Weather Variability, Tides, and Barmah Forest Virus Disease in the Gladstone Region, Australia

Abstract

In this study we examined the impact of weather variability and tides on the transmission of Barmah Forest virus (BFV) disease and developed a weather-based forecasting model for BFV disease in the Gladstone region, Australia. We used seasonal autoregressive integrated moving-average (SARIMA) models to determine the contribution of weather variables to BFV transmission after the time-series data of response and explanatory variables were made stationary through seasonal differencing. We obtained data on the monthly counts of BFV cases, weather variables (e.g., mean minimum and maximum temperature, total rainfall, and mean relative humidity), high and low tides, and the population size in the Gladstone region between January 1992 and December 2001 from the Queensland Department of Health, Australian Bureau of Meteorology, Queensland Department of Transport, and Australian Bureau of Statistics, respectively. The SARIMA model shows that the 5-month moving average of minimum temperature (β = 0.15, p-value < 0.001) was statistically significantly and positively associated with BFV disease, whereas high tide in the current month (β = −1.03, p-value = 0.04) was statistically significantly and inversely associated with it. However, no significant association was found for other variables. These results may be applied to forecast the occurrence of BFV disease and to use public health resources in BFV control and prevention.

Environmental effects on parasitic disease transmission exemplified by schistosomiasis in western China

“…More generally, however, these ideas also appear quite consistent with current thinking in metapopulation ecology that concerns the distribution and persistence of populations (40). Villages act as connected patches of parasite habitat, which vary in size and quality depending on factors appearing in internal potential, such as the number of snails and human hosts.…”

“…The concepts of internal potential, its modulation by the gating effects of time-variable environmental factors, and connectivity all have analogs in the transmission of many other infectious diseases (39,40,(44)(45)(46). More generally, however, these ideas also appear quite consistent with current thinking in metapopulation ecology that concerns the distribution and persistence of populations (40).…”

“…Gating effects have long been associated with vector-borne diseases, generally in their sensitivity to weather fluctuations, for example, western equine encephalitis (39) and, more recently, Barmah Forest virus disease in Australia (40). A second notable example is the model-based malaria map for Africa proposed by Craig et al (41) that offers a contrast to the schistosomiasis case, in that their analysis focuses on the likelihood that stable transmission can occur, but based on temperature and rainfall gating effects rather than an analog of internal potential.…”

Spatial analysis of risk factors for transmission of the Barmah Forest virus in Queensland, Australia

“…Our results suggest that minimum rather than maximum temperature plays a significant role in the BFV transmission and these results are consistent with other studies (Tong and Hu, 2002;Hu et al, 2004;Naish et al, 2006;Woodruff et al, 2006;Jacups et al, 2008;Wu et al, 2009). Since some species of mosquitoes are temperature-specific in their breeding (Hardy, 1988;Mackenzie et al, 1994;Russell, 1995), the dominant species of mosquitoes in the study area may be more sensitive to minimum temperature than maximum temperature because the latter changes little in Queensland (a tropical/ sub-tropical state) particularly in summer.…”

“…However, the exact roles of each of these factors are not yet fully understood (Russell, 2009). Recently, few studies have explored the relationship between climate variability and the transmission of BFV disease in coastal Queensland in Australia (Naish et al, 2006(Naish et al, , 2009.…”