Interspecies transmission of agents must also be born in mind including a potential human involvement e since a number of live attenuated vaccines prepared in eggs are used in humans. A human gyrovirus (HGyV), which may be a contaminant from poultry origin rather than a virus of human origin, was reported nearly at the same time as the identification of AGV2 was published [19]. Subsequently,
other gyroviruses were identified in samples from
humans [20e22]. Thus, it is possible to speculate that perhaps one
or more of such viruses might have been introduced into humans
either by ingestion or handling of poultry and related products; yet
it may be possible that such introduction e if it indeed happened e
might have taken place by the administration of AGV2-
contaminated vaccines to humans. Clearly, though, such hypothesis
would require further investigation on additional vaccines,
particularly on modified live attenuated vaccines for human use
prepared in embryonated eggs.