An Enterovirus Outbreak Associated with Probable Rhombencephalitis in a Nursery, Tak Province, Thailand, 2017

Abstract

On 4 Sep 2017, the Bureau of Epidemiology received a notification from Tak Provincial Health Office on an outbreak of hand, foot and mouth disease (HFMD) at a nursery following one death at the provincial hospital. An investigation was carried out to confirm the diagnosis and identify source of infection. Active case finding was performed in the nursery, index case’s house and community. Medical records were reviewed, and children, teachers and household members of the index case were interviewed. Confirmed cases were defined as children or teachers in the nursery, household members and neighbors of the index case who was found to have enterovirus from fresh stool or nasopharyngeal/throat swab by polymerase chain reaction. Total 30 cases were identified, including nine confirmed, one probable (index case) and 20 suspected cases. The overall attack rate was 51.7% and case fatality proportion was 3.3%. There were 26% of enterovirus 71, 13% of coxsackie B4 identified from fresh stool samples of symptomatic cases. Neither samples from asymptomatic close contact or nasopharyngeal/throat swab was positive. No residual chlorine in the supplied water at the nursery was detected. We recommended hand washing with soap, wash the toys more than once a week, chlorinate the water to more than 0.5 ppm and increase awareness of enterovirus infection to early detect the outbreak.
 
Keywords: Hand, foot and mouth disease, enterovirus, rhombencephalitis, nursery