WEDNESDAY, Feb. 8 (HealthDay News) -- Antibiotic-resistant gonorrhea is an increasingly worrisome reality, and steps need to be taken to limit the risk that an untreatable strain of the sexually transmitted disease will spread, U.S. researchers warn.

"We're trying to stay a step ahead by putting these warnings and alerts out," said Dr. Gail Bolan, of the U.S. Centers for Disease Control and Prevention's division of sexually transmitted diseases prevention.

Over 600,000 Americans contract gonorrhea every year, making it the nation's second-most common communicable disease. Minorities of all types -- whether in terms of race, ethnicity or sexual orientation -- are considered among the most vulnerable populations, according to background information in the new report.

Drug-resistant gonorrhea isn't a new phenomenon, Bolan and her colleagues said. During World War II, gonorrhea became resistant to the drug sulfanilamide. In the 1980s, resistance to the antibiotics penicillin and tetracycline appeared. More recently, fluoroquinolone resistance was observed in 2007.

The problem today, however, is that so-called third-generation cephalosporins (including orally administered cefixime and the injectable ceftriaxone) are the only remaining types of effective antibiotics recommended by the CDC, when taken alongside one of two other oral antibiotics (either azithromycin or doxycycline).

Writing in the Feb. 9 issue of the New England Journal of Medicine, the researchers warned that signs of resistance to even this line of defense have been observed.

"The point now," Bolan said, "is that we are down to the last class of antibiotics that we know -- that have been studied -- to be effective in the treatment of gonorrhea." If a strain of resistant gonorrhea were to take hold, "we have the potential of having no other antibiotics to turn to," she added.

Cephalosporin-resistant strains of the disease have been identified in Japan (2003 and 2009) and the United Kingdom (2010). Such drugs remain "highly effective" against most strains of gonorrhea seen in the United States, the study authors noted.

Still, the investigators said that patient vigilance and coordinated public health policies are needed if the United States is to stay a step ahead of cephalosporin-resistant strains.

Prevention is always key, Bolan said, noting that gonorrhea is preventable with the use of condoms.

But given that gonorrhea is often symptomless, "many patients who have this infection don't know they are infected. So for individuals, it's very important to go in for routine medicals," she added.

"And certainly if you've got symptoms, we're concerned that you . . . get evaluated quickly," she added. For women, symptoms can include vaginal discharge, a burning sensation during urination and pain during intercourse. For men, telltale signs include a clear penile discharge, burning on urination and pain during defection.

While screening methods are effective, they don't indicate resistance to antibiotics. So, Bolan said, patients and doctors have to work together to ensure that the recommended antibiotic treatment is doing the job, while monitoring for any sign of treatment failure.

The sexual partners (going back two months) of those diagnosed should also be treated. And because gonorrhea can be a potential sign of HIV infection, the researchers urge repeated HIV testing for those diagnosed with gonorrhea.

Commenting on the study, Dr. Thomas Quinn said that the specter of rising antibiotic-resistant gonorrhea is worrisome.

"It's a very common disease that is in the millions of cases if we're talking globally," said Quinn, senior investigator in the International HIV/STD section at the U.S. National Institute of Allergy and Infectious Diseases.

"If untreated or unsuccessfully treated, it usually is not life-threatening, but it does have severe complications in both sexes," he added. It's particularly dangerous for women "because of the risk for infertility."

According to the CDC, each year roughly 24,000 American women become infertile due to an untreated sexually transmitted infection.

"For men there can be extremely painful complications involving the scrotum, although not fertility," said Quinn, who is also a professor of medicine at the Johns Hopkins School of Medicine in Baltimore.

"So this is a harbinger of bad times ahead unless we really take the proper steps to address it," he added. "We have a very common transmitted organism that is once again rearing its head by increasing frequency in the population and increasing resistance. And the public needs to know about this."

More information

For more on gonorrhea, visit the U.S. Centers for Disease Control and Prevention.

SOURCES: Gail A. Bolan, M.D., division of STD prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, U.S. Centers for Disease Control and Prevention, Atlanta; Thomas C. Quinn, M.D., M.Sc., senior investigator, infectious diseases, and International HIV/STD section, U.S. National Institute of Allergy and Infectious Diseases, and professor of medicine, Johns Hopkins School of Medicine, Baltimore; Feb. 9, 2012, New England Journal of Medicine

Copyright © 2012 HealthDay. All rights reserved.