Table 3. Differential diagnosis of Nipah Virus disease.

Differential diagnoses	Differentiating features
1) Cerebral Malaria	High grade fever associated with chills and rigors hrombocytopenia, hepato-renal dysfunction, hypoglycemia Diagnosis by rapid antigen detection kits/peripheral smear/quantitative buffy coat examination/nucleic acid amplification
2) Scrub typhus	Presence of eschar Leucocytosis, thrombocytopenia, hepato-renal dysfunction Post-monsoon (seasonal predilection) Immunofluorescence assay for diagnosis
3) Leptospirosis	Hepatitis more common Post-monsoon (seasonal predilection) Diagnosis by blood culture/nucleic acid amplification/serology
4) Dengue encephalitis	Serositis and thrombocytopenia Generalised eryhtematous blanching rash Seasonal predilection Diagnosis by NS1 antigen/nucleic acid amplification in first 5 days and IgM ELISA after 5 days
5) Herpes meningoencephalitis	Fronto-temporal lobe involvement Diagnosis by nucleic acid amplification
6) Bacterial meningitis	CSF pleocytosis with neutrophilic predominance and raised proteins with low sugar Diagnosis by blood and CSF culture and latex agglutination or nucleic acid amplification in CSF
7) Japanese encephalitis	Pigs (amplifying hosts) are healthy Low secondary attack rates Children are affected more than adults Basal ganglia involvement on imaging
8) Measles	More in children Cough, coryza, conjunctivitis Maculopapular rash on face and head
9) Rabies	Diagnosis is clinical and by serology History of dog bite/bat exposure Hydrophobia/aerophobia Diagnosis by immunofluorescence staining for viral antigen on the biopsy from the nape of the neck