Vector Control

Surveillance

Surveillance in Cass County consists of trapping adult mosquitoes and the subsequent identification of the mosquitoes trapped.  Surveillance can also include collecting larval samples, investigating resident complaints and conducting sweep counts in problem areas.

Mosquito traps are set prior to our typical mosquito season (May-September) and are collected and counted daily.  Apart from giving us a "heads up" for increased mosquito activity, the surveillance team identifies each mosquito trapped to a species.  This is an important part of surveillance because knowing which species are present gives field aides an idea where to look for potential breeding sites in the area (breeding habitats vary between species).  Species information also lets us know if potential disease carrying mosquitoes are present. Tests are conducted on mosquito pools in our lab to detect St. Louis Encephalitis, Western Equine Encephalitis, and West Nile Virus.

Our department uses CDC light traps, gravid traps, and New Jersey light traps. Each consists of a small motor, fan, light, and collection net.  The light attracts mosquitoes which are then blown down into the net by the fan. There are as many as thirty five traps running daily in Cass County during the mosquito season.