Cases of infectious syphilis have declined nearly 30% in Michigan since 2021. But cases of infants born with the disease -called congenital syphilis - have not declined.
Since 2021, congenital syphilis cases have increased 38%, according to the Michigan Department of Health and Human Services, leveling off in recent years with 55 births in 2023, 58 in 2024 and an expected 50 to 60 births in 2025.
Untreated, babies can suffer serious and life threatening conditions from syphilis.
James Kent is the state's sexually transmitted infection epidemiologist. He said there could be many reasons for the relatively stable number of cases involving babies in recent years.
One is that some mothers are getting no pre-natal care. State law requires a mother to be tested for syphilis at her first pre-natal appointment.
Or, Kent said, some mothers can't adhere to the treatment schedule. It generally requires a series of three Penicillin G injections, on the same day a week apart, plus follow-up testing.
"Congenital syphilis is preventable," Kent said. "But it's a question of detection. The mother has to be tested for syphilis, diagnosed and treated before [the baby's] birth.
MDHHS said rates of other sexually transmitted infections, including chlamydia and gonerrhea, have also been on the decline since 2021.
But despite the recent good news for infectious syphilis, Michigan’s overall syphilis rates remain historically high compared to a decade ago. Nationally and in Michigan, rates rose sharply between 2014 and 2021.
MDHHS attributes its recent success in reducing infectious syphilis to its partners across the state, including clinicians in local health departments and other health care settings, community-based organizations, social services agencies, correctional facilities, and pharmacies.
MDHHS says it has invested in rapid syphilis testing, media campaigns, provider outreach and education, enhanced partner services and follow-up for women of child-bearing age with syphilis, as well as biomedical interventions such as doxycycline post-exposure prophylaxis.
