SAN DIEGO -- Highly drug-resistant gonorrhea has been spreading rapidly across the United States, with particularly high rates appearing in Long Beach, Orange County and San Diego, it was reported Friday.

The drug-resistant gonorrhea accounts for 13 percent of all cases of the sexually transmitted disease, according to federal researchers quoted by the Los Angeles Times.

In a survey of 26 areas around the country, the Centers for Disease Control and Prevention found particularly high rates of drug-resistance in Long Beach, Orange County, San Diego, San Francisco, Philadelphia and Honolulu, The Times reported. Drug-resistant infections accounted for at least 25 percent of all cases in those areas.

"That's a really dramatic trajectory in terms of emerging resistance," Dr. John M. Douglas Jr., director of the CDC's Division of Sexually Transmitted Disease Prevention, said in remarks reported by The Times.

The CDC Thursday urged doctors to stop using a powerful class of antibiotics -- fluoroquinolones -- against the disease. It now recommends a single class of antibiotics known as cephalosporins, The Times reported.

Gonorrhea, which is caused by a bacterium, is the second most commonly reported infectious disease in the nation after chlamydia. There are an estimated 700,000 new cases each year.

Gonorrhea can lead to severe complications in women, including infertility, and increases the risk of contracting other sexually transmitted diseases, including HIV.