SEROLOGICAL RESPONSE TO ROTAVIRUS INFECTION IN NEWBORN-INFANTS

We report the identification of rotavirus in stools of newborn infants at the ''Hospital Materno Infantil de Caricuao'' (HMIC) as well as th e infants' serological responses to various rotavirus strains. The ser ological responses of another group of rotavirus-positive neonates stu died previously at the ''Maternidad Concepcion Palacios'' (MCP) hospit al was also evaluated. Fifty-four of 266 (20%) newborns examined at HM IC shed rotavirus. The infection rate was higher among infants admitte d to the nursery (75%) than in those ''rooming in'' with their mothers (7%) (P<.01). Eleven of the 54 neonates (20%) had diarrhea; seven of them experienced mild, short-lived episodes, whereas five had frequent diarrhea bouts or diarrhea lasting for over 3 days; the remaining 43 infants were asymptomatic. Twenty-seven of 28 rotavirus specimens test ed at HMIC had VP7 serotype 4 specificity and one belonged to VP7 sero type 1; VP4 typing performed on 24 of the viruses by RNA hybridization showed these viruses to be similar to the M37 strain, a rotavirus pre viously associated with asymptomatic infections in newborns at MCP. Ig A seroresponses were detected in eight of 11 infants born at HMIC (73% ), but most failed to developed neutralization responses to homologous or heterologous strains. Newborn infants who had shed the M37 rotavir us strain at MCP reacted similarly: 16 of 24 (67%) developed a rotavir us IgA rise, but only 29% developed a neutralization response,