SIOUX FALLS, S.D. (AP) — Health officials say Internet hookups by anonymous partners are driving a distressing increase in sexually transmitted disease in South Dakota.

Cases of syphilis, gonorrhea and chlamydia all are ahead of last year's pace. Officials attribute the increase to online liaisons and to an increasingly lax attitude about risky behavior.

State Epidemiologist Lon Kightlinger tells the Argus Leader the trend has made it hard to track and control STDs. He says if someone who's infected comes to a clinic for help, the partner often is gone from the scene without either knowing the other's name.

City of Sioux Falls disease intervention specialist Judy Kendall says that although STDs by law must be reported to the state, the numbers probably are a fraction of the true total.

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