It looks like it's time to start the safe sex campaigns again. Why? Because according to officials at the Centers of Disease Control and Prevention, one million new cases of chlamydia were report. That's the most for the unknown sexually transmitted disease.

Officials also announced that chlamydia is not the only STD on the rise. Gonorrhea rates are rising, fueled by a version resistant to antibiotics. Syphilis also rose for the first time in 15 years.

"Hopefully we will not see this turn into a trend," said Dr. Khalil Ghanem, an infectious diseases specialist at Johns Hopkins University's School of medicine.

The CDC releases a report each year on chlamydia, gonorrhea and syphilis, three diseases caused by sexually transmitted bacteria.

Chlamydia is the most common. Nearly 1,031,000 cases were reported last year, up from 976,000 the year before.

The count broke the single-year record for reported cases of a sexually transmitted disease, which was 1,013,436 cases of gonorrhea, set in 1978.

Putting those numbers into rates, there were about 348 cases of chlamydia per 100,000 people in 2006, up 5.6 percent from the 329 per 100,000 rate in 2005.

Since 1993, the CDC has recommended annual screening in sexually active women ages 15 to 25. Meanwhile, urine and swab tests for the bacteria are getting better and are used more often, for men as well as women, said Dr. John M. Douglas Jr., director of the CDC's Division of Sexually Transmitted Disease Prevention.

About three-quarters of women infected with chlamydia have no symptoms. Left untreated, the infection can spread and ultimately can lead to infertility. It's easily treated if caught early.