Gonorrhea has progressively developed resistance to the various antibiotic drugs prescribed to treat it. Following a strong track record for the latest recommended gonorrhea drug, fresh data from 2014 suggests these improvements may be “short-lived,” according to a Centers for Disease Control and Prevention (CDC) study.

Gonorrhea, or the infectious bacteria Neisseria gonorrhoeae, is a common sexually transmitted disease and the second most common communicable disease, according to the CDC. An estimated 820,000 new gonorrhea infections occur each year in the United States. While for men gonorrhea infections cause obvious symptoms inspiring them to seek treatment, an infection in women may be asymptomatic or difficult to detect until complications have occurred. As a result, a woman who misses the earliest signs of infection may experience any number of general health or reproductive complications, including infertility.

However, treatment itself is a complex matter. In the past, recommended gonorrhea drugs have developed antimicrobial resistance over time. To ensure effective treatment, then, the CDC monitors resistance trends and, based on what it discovers, periodically updates its drug guidelines.

Running from Resistance

In recent years, the cephalosporin antibiotics have been the foundation of treatment. Specifically, in 2010 the CDC recommended a higher dose of cephalosporin (injectable ceftriaxone or oral cefixime) plus a second antimicrobial. Then in 2012, the CDC updated its guidelines again, recommending only the ceftriaxone combination therapy.

Since general resistance to antibiotics means the war chest of effective medicines is gradually dwindling, the emergence of cephalosporin-resistant gonorrhea would reduce medicine’s ability to treat gonorrhea successfully. For this reason, health officials looked at the latest resistance data.

Dr. Robert D. Kirkcaldy of the CDC and his colleagues examined gonorrhea susceptibility trends between the years 2006 and 2014. When antibiotics kill or stop the growth of a certain bacteria in the laboratory, the bacteria is known as susceptible to antibiotics. The researchers analyzed data from the Gonococcal Isolate Surveillance Project, a system that monitors isolates (bacterial samples) from patients with gonorrhea who were treated at public clinics for sexually transmitted disease.

During 2006-2014, 51,144 isolates were collected in 34 cities. The percentage of participants treated with 250 mg of ceftriaxone intramuscularly increased from 8.7 percent in 2006 to 96.6 percent in 2014. The percentage of isolates with reduced cefixime susceptibility increased from 0.1 percent in 2006 to 1.4 percent in 2011, and then declined to 0.4 percent in 2013.

However, in 2014, the percentage of resistant isolates increased to 0.8 percent. While the numbers may appear tiny, they are scientifically significant.

The researchers say they cannot establish a causal relationship between treatment changes and improvement in susceptibility while the worsening 2014 data suggest any positive treatment trends may be fleeting. Based on the study results, they need to continue monitoring the situation while searching for new drugs.

Gonorrhea and You

The CDC recommends annual gonorrhea screening for all sexually active women younger than 25 and for older women with a new or non-monogamous sex partner. Inconsistent condom use is a major risk factor for the disease, especially among sex workers. Increased rates of gonorrhea have been documented in the past 20 years among MSM (men who have sex with men) in the U.S. and virtually all industrialized countries, as reported by the CDC. That said, gonorrhea is concentrated in specific geographic locations. Rates increased in the Northeast, South, and West during recent statistical years, while rates decreased in the Midwest, health officials note.

Source: Kirkcaldy RD, Hook EW, Soge OO, et al. Trends in Neisseria gonorrhoeae Susceptibility to Cephalosporins in the United States, 2006-2014. JAMA. 2015.