SIOUX FALLS, S.D. (AP) — South Dakota Department of Health officials say the number of syphilis cases reported last year was the most in 44 years.

An annual summary of infectious diseases in the state shows that 48 syphilis cases were reported in 2013.

The most reports of the sexually transmitted disease were in the Sioux Falls area, the largest population area in the state, with 23 cases, and Corson County, where the Standing Rock Reservation is located. Standing Rock reported 14 cases.

The Argus Leader reports that the Sioux Falls cases involve mostly men, and the Corson County cases both men and women.

The Standing Rock Reservation straddles North and South Dakota.

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