A Study of the Local versus Country Level Spatiotemporal Distribution of Enterovirus 71

Abstract

Human Enterovirus 71, which causes Hand, Foot and Mouth Disease (HFMD), is a clinically challenging pathogen because of the central nervous system complications that it can cause in young children. At times these complications can lead to long-term attention deficit or hyperactivity cognitive problems or even death in severe cases (Chan, Sam, Wee, Abubakar, 2011). There is currently an EV71 vaccine in the works. It is therefore valuable to more fully understand the mode and kinetics of transmission of this pathogen to more effectively implement a public health vaccination strategy by focusing on the spatial heterogeneities in transmission on both the local level in Sarawak, Malaysia, and the country level in Japan. Therefore, in preparation of this thesis I studied the transmission of this pathogen in Sarawak, Malaysia and Japan in recent outbreaks. The data collected from Sarawak contained qualitative information from the first 79 cases of the 2009 outbreak, including the address, age, gender and ethnicity of the infected individuals. The data from Japan contains the number of cases, divided into the 47 different prefectures, from the years 1983-2011 (excluding 1998), allowing for country level spatial analysis of the virus. These data did not show any distinct relationship between incidence levels and population levels or density. However, it is possible that the lack of information on asymptomatic cases may explain some of discrepancies in these findings.