Inter-relationships among subgroups, serotypes, and electropherotypes of rotaviruses isolated from humans.

In an epidemiological study of human rotavirus (HRV) infections in metro Jeddah, Saudi Arabia, the relationships among subgroups, serotypes, and RNA electropherotypes of the rotavirus isolates were investigated. Of the 523 rotavirus-positive stool specimens, 245 were examined for subgroup, serotype, and electropherotype. Of these, 84 isolates were analyzed for their subgroup and RNA electropherotype specificites, 12 (14.3%) were of subgroup 1, 69 (82.1%) were of subgroup II, and 3 (3.6%) were a mixture of subgroup I and II. Of the subgroup 1 specimens, 5 (41.7%) showed long electrophoretic migration patterns and 7 (58.3%) showed short patterns. In subgroup II specimens, 66 (95.7%) were of long patterns and 3 (4.3%) of short patterns. The relationship between HRVS serotypes and electropherotypes was also determined for the same 245 rotavirus specimens. Of these, 36 (14.7%) exhibited short RNA patterns and 209 (85.3%) exhibited long patterns. The short pattern specimens consisted of serotype 1 (8.3%), serotype 2 (63.9%), serotype 3 and serotype 4 (2.8%) each. The long pattern specimens consisted of serotype 1 (60.3%), serotype 2 (1.4%), serotype 3 (7.2%) and serotype 4 (17.7%). Among the previous 245 specimens, subgroup specificities were available for 51 specimens. All subgroup I were of serotype 2, and all subgroup II were of serotype 1, 3 or 4. RNAs of either subgroup showed both long and short electropherotypes. No relationship could be established between subgroups or serotypes and a particular electropherotype. It seems unlikely that electropherotyping of human rotavirus (HRV) can be used for identifying the subgroups or serotypes of strains.