SPOKANE — Health officials in northern Idaho and eastern Washington say the sexually transmitted disease gonorrhea is at outbreak levels.

Spokane health officials announced Thursday that identified cases of gonorrhea grew more than 50 percent over the past three months. The northernmost five counties in Idaho saw cases jump 300 percent in 2013, and officials expect more cases to be reported this year.

“We are seeing the highest rate we’ve seen in the last 20 years,” Anna Halloran, Spokane Regional Health District disease intervention specialist, told The Spokesman-Review.

Spokane County ranks sixth among Washington’s counties for the number of gonorrhea cases per 100,000 people and fourth for chlamydia, based on state health department records. The number of gonorrhea cases increased from 181 in 2012 to 329 in 2013 and continue to climb this year, according to the Spokane Regional Health District.

Idaho’s Panhandle Health District, which includes Benewah, Bonner, Boundary, Kootenai and Shoshone counties, recorded 15 gonorrhea cases in 2012 and 42 in 2013.

“Our numbers are relatively low, but the numbers are telling us we have a gonorrhea endemic,” said Jeff Lee, a district epidemiologist. “We are interviewing people about where they meet people, and we are not finding a common ground. In 2007, it was bars, and we put up fliers and handed out condoms.”

Gonorrhea often doesn’t have symptoms, so officials suggest that women who are under the age of 25 and who are sexually active get tested, Halloran said. She also recommended that people who might be considered at an increased risk of infection, such as someone who has multiple sex partners or men who have sex with men, get tested.

If left untreated, gonorrhea can cause infertility, pelvic pain or tubal pregnancy in women.

Gonorrhea and chlamydia are the most common sexually transmitted diseases in the Inland Northwest as well as nationwide; women between the ages of 15 to 24 are the most at risk, according to the U.S. Centers for Disease Control and Prevention.

While chlamydia has increased slightly in Spokane with more than 2,000 cases reported last year, officials say the numbers haven’t reached any special alert status. The symptoms may include swelling and pain of internal sexual organs for men, but it often has no symptoms in women, Halloran said.

“Not having sex would be the best way to protect yourself,” Halloran said. Wearing a condom or being mutually monogamous also work.

“There are still good antibiotics to treat both diseases, and partner treatment is also available (in Spokane County),” Halloran said. “We call them to let them know they were exposed without telling them which partner they got it from. Hearing things from the health department seems to help them take the call seriously.”