Mosquito populations in Minnesota are on the decline this fall, including the ones that transmit the West Nile virus. The peak risk period usually runs from mid-July to mid-September. The state Health Department’s Dave Neitzel says the number of human West Nile cases this season mirrors 2012, with 61 West Nile cases reported and two fatalities this year. Last year, there were 70 cases total. Neitzel says they are still analyzing reports from late August and September. Minnesota had a record-low two West Nile cases in 2011.