U.S. investigating first cases of "concerning" new drug-resistant gonorrhea strain
Health authorities in Massachusetts announced Thursday they have identified two cases of a new strain of gonorrhea that appears to have developed resistance to a broad swath of antibiotic treatments.
Both patients got better after getting injections of ceftriaxone, the main drug currently recommended to treat cases of the sexually transmitted infection. But state health officials warn the strain that infected them shows signs of at least some resistance to almost every drug to treat the bacteria, the first of its kind confirmed in the U.S. to date.
Investigators are now working with the Centers for Disease Control and Prevention to test other samples collected from gonorrhea cases in the state. Massachusetts is also conducting contact tracing to find out if the drug-resistant strain has spread to others.
"The discovery of this strain of gonorrhea is a serious public health concern which DPH, the CDC, and other health departments have been vigilant about detecting," Margret Cooke, head of the Massachusetts Department of Public Health, said Thursday in a statement.
Gonorrhea is the second most common sexually transmitted infection reported to health authorities in the U.S., behind chlamydia, according to the CDC.
Many who are infected by the bacteria often have little to no symptoms. However, some can develop bleeding, discharge, and more serious complications that can lead to infertility and pain.
The initial case was identified in a patient who went to a primary care clinic with symptoms of urethritis, a kind of irritation that can make it difficult to urinate. Samples examined by the state's health laboratory flagged a "concerning" pattern later verified by follow-up testing by the CDC.
A spokesperson for the state declined to clarify additional details about the two cases, beyond those identified in the department's announcement and alert to providers.
No direct connection has been identified between the two cases. One had no recent travel history, suggesting the strain could be spreading within the state.
"We urge all sexually active people to be regularly tested for sexually transmitted infections and to consider reducing the number of their sexual partners and increasing their use of condoms when having sex," Cooke said.
Gonorrhea's "alarming" drug resistance
For years, health authorities have been working to respond to the "alarming" ability that gonorrhea has to develop resistance against antibiotics that have been deployed to combat it.
In 2013, the CDC named gonorrhea as one of the three most urgent threats posed by antibiotic-resistant bacteria. Both U.S. and world health authorities have launched campaigns to curb new cases of gonorrhea in hopes of controlling the bacteria until vaccines and new treatments are developed.
The Massachusetts cases are the first confirmed in the lab to have developed the ability to sidestep six of the seven drugs that health authorities track for potential resistance. It carries a change to the "penA60 allele" – a gene mutation – which has been linked to previous ceftriaxone-resistant cases in Nevada, the United Kingdom, and Asia.
"This case is a reminder that antimicrobial-resistant gonorrhea remains an urgent public health threat nationally and internationally; all providers in all clinical settings need to remain vigilant," Dr. Laura Hinkle Bachmann, chief medical officer of the CDC Division of STD Prevention, said Thursday in a letter to providers.
Ceftriaxone injections, boosted with other oral antibiotics like azithromycin and doxycycline, have been the last recommended treatment for gonorrhea since 2012. At the time, laboratory data showed a related drug known as cefixime had been losing effectiveness and risked creating resistance to ceftriaxone too.
Only one drug tested against the Massachusetts strain by the CDC's panel – gentamicin – showed no sign of reduced susceptibility. However, that drug is already generally considered a less effective treatment for gonorrhea.
Scientists have pursued new drugs for gonorrhea like zoliflodacin, which showed promising early results in a 2018 study backed by the National Institutes of Health. That drug is currently being studied in clinical trials and has not been approved by the Food and Drug Administration for gonorrhea.
"Timely identification and treatment, as well as rapid public health response, are essential to keeping patients safe and reducing the risk of community transmission. We must all remain alert for potential gonococcal treatment failures as we combat the growing threat of antimicrobial resistance," Bachmann said.