Table 2.

Summary of study procedures for central nervous system infections in Peru.

Study phase	Enrollment criteria	Clinical procedures & general laboratory testing	Pathogen-specific diagnostic testing
Phase I – Focus on HSV and a limited number of additional pathogens that cause encephalitis	Patients ≥28 days of age with acute onset (<2 weeks) of neurologic symptoms (change in level of consciousness, seizure, altered coordination, or dysphasia) plus one or more of the following: •fever (temperature ≥ 38 °C) •headache •CSF white blood cell count >5 leukocytes/ml •neuroimaging or EEG abnormalities suggestive of encephalitis	Complete blood count; CSF protein, glucose, cell count & differential; Computed tomography scan or magnetic resonance imaging when indicated. IV acyclovir provided and initiated for all patients with suspected HSV infection. Acyclovir discontinued if HSV test results were negative.	Serology: HSV-1 & 2, HIV, HTLV I & II, Treponema pallidum Blood PCR: HSV-1 & 2 CSF PCR: HSV-1 & 2 (results typically reported to provider within 72 h), Mycobacterium tuberculosis, Cryptococcus neoformans. Arboviral testing for a subset of samples (Alphavirus, Flavivirus, and Bunyavirus). Pharyngeal & rectal swabs: Enterovirus
Phase II – Inclusion of additional pathogens	Same as above	As above, plus MassTag PCR encephalitis panels	CSF PCR: RNA Panel: Nipah, Japanese encephalitis, parechovirus, Powassan, La Crosse, LCMV, St. Louis encephalitis, enteroviruses, West Nile, WEE, VEE, rabies, influenza A DNA Panel: adenoviruses, cytomegalovirus, Epstein-Barr, varicella zoster, HHV-1,2,6, H. influenzae, S. pneumoniae, N. meningitidis, L. interrogans, M. tuberculosis, T. gondii, C. albicans, C. neoformans

HSV = herpes simplex virus, EEG = electroencephalography, CSF = cerebrospinal fluid, HTLV = human T-cell lymphotropic virus, LCMV = lymphocytic choriomeningitis virus, WEE = Western equine encephalitis, VEE = Venezuelan equine encephalitis, HHV = human herpes virus.