Overall the results suggest that HMOAstV-C is a common infectious agent circulating in human populations. It is also possible that the studies described here underestimate the true seroprevalence of HMOAstV-C that may result from transient antibody titers from older infections and the genetic diversity of this newly recognized agent. The higher prevalence of antibodies in adults (65%) suggests that most adults are seropositive; however, it is unknown whether the presence of antibody is protective against infection. Nevertheless, compared to children, adults show a markedly higher incidence of HMOAstV-C infection. Further- more, the detection of high prevalence of antibodies in the 0-6 month old children is consistent with the presence of maternal antibodies. In infants, waning maternal antibodies for many infectious agents is often observed [30,31]. Additional investigation including prospective analysis of antibody responses by LIPS from acute infection would be worthwhile. 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