Prevalence of rotavirus and its relation with climatic factors in Cumana, Venezuela

During the period June 1993 to June 1995, 377 fecal samples from hospitalized young children with extreme diarrhea in the Antonio Patricio de Alcala Hospital in Cumana, Venezuela were taken, as well as similar samples from 89 asymptomatic children of the same age range. Viral ARN was extracted from the samples with phenol-chloroform, ethanol precipitation, gel electrophoresis of poly-acrylamide (Page) and silver tincture. Rotavirus was found in 116 (38.77%) of the diarrhea samples and in 7 (7.87%) of the non-diarrhea samples. Only in 105 of the diarrhea samples was it possible to detect electro-ferrotype patterns, in which 84 (80%) were the long electro-ferrotype; 19 (18.09%) were short electro-ferrotype; and two (1.91%), had mixed electro-ferrotypes. In the non-diarrhea 5 (71.43%) were the long type, and 2 (28.57%) were short. Using co-electrophoresis, 7 electro-ferrotype patterns were distinguished: four long, two short, and one electro-ferrotype mixture. A significant inverse correlation was found between the monthly prevalence of rotavirus and the mean temperature (r=-0.5583, p< 0.05) and a significant inverse relationship between the monthly prevalence of rotavirus and average monthly precipitation.