The Epidemiologic Characteristics and Infection Control Measures for an Outbreak of Rotavirus Infection in the Neonatal Unit

Abstract

BACKGROUND The purpose of the study is to investigate an outbreak of rotavirus infection in a neonatal unit and to study the effectiveness of the infection control measures implemented. MATERIALS AND METHODS We investigated an outbreak of rotavirus infection in a neonatal unit equipped with 4 newborn nursery rooms (NNRs) from Dec. 2002 through May 2003. After performing initial surveillance study in all 11 newborns and 21 staffs for stool rotavirus shedding, we observed the course of the outbreak by assessing week incidence and introducing reinforced control measures. P (VP4) genotypes of rotavirus isolates were determined to investigate the link between NNRs and the pediatric ward. RESULTS Initial surveillance showed that 2 newborns from NNRs were infected, but none of staffs were infected. Despite initial intervention (70% alcohol based gel for hand hygiene, cohorting of the neonates, and education for staffs), new cases increased up to 9.2 cases per 100 neonate week. Even after further control measures such as using commercialized milk and recruiting new staffs, cases continued to occur with 22.2 cases per 100 neonate week. Finally, a temporary NNR was set up and disinfection of surfaces and equipments from the neonatal unit was performed, after which the outbreak ceased. All rotaviruses isolated during the outbreak from newborns in NNRs were genotype P2A, whereas isolates from the pediatric ward were genotype P1A, P1B, and P3. CONCLUSIONS This study indicates that rotaviral diarrhea is highly transmissible and when outbreak occurs in the neonatal unit, excessive control measures such as the ward closure may be needed.