CNS MANIFESTATIONS OF INFECTIONS WITH NPEV Meningitis

W an estimated incidence in highincome countries of 12–19 cases per 100,000 population per year, viral meningitis is almost 3-fold more frequent than bacterial meningitis. Non-polio enteroviruses (NPEV) are the main cause of viral meningitis worldwide, and young age is an important epidemiological risk factor. Although the acute phase is often mild, NPEV infections can cause severe central nervous system (CNS) disease and result in fatal outcome. Transmission of enteroviruses (EVs) occurs mainly via the fecal-oral route and to a lesser extent by respiratory droplets. Therefore, enhancing hand hygiene can diminish viral spread. Although the peak seasonality occurs in summer and fall in temperate climates, enteroviral infections occur perennially in tropical and subtropical areas. Improved molecular typing and several EV surveillance programs (primarily geared toward the detection of poliovirus outbreaks) have led to higher detection rates of enteroviral infections worldwide. Currently, there are more than 100 serotypes of NPEV identified that are subdivided into 4 species (A to D). Since the 1970s, there have been a number of reports of NPEV outbreaks with human EV 71 (EV71) with sometimes fatal outcomes especially in eastern Europe and the Asia-Pacific region. The World Health Organization reports more than 2000 deaths of an estimated 6 million infections. There are large differences in the case fatality rate between the different outbreaks, which might be related to differences in the pathogenic effect on the CNS of different genogroups of EV71. In this review, typical CNS manifestations of EVs and recent outbreaks in children are summarized, and diagnostic tools and possible treatment and prevention strategies are presented.