After an encouraging drop in 2009, the number of sexually transmitted diseases in Minnesota climbed to a record last year, with the number of new syphilis infections almost doubling and chlamydia cases hitting an all-time high.
Overall, the state recorded 17,760 cases of sexually transmitted disease (STD), up 5 percent from 2009, the Minnesota Department of Health said in an annual report released Wednesday.
State health officials couldn't pinpoint a cause, but expressed alarm -- particularly at the increase in chlamydia, an infection that produces few physical symptoms but can eventually result in infertility and premature births.
While an increase in unprotected sex might explain the rising numbers, it's equally possible that an increase in screening is finding more previously hidden cases, said Peter Carr, who directs the health department's STD surveillance section. Screening has increased steadily over the past decade. "The more aggressively populations are screened," Carr said, "the more cases you'll find."
Chlamydia was, by far, the most common infection, with 15,294 cases last year. Gonorrhea was second (2,119) and syphilis was third (347).
Mathematical models suggest continued screening will eventually reduce the number of infections, because it will identify infected people before they can spread the diseases, Carr said.
Prevention advocates nevertheless worried about future infection tallies, especially if state or federal budget cuts weaken or eliminate family planning or disease-prevention programs.
While chlamydia rates are increasing in the suburbs, rural areas and even among nontraditional populations such as men over 50, they continue to be highest among young adults, blacks and high-poverty communities such as Minneapolis.