Neonatal Enterovirus Infection: Virology, Serology, and Effects of Intravenous Immune Globulin

Abstract
A prospective study of the virology of and serological responses to enterovirus infection in 16 neonates (3 50% tissue culture infective dose per mL (TCID50) and 6.8 × 101 TCID50/mL, respectively. Viremia was associated with onset of illness in the first 5 days of life, low initial serum neutralization titer, and the presence of echovirus serotypes. Randomized administration of intravenous immune globulin (IVIG; 750 mg/kg) to nine neonates overall modestly increased serum neutralization titers but did not reduce the daily incidence of viremia and viruria compared with that of controls. However, receipt of IVIG containing a neutralization titer of ⩾ 1:800 to the patients' own viral isolates was associated with significantly higher serum neutralization titers and more rapid cessation of viremia and viruria. Future trials of IVIG for neonatal enterovirus disease should assess the efficacy and safety of higher or repeated doses of this agent and/or of IVIG lots selected for their high titers to frequently circulating and/or particularly virulent enterovirus serotypes.