[Study of Coxsackie A 10 virus infection in newborn and suckling mice of the strains A2G, ICR-K and CBA].

Differences in the susceptibility to paralytogenic infection with Coxsackie A10 virus were found in neonate and suckling mice belonging to A2G, ICR-K and CBA strains and ICR-K/CBA and CBA/ICR-K hybrids in the F1 generation. At the first passage in vivo the more susceptible strains selected paralytogenic viral particles from among the cytopathogenic and non-pathogenic Coxsackie A10 virus populations. The differences in susceptibility could not be related either with the humoral immune response to virus or to the rate of fixation of virus on the neonate mouse muscle cell receptors.

Influenza hemagglutination-inhibiting antibodies in hospitalized children. Distribution of specific activity into IgM, IgG and IgA classes.

Sera from 75 children hospitalized with a clinical diagnosis of acute respiratory virus disease were tested by hemagglutination-inhibition as regards influenza A2 and B antibody shifts. In 48 patients there was an antibody shift during the clinical evolution of the disease (against influenza A2 in 34, B-- in 11, A2 and B in 3cases). A significant proportion of sera with antibody shift associated with a decrease of serum IgG levels and with an increase of serum IgM and IgA levels.