U.S. citizens are safe from the reported gonorrhea superbug -- for now. But the U.S. Centers for Disease Control and Prevention confirms that gonorrhea is evolving as increasingly resistant to available antibiotics for treatment.

No cases of the resistant gonorrhea have been found in the U.S., officials say. But the CDC says its laboratory studies are confirming that gonorrhea is showing signs of resistance to the antibiotic drugs used to treat it.

If untreated, or if treatment is not successful the sexually transmitted disease has complications including pelvic inflammatory disease, arthritis, chronic pelvic pain, fertility problems in women, and meningitis (inflammation of the brain),

Resistant, or superbug strains of gonorrhea have shown up in Norway and Japan. In Norway, heterosexual men have been identified as having the superbug strain that doesn't respond to antibiotics, and a female sex trade worker was identified with it in Japan. The findings were reported this week at the International Society for Sexually Transmitted Disease Research conference ongoing in Quebec.

The newly identified gonorrhea strain that doesn't respond to antibiotics is perhaps a true superbug that initiates a future era of untreatable gonorrhea, wrote the team of Japanese and Swedish scientists reporting on the issue.

Gonorrhea is one of the most common diseases worldwide passed from one person to another during sexual activity. In the U.S. the overall rate of gonorrhea has decreased in recent years to the lowest recorded rate ever, but it remains the second most commonly reported notifiable sexually transmitted disease in America.

According to the CDC, 700,000 new gonorrhea infections occur each year -- and until recently there's been no concern regarding treatment since so far infections are cured in the U.S. at a rate of 95 percent to 99 percent with antibiotics treatment.

This isn't the first time a gonorrhea superbug concern has emerged. The current antibiotic used is the fourth health officials have treated gonorrhea with since the 1940s. A few years ago gonorrhea first became resistant to antibiotics used in Asia, before the strain arrived in the United States, but a new drug was found that addressed the problem and treatment of gonorrhea remained at a high success rate.

But the current drugs used to treat gonorrhea are the last line of defense until a new drug is developed. That's why health officials are closely watching to see if the new gonorrhea superbug becomes a global problem before that occurs.

Gonorrhea is caused by the Neisseria gonorrhoeae bacteria. People transmit the bacteria from one person to another through sexual activity, including intercourse, oral, or anal sex. Statistics show men have a 20 percent chance of infection after sex activity with a woman who is infected with gonorrhea, while women have a 50 percent chance of having sex with a man infected with gonorrhea.

Also, an infected mother can transmit gonorrhea to a newborn child during vaginal childbirth -- a potential problem is the superbug strain continues to emerge since treatment may not be available.

Initial symptoms and signs for gonorrhea infection include in men a burning sensation while urinating, or a white, yellow or green discharge from the penis. In women, symptoms or gonorrhea may be mild, and sometimes undetectable. Other times, symptoms include a burning sensation while urinating, and increased vaginal discharge.