Infectivity of GI and GII noroviruses established from oyster related outbreaks

► From five oyster related outbreaks data, infectivity of Norovirus was evaluated. ► Bayesian analysis was done conditionally from the ingested dose (genome copies). ► Infectivity for secretor positive (Se+) and negative (Se−) individuals is different. ► Difference of infectivity between genogroups (GI and GII) is not detected. ► High infectivity estimates was confirmed for NoV GI and GII in Se+ individuals.