After a summer spike in mpox cases, public health officials are urging people to get vaccinated and take other precautions to keep the outbreak from growing.
Since Jan. 1, 71 Chicagoans have tested positive for mpox, with 59 (83%) of those cases happening since June 1, according to data maintained by the Chicago Department of Public Health (CDPH).
That same three-month period saw 46 cases in 2023 and 31 cases in 2024, according to CDPH.
Among the 59 cases in this year’s summer spike, there has been one hospitalization and no deaths, according to CDPH. Nearly half of those cases were among people who were unvaccinated.
“Many of these people have reported attending festivals like Pride events, and several have also reported anonymous sex,” said Stephanie Black, MD, a communicable disease medical director at CDPH. “What we’re wondering is if there are people who are perhaps new … to the community and have not been vaccinated.”
What is mpox?
Mpox is a viral infection that can cause a painful rash or sores that look like pimples or blisters on the face, body and genitals. It is often accompanied with flu-like illness, including fever, chills, head or muscle aches, or swelling of lymph nodes.
The virus is spread through close contact with bodily fluids, shared bedding or clothing, or respiratory droplets that can spread through kissing, coughing or sneezing.
Severe cases can require hospitalization, particularly for people living with other health conditions or those who are immunocompromised. None of the recent cases have required hospitalization, Black said.
Anyone can get mpox through close, personal contact with someone who has symptoms of the virus. But data suggests it has primarily spread among social networks of gay, bisexual and same-gender-loving men through intimate contact.
Risk is especially high for same gender-loving men who have multiple or anonymous sexual partners.
People experiencing mpox symptoms should contact their health care provider to get tested and isolate at home—or at least covering up areas where the rash is and washing hands frequently, Black said.
Those without a health care provider can access testing and treatment by calling the HIV and STI Resource Hub’s hotline at 1-844-482-4040.
The mpox vaccine
Vaccines have been a helpful tool in preventing the spread of mpox in Chicago since the recent global outbreak in 2022, Black said. The vaccine has proven to be about 75-86% effective after two doses and 58-75% after just one dose.
At this time, the Centers for Disease Control and Prevention (CDC) does not recommend a booster for people who were vaccinated during the 2022 outbreak, Black said.
The vaccine is recommended for:
- Bisexual, gay or other same-gender-loving men who are sexually active.
- Sexually active transgender people.
- People who have had skin-to-skin or intimate contact with someone who was diagnosed with mpox.
- Anyone living with HIV.
- People who are eligible or currently taking PrEP.
About half of people diagnosed with mpox this summer have been unvaccinated, Black said.
“So we really want to get the message out there about getting fully vaccinated to prevent mpox,” Black said.
People can get vaccinated against mpox for free at any of the city’s sexual health and immunization clinics.
CDPH’s sexual health clinics are located at:
- 2849 N. Clark St., 1st Floor
- 4909 W. Division St., Suite 411
- 200 E. 115th St., Floor 1.5
CDPH’s immunization clinics are located at:
- 4150 W. 55th St.
- 845 W. Wilson Ave, 2nd Level
- 1713 S. Ashland Ave.
- 200 E. 115th St., 2nd Floor
“And if people do get vaccinated, they should still be on the lookout,” Black said. “No vaccine is 100%, so if somebody has a rash, it might be good to delay close contact, sexual activity with that person.”