With the State Health Dept. warning Jackson residents to make a special effort to avoid mosquito bites because of the danger of West Nile virus, you may wonder why Hinds County continues to be the state's hot spot for West Nile. It's not just because it's the most populous county. Harrison County, with the second largest population, hasn't had a West Nile case since 2014. The local mosquito population is another big factor. And it's not just the number of mosquitoes-- it's also the type of mosquito.