Viral Infections of Central Nervous System in Children

Central Nervous System (CNS) infections are caused by a variety of pathogens including bacteria, virus, fungi, protozoa, and parasites. Viral CNS infections can present as meningitis, encephalitis, or localized abscesses. Such infections are challenging to diagnose and the blood brain barrier in the human body guards the entry of the pathogens into CNS. The CNS is also shielded by neuroanatomical barriers which may be blood CSF barrier or the blood brain barrier and the fibroblasts from olfactory nerve. Our immune cells enhance these barriers by activating T cells with protective function. Once invasion occurs, the viruses interact with various cell populations of CNS and can induce pro-inflammatory immune response that leads to development of pathologies like viral meningitis and encephalitis. Children have immature immune defenses and blood–brain barrier; hence, they are more vulnerable to viral CNS infections compared to adults. Viruses like enteroviruses account for more than 50% of CNS infections amongst children. Infections, either mild or severe, severely impact the quality of life in developing children and chief cause of morbidities and mortality worldwide. This chapter aims to provide an overview on viral pathogens of nervous system, their pathogenesis, diagnosis, and treatment options available in the current scenario. The authors review various viral pathogens of CNS in children and describe their casual microbiological cause, clinical features, and provide an update on the classical and latest diagnostic approaches and treatment strategies available for them. Newly developed PCR-based methods that are efficiently capable of detecting and diagnosing the neurotropic viruses in almost all sample types are discussed. The chapter finds its importance in providing an overview for management approach of viral infections of the central nervous system in children from the point of clinical presentation, diagnosis, treatment, and complications.