21.   Alarmists have weighed in with dire predictions of how a warming of tropical and subtropical regions will aggravate the scourge of tropical diseases.

22.   After tropical diseases forced his return to the United States, he took a job preparing maps of the Titusville, Pa., area.

23.   By the time Malaysia catches up to where Singapore is now, many tropical diseases may have been tamed.

24.   Cooled by trade winds, they provided safe haven and a healthier climate at a time when malaria and other tropical diseases were spreading on the mainland.

25.   Dense with text, their ads often evince all the charm of a treatise on some rare tropical disease.

26.   Drug companies and some analysts argue further that if developing countries honor patents, drug companies will have more incentive to develop treatments for tropical diseases.

27.   During the war, he was part of a U.S. team doing research in laboratories and in the field to combat tropical diseases, especially malaria.

28.   Farrar may have actually been afflicted by a tropical disease he picked up during a trip to South America.

29.   For example, if tropical diseases migrate into more industrialized nations, which is likely as temperatures rise, pharmaceutical companies may see their markets expand.

30.   He never had to recover from a bullet wound or battle a rare tropical disease.