Dry conditions, combined with low mosquito infection rates, continue to push our estimates below average, but this only places us in the lowest 25% of all years on record. In other words, while risk is low, we still expect a substantial number of WNV cases, many contracting the infection this week, and continue to recommend mosquito control.
Most recent weekly forecast
Most recent seasonal forecast
Moving towards the end of July, 2017 is still estimated to be an average to below-average year for WNV in South Dakota. At this time, we expect about 58 human cases in 2017. This forecast is based primarily on very low humidity, which is inhospitable to mosquitoes, and the many WNV-negative mosquito pools that are being reported throughout the state. The situation may change rapidly, and WNV may only be late this year, rather than below average. Transmission to human populations is still possible even where no positive pools have been found.
South Dakota State University has partnered with the South Dakota Department of Health to implement a program of West Nile virus (WNV) research that will support public health decision makers at the state level and mosquito control programs at the local level. Major activities include mosquito surveillance and testing for WNV, monitoring environmental risk factors using data from earth observing satellites, and using this information to predict the risk of WNV to humans across the state. This work is supported in part by a grant from the NASA Applied Sciences Public Health and Air Quality Program (NNX15AF74G).