Group B Streptococcus can cause sepsis in newborns and severe infections in elderly or immunocompromised adults — and researchers recently uncovered a new mutation in GBS that makes it more resistant to antibiotics.
The research was presented at the CDC's 66th Annual Epidemic Intelligence Services Conference this week.
Researchers obtained 2,257 samples from invasive GBS infections and then used two types of tests to determine if the samples exhibited antibiotic resistance. They also used a whole genome sequencing pipeline to see if the resistant strains matched known determinants of resistance.
They identified 520 highly resistant samples and three resistant strains that did not match a pipeline-predicted resistance mechanism. Two of those three strains were from Georgia and showed a mutation on one site of the gene.
"We report the emergence of a mutation in the 23S gene in two GBS strains, undetected by our current pipeline," the study concludes. "To our knowledge, this mutation has not previously been detected in GBS, highlighting the value of joint phenotypic and WGS testing for timely detection of emerging resistance-associated mutations."
Researchers have not yet found the resistance mechanism exhibited by the third strain.