Shasta Mosquito and Vector Control District

22 “New Jersey” Light traps are distributed throughout the District from April through October. These traps are collected weekly and the mosquitoes are identified and counted to provide an accurate assessment of mosquito populations throughout the District all through the mosquito season. Since encephalitis diseases occur more frequently in bird populations than among humans, five sentinel chicken flocks are kept in different areas of the District to monitor encephalitis virus activity. Blood samples are taken from the chickens every two weeks and sent to a state lab to be tested for the presence of antibodies to encephalitis viruses.

In addition, the District runs 21 CO2 baited EVS traps throughout the Shasta County aimed at collecting live mosquitoes that are sent to the state lab to be directly tested for the presence of encephalitis viruses. Detection of virus activity in the district prompts intensified and focused mosquito control to ensure the protection of the health of residents in areas where the risk of the spread of the disease is high. 

Finally, the District deploys in various locations “Gravid traps”. Designed in the early 1980s to collect mosquitoes that are “gravid” or carrying eggs; the female mosquitoes seek out the attractive bait in the trap and get sucked into the trap by a fan. This type of trap is very good for collecting Cx. Pipiens mosquitoes, a potential vector of West Nile Virus.