Most recent weekly forecast

Click here for the West Nile Weekly, July 24th, 2017

More humid conditions, combined with increasing mosquito infection rates, have forced estimated risk to closer to historical averages for this week of the year. While we are still slightly below average, we expect a substantial number of WNV cases for the season, especially in the peak month of August. Continued mosquito collection and testing are essential, to detect whether there may be a surge in mosquito infections later than usual in the season.

Most recent seasonal forecast

Click here for the West Nile Seasonal July 24th, 2017

Based on all data available towards the end of July, we expect to see 63 cases in SD in 2017. This forecast is slightly up from that of previous weeks, owing to higher humidity and the presence of additional positive mosquito pools in counties that had not previously reported any. In every probable future we see substantial disease transmission. We note in particular that if the humidity continues to rise above historical averages, then so will the risk to human populations.


NASASouth Dakota State UniversitySD Department of Health

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).