The rationale for integrated childhood meningoencephalitis surveillance: a case study from Cambodia

PROBLEM: Recent progress in vaccine availability and affordability has raised prospects for reducing death and disability from neurological infections in children. In many Asian countries, however, the epidemiology and public health burden of neurological diseases such as Japanese encephalitis and bacterial meningitis are poorly understood. APPROACH: A sentinel surveillance system for Japanese encephalitis was developed and embedded within the routine meningoencephalitis syndromic surveillance system in Cambodia in 2006. The sentinel surveillance system was designed so surveillance and laboratory testing for other etiologies of neurological infection could be incorporated. LOCAL SETTING: The Communicable Disease Control department of the Ministry of Health in Cambodia worked with partners to establish the sentinel surveillance system. RELEVANT CHANGES: The sentinel surveillance system has provided important information on the disease burden of Japanese encephalitis in Cambodia and is now providing a platform for expansion to incorporate laboratory testing for other vaccine-preventable neurological infections in children. LESSONS LEARNED: Sentinel surveillance systems, when linked to syndromic reporting systems, can characterize the epidemiology of meningoencephalitis and identify the proportion of hospital-based neurological infection in children that is vaccine preventable. Integrated systems enable consistency in data collection, analysis and information dissemination, and they enhance the capacity of public health managers to provide more credible and integrated information to policy-makers. This will assist decision-making about the potential role of immunization in reducing the incidence of childhood neurological infections.