Interference between enteric viruses and live-attenuated rotavirus vaccine virus in a healthy Australian birth cohort.

Rotavirus vaccines have reduced effectiveness in high mortality settings. Interference between enteric viruses and live-attenuated oral vaccine strains may be a factor. In a birth cohort of healthy Australian infants, parents collected weekly stool samples. Three-hundred and eighty-one paired swabs collected within 10-days of RotaTeq (Merck, Pennsylvania, USA.) vaccination from 140 infants were tested for 10 enteric viruses and RotaTeq strains. Collectively, both RNA and DNA viruses were negatively associated with RotaTeq shedding (adjusted odds ratio 0.29 [95% confidence interval [0.14─0.58]) and 0.30 [0.11─0.78], respectively). Enteric viruses may interfere with RotaTeq replication in the gut and thus RotaTeq stool shedding.