A state health report shows Iowa’s syphilis rate continues to climb, with 877 cases of that sexually-transmitted infection last year. It marks the fourth straight year cases have risen, mirroring a national trend. State Medical Director Robert Kruse says the reason for the increase is unclear, but he says syphilis usually begins with a painless blister that goes away on its own, so it can be harder to detect in earlier stages.

Iowa’s rates of chlamydia and gonorrhea dropped last year. Kruse says doctors have seen syphilis cases increase for women, which led to a rise in congenital syphilis — where a woman passes the illness to her child during pregnancy. He says doctors should consider additional screenings for their pregnant patients who are at risk.

Kruse says it’s important that Iowans recognize signs and symptoms of S-T-Is and go in for testing if they think they may have been exposed.