Spatiotemporal variation of notified Barmah Forest virus infections in Queensland, Australia, 1993-2001.

The spatiotemporal variations of Barmah Forest virus (BFv) infections were assessed in Queensland, Australia, between 1993 and 2001 utilizing a Geographic Information System. The notified BFv cases came from 441 localities between 1993 and 1995, 512 between 1996 and 1998, and 546 between 1999 and 2001. A statistically significant increase was observed in the number of localities from which the cases were notified by 16.1% for the period of 1996-1998 and 23.8% for 1999-2001, compared with that for 1993-1995 (chi2 (df=2) = 11.5; p < 0.01). These results indicate that there has been an expanded geographic distribution of the notified BFv infections in Queensland over the last decade. Socioecological changes may be causal factors in this expansion.