GENOME ANALYSIS OF SOUTH-AMERICAN ADENOVIRUS STRAINS OF SEROTYPE-7 COLLECTED OVER A 7-YEAR PERIOD

DNA restriction analysis was carried out on a sample of 212 epidemiolo gically unrelated adenovirus (Ad) strains of serotype 7 isolated in Ch ile, Uruguay, and Argentina from nasopharyngeal aspirates of children with acute lower respiratory disease between 1984 and 1990. The identi fied genome types were Ad7b (n = 12), Ad7c (n = 21), and Ad7h (n = 179 ). The analysis of the occurrence of the three genome types throughout the study period revealed that Ad7c was the predominant virulent vari ant in 1984 and indicated that a shift to genome type 7h took place in 1986. Ad7b cocirculated with the other genomic variants at a relative ly low frequence.