BISMARCK, N.D. (AP) — State health officials in the Dakotas are trying to address what they say is an outbreak of syphilis.

There have been 33 reports of the sexually transmitted disease in North Dakota this year, up from 26 at the same time last year and just 14 the year before. In South Dakota there were 43 cases in the first four months of the year, compared with 49 cases for all of 2013.

North Dakota's Health Department says a lot of the cases are on the Standing Rock Sioux Reservation, which straddles the two states.

Health officials have attributed the increase in cases to a variety of factors, including drug use and people not practicing safe sex.

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