A strain of drug-resistant gonorrhea has been detected in Massachusetts, prompting a worrying warning from the state’s Department of Public Health (DPH) on Thursday telling residents to take extra precautions. The strain is “the first time that resistance or reduced response to five classes of antibiotics has been identified in gonorrhea in the United States,” according to a statement from the DPH. At least two residents have been identified with the strain so far, but the cases appear to be unrelated and researchers are unable to find a direct connection. Contact tracing is currently underway to determine if other individuals have acquired the infection. The problem with gonorrhea, authorities said, is that it can present without symptoms, leaving those infected unaware if not tested. If left untreated, it can result in pelvic inflammatory disease, infertility, and other health problems. The two cases were eventually cured with ceftriaxone, the antibiotic currently recommended to treat gonorrhea. “The discovery of this strain of gonorrhea is a serious public health concern,” said Public Health Commissioner Margret Cooke. “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.”