ST. LOUIS COUNTY, Mo. – Health officials have confirmed the first case of mpox in St. Louis County this year.

The St. Louis County Department of Public Health says the patient was a St. Louis County resident and likely contracted mpox through sexual contact. The patient was not previously vaccinated against mpox either.

Health officials are working to identify individuals with whom the patient may have been in contact while infectious. The county’s first case comes following a spike in mpox cases in the Chicago area that were confirmed last month.

Last year St. Louis County experienced a total of 42 known mpox cases, with the first case reported in late July and the last case reported in late November. The St. Louis County Health Department says the recent increase in mpox cases observed nationally suggests there is potential for renewed mpox outbreak in the St. Louis region. 

Mpox, renamed last year clinically referred to as orthopox, is in the same family of viruses as smallpox. Its symptoms are similar, though milder, to smallpox. It is important to know mpox can be fatal in rare instances. There are long-established vaccines and treatments for those infected.

According to the CDC, the mpox virus was discovered in 1958 in monkeys being kept for research. While the name of the virus is derived from its discovery, the actual source of mpox is unknown.

The first human case of mpox was recorded in 1970, in a child living in a remote rainforest of the Democratic Republic of the Congo.

Mpox symptoms will present anywhere between seven and 14 days after exposure. The disease itself lasts two to four weeks.

Symptoms include fever, headache, swollen lymph nodes, muscle ache, backache, chills, and exhaustion. Pimple or blister-like rashes will appear on an infected person’s face or inside their mouth and eventually spread across the body.

The virus can spread from the time symptoms first appear until the rashes themselves have fully healed.

Mpox is spread through person-to-person contact, including (but not limited to):

Direct contact with the infectious rash, scabs, or body fluids;

Respiratory secretions during prolonged, face-to-face contact, or during intimate physical contact, such as kissing, cuddling, or sex; and

Touching items (such as clothing or linens) that previously touched the infectious rash or body fluids.

Infected pregnant people can also spread the virus to their fetus through the placenta.