Serum and Coproantibody Responses to Rotavirus Infection in Children during the First Two Years of Life

The serum and coproantibody response (IgG and IgA) to naturally acquired rotavirus infections and reinfections in the first two years of life were studied in 13 cases and 12 control children using enzyme — immunoassay. A 100% IgG seroconversion and coproconversion occurred after tertiary and quaternary infections respectively. Unlike the IgA coproantibody response, serum IgG was detected more frequently after symptomatic (89%) than asymptomatic (50%) infections, and its duration and titre were boosted by reinfections. The durations of both responses was prolonged when reinfection occurred at 15 months versus 8 months. Both responses were observed after primary infection in the first two months of life. Higher instances of virus reinfections were detected serologically (72.5%) than virologically (27%). The results suggest that at least 3 doses of a rotavirus vaccine will be required before 4 months plus boosters around the 10th and 15th months. Further, during vaccine trials, virus infections should be monitored virologically and serologically.