Nipah viral genome loads and virus isolation from brain, lungs and blood days 0–15 post-exposure. Twelve month old BALB/c mice were intranasally exposed to either Nipah Virus Malaysia (white circles) or Nipah Virus Bangladesh (grey circles). Two mice per viral strain were euthanased and sampled at 48 hour intervals up to day 12 post exposure and at day 15 post exposure, as indicated (Days post exposure). Nipah viral RNA was extracted from tissue samples and analysed in triplicate using qPCR assay detecting Nipah viral nucleocapsid protein RNA and 18S rRNA. Virus isolation was attempted on all tissues positive for viral RNA. Successful isolations are indicated by a black point (.) within the circles.