Comparison of human rotavirus disease in tropical and temperate settings.

Human rotaviruses (HRV) are a common cause of acute nonbacterial gastroenteritis in pediatric patients. A prospective study of HRV disease in a temperate (Dallas) and a tropical (San Jose, Costa Rica) setting demonstrated differences in seasonal distribution. In both locales, HRV accounted for 50% to 60% of acute nonbacterial gastroenteritis episodes from December through February; this period corresponded to the cooler months of winter in Dallas and to the dry season in San Jose. During the rest of the observation year, the virus was not recovered from any Dallas patients, but was found in 30% to 40% of Costa Rican patients in every month but May. Signs, symptoms, and laboratory values suggest the small bowel as the major site of pathophysiology; mucosal disruption may occur in some cases.