Hendra may transmit in prodromal stage

Scientists at a CSIRO lab in Victoria monitored three mares exposed to the virus. The horses had a nasal discharge containing virus DNA after two days, although other symptoms did not emerge until 5–7 days after exposure. 

“Nasal secretions of asymptomatic horses may pose a transmission risk during the early phase of disease that precedes viraemia, fever, or other discernible clinical signs,” the authors said.

This risk was still “relatively low” compared to the immediate pre-symptomatic and symptomatic stages of infection.

Emerg Infec Dis 2011; online 31 October