Four more cases of West Nile virus have been reported in Minnesota this past week, but the rate of infection is dropping. The latest illnesses mean that so far this year 65 cases have been reported, with one death attributed to the mosquito-borne virus in Minnesota. Nationwide, there have been more than 3,500 cases and nearly 150 deaths blamed on the disease. Health officials say that the hot summer weather across most of the nation is the likely cause for the widespread West Nile outbreak this year. As average temperatures fall, the number of new cases is expected to continue to decline. Minnesota averaged eight new cases a week in August and early September, but the rate of infection has dropped in the last two weeks. In the local area there have still been 3 cases confirmed in Brown County and one each in Sibley, Redwood, Cottonwood, Waseca and Le Sueur Counties.