Sindbis virus has been isolated in India, Uganda, South Africa, Philippines, Egypt, Malaya, and Australia and is one of the few, if not the only, arbovirus that has been found in all four of the zoogeographic regions.6 It would therefore not be surprising if Sindbis virus were found to occur in New Zealand. However, the differences reported here between Whataroa virus and strains of Sindbis virus appear to be far greater than the slight antigenic differences between the strains of Sindbis isolated in the various geographic regions described by Casals.7 It is therefore considered that Whataroa virus should be regarded as a new and distinct group A arthropod-borne virus.
Whataroa virus, a group A arbovirus isolated in South Westland, New Zealand, in 1962, has been compared serologically with other group A agents and especially with strains of Sindbis virus to which it appears to be most closely related. The results of these studies show that Whataroa is distinct from Sindbis and should be considered a separate member of group A of the arthropodborne viruses.
Microbiology Department, University of Otago Medical School, Dunedin, New Zealand.
The Yale Arbovirus Research Unit, New Haven, Connecticut.