According to researchers, a certain bacterial strain has acquired a new gene that makes it able to resist antibiotics via the DNA sequence known as CRISPR, clustered regularly interspaced short palindromic repeats (not to be confused with the CRISPR gene-editing technology).
“Bacteria acquire CRISPR sequences from infecting viruses called bacteriophages, which insert fragments of DNA into bacterial genomes,” the University of Washington School of Medicine, which was involved in the study, reported in a news release explaining how bacteria get these pieces of DNA via viral infection. (Yes, even bacteria can get a viral infection.) These bacteriophages hijack their host system to reproduce and can leave bits of DNA behind. “In this case the CRISPR sequence appears to have included the drug-resistance gene.”
The recent study, led by Dr. Alex Greninger, assistant professor of laboratory medicine at the UW School of Medicine, discovered nearly identical bacteria among these unrelated men in the two cities, and concluded it is likely being transmitted by men who have sex with men.
Campylobacter is one of the most common causes of diarrhea around the world. In fact, according to a Centers for Disease Control and Prevention estimate, it causes 1.5 million illnesses in the United States every year. People usually recover without treatment, but those with serious cases or compromised health require antibiotics. What makes this new strain particularly dangerous is that it is resistant to those antibiotics used for treatment.
“Enteric infections can be sexually transmitted infections,” Greninger said in the press release, about the intestinal infections that can be transmitted via anal intercourse, rimming, or other sexual practices. “The international spread of related isolates among MSM populations has been shown before for Shigella, so it makes sense to see it in Campylobacter as well.” The group of bacteria called Shigella cause about 500,000 cases of diarrhea in the United States annually, and outbreaks among gay and bisexual men have been noted for two decades.
Men who have sex with men are at higher risk of multidrug resistance because they’re more likely to have taken antibiotics to treat past STIs, the authors of the new study state. According to MedScape, Campylobacter infections may be more common and cause prolonged or recurrent diarrhea among those living with HIV.
While STI rates have increased significantly over the last few years, less is known about STIs related to intestinal bacteria. This outbreak among gay and bisexual men with a strain that is resistant to antibiotics raises the stakes.
“The global emergence of multidrug-resistant enteric pathogens in MSM poses an urgent public health challenge that may require new approaches for surveillance and prevention,” the authors concluded.