1.   Almost from the start of the epidemic, many suspected that sexually spread diseases played a role in AIDS.

2.   Smith said that the Centers for Disease Control and Prevention uses the data to help design and target public health campaigns to control sexually spread diseases.

3.   Smith said the Centers for Disease Control and Prevention use the data to help design and target public health campaigns to control sexually spread diseases.

4.   The miners destroyed forest, polluted rivers and spread diseases fatal to Indians.

5.   They crowd out native plants and animals, spread disease, damage crops and threaten drinking water supplies.