U.S. sees increase in syphilis and chlamydia rates: gonorrhea rate falls but resistance an issue.(News)

The rate of syphilis infection in the United States continues to rise, with an 8% increase in the number of reported cases in 2004, compared with 2003, the Centers for Disease Control and Prevention reported.

In 2004, the national incidence of reported primary and secondary syphilis cases was 2.7 100,000 persons (7,980 cases reported), up from 2.5/100,000 persons in 2003 (7,177 cases reported).

The increase has occurred entirely among men, particularly men who have sex with men, and may represent a return to promiscuous behaviors in that segment of the population as AIDS fears have fallen from the limelight, CDC officials said in a telephone news conference.

Among women, the syphilis rate remained stable between 2003 and 2004, at 0.8/100,000, but that plateau represents the first time in 10 years that there has not been a steady decline.

Regarding the other two reportable, non-HIV STDs, the rate of chlamydia infection rose, up 6% in 2004 from 2003, and the rate of gonorrhea fell 1.5%, but antibiotic resistance continued to grow. The increase in the chlamydia rate probably mostly reflects improved screening and better tests, the officials said.

The highest rates of chlamydia continued to be among adolescent females 15-19 years old, with a reported rate of 2,761/100,000 persons, and women 20-24 years old, with a rate of 2,630/100,000.

Efforts to increase chlamydia screening are a major priority for CDC, which recommends annual screening of sexually active women under age 25 years. A recent study conducted by the agency and Kaiser Permanente found that a program that prompted its primary care doctors to tie chlamydia testing to pap testing increased chlamydia screening among the plan's younger females by 30%, according to the CDC.