RESUMEN
Primary varicella infection has typical cutaneous lesions which aid in clinical diagnosis. Infants with transplacental transfer of varicella antibody can have varied cutaneous lesions. We report a 4-month-old infant with primary varicella meningoencephalitis without cutaneous lesions whose mother had no history of varicella during antenatal or post-natal period. Diagnosis was made possible by CSF DNA PCR. Infants with encephalitis pose diagnostic challenge to clinicians in resource limited settings. Varicella encephalitis is one such aetiology for which definitive therapy with Acyclovir is available. CSF PCR is the definitive and cost-effective test for the diagnosis varicella encephalitis. In children with meningoencephalitis it is prudent to add Acyclovir empirically pending CSF viral PCR results.