Viral meningoencephalitis: A review on etiological spectrum & advances in laboratory diagnosis
DOI:
https://doi.org/10.63719/imrj.2026.01(SE).05Keywords:
Viral meningoencephalitis, herpes simplex virus (HSV), enterovirus, viral PCR, next-generation sequencing (NGS)Abstract
Viral meningoencephalitis remains a critical global health priority, representing a significant burden of neurological disease and mortality worldwide. Characterised by acute inflammation of the meninges and brain parenchyma, this disease demands rapid diagnostic precision to guide clinical intervention and effective outbreak response. This review aims to provide a comprehensive analysis of viral aetiologies, mapping the circulating spectrum of common pathogens and discussing various advances in laboratory diagnosis. Analysis shows that common worldwide pathogens include herpes simplex virus (HSV) and enteroviruses. Nevertheless, Japanese encephalitis (JE) and Nipah virus remain persistent public health threats in Asian countries, including Malaysia. Furthermore, this review compares traditional laboratory methods with molecular diagnostic approaches to establish diagnostic protocols. While traditional laboratory methods which include cerebrospinal fluid analysis, viral culture and serology provide a reliable baseline, they are often hindered by limited sensitivity. In contrast, advanced platforms such as multiplex PCR and next-generation sequencing (NGS) offer rapid, high-sensitivity detection of both known and emerging pathogens. However, the transition to these technologies is often limited by high costs and technical complexity in low-resource settings. By synthesising these issues, this review contributes to scientific knowledge dissemination as well as prioritises evidence-based literature to ensure that the rapid detection capabilities of genomic platforms are utilised effectively alongside accessible conventional tools. Ultimately, this review serves as a guide for clinicians and public health authorities to enhance the laboratory diagnosis of viral meningoencephalitis in an evolving infectious landscape.
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