Nearly all isolates of the bacterium that causes syphilis bear mutations that make them resistant to the antibiotic azithromycin, according to a study of samples collected from the United States and Canada.
The findings were reported June 12 in the New England Journal of Medicine. Nicole Lieberman, a senior scientist in laboratory medicine and pathology at the University of Washington School of Medicine, is first author. Dr. Alex Greninger, associate professor in the department, led the study.
U.S. syphilis cases have surged. Cases nearly doubled from 114,000 in 2018 to more than 203,000 in 2022. Of particular concern is the growing number of infants born with congenital syphilis, which can have devastating consequences including vision loss, physical deformities and neurological damage.
