SEROTYPES AND ELECTROPHEROTYPES OF HUMAN ROTAVIRUS DETECTED IN THE CITY OF SAO-LUIS (MA), BRAZIL

A total of 22 (65%) of 34 representative rotavirus-positive specimens from infants with acute gastroenteritis were electropherotyped (RNA ge nome segments) and serotyped using an enzyme immunoassay with monoclon al antibodies (ELISA with MAbs). Serotype 3 was predominant during the 10-month study period (41%), followed by serotype 1 (27%) and serotyp e 4 (9%). Serotype 2 was not found. Rotavirus strains were grouped int o 3 major electropherotypes designated V, W and Z, each corresponding to a single serotype, i.e., serotypes 1, 3 and 4, respectively. Three strains that could not be typed by the serologic technique showed the W electrophoretic profile. The relative migration of the gene segments 7-9 was the main feature distinguishing the predominant serotype 3 fr om the other serotypes. The migration of segments 2 and 5 was also imp ortant for differentiating serotype 4 strains. The present study stren gthens the view that electropherotyping, when used in conjunction with serotyping, can help characterize atypical and unusual strains, as we ll as rotaviruses that cannot be typed by the serologic technique.