites. Health officials will also provide vaccines this Saturday and Sunday in a section called “the HIVE” at PrideFest in downtown St. Louis.

Last year St. Louis County reported a total of 42 mpox cases, with the first case reported in late July and the last case reported in late November.

The city of St. Louis saw 72 cases, according the city’s website. The city also saw its first case last July.

Across the country, more than 30,500 mpox cases have been reported since last May and 43 deaths, according to the CDC.