Volume 18, Number 5—May 2012
Characterization of Virulent West Nile Virus Kunjin Strain, Australia, 2011
|Horse serum samples||% Inhibition of CPE/growth†
|WNVNSW2011, 100 infectious units
||WNVKUN, 26 infectious units
||WNVNY99, 32 infectious units
*Determined, as described (14), by microneutralization assay in Vero cells. WNV, West Nile virus; CPE, cytopathic effect; NSW, New South Wales; KUN, Kunjin; NY, New York; NT, Northern Territory; mAb, monoclonal antibody.
†Boldface indicates serum samples with >4-fold difference in titer between virus strains.
‡Determined by using a microscope to assess the level of CPE in each well compared with that in control wells.
§Determined by the absence of viral antigen in the cell monolayer of each well when tested with a WNV-reactive mAb in ELISA.
¶Samples from uninfected horses.
#Samples from horses infected with WNV during the 2011 outbreak in New South Wales, Australia.
**Samples from horses infected with WNVKUN in Northern Territory, Australia.
††Samples from horses infected with WNV in the United States.
‡‡This mAb has potent WNV-neutralizing activity (11).
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1These authors contributed equally to the major technical aspects of this research.
2These authors served as joint senior authors.