OKLAHOMA CITY (AP) - Infectious diseases that used to be unknown in Oklahoma are becoming more prevalent.
The Oklahoma Department of Health says the state has already recorded its first case of West Nile virus this year, a disease that sickened 84 people last year and killed eight.
The first case of the chikungunya virus was recorded in the state this year, and a Delaware County man who was the first Oklahoma victim of the Heartland virus was the second person in the nation to die from the disease.
Dr. Kristy Bradley, the state's epidemiologist, says changes in climate, the urbanization of previously forested areas of the world and travel are principle reasons the diseases are appearing in Oklahoma.
Bradley says there are no vaccines for the diseases and that prevention is the key.
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