Thanks again for allowing us to come down to sample for mosquitoes in Rochester. It was great to get this effort going, and one we hope to continue in the future. As promised, below is a summary of our visit. I should mention up front that we did not find any Asian tiger mosquitoes (Aedes albopictus, potential vector for Zika virus). What we did find were lots of common pest mosquito species, and a couple of mosquito species capable of transmitting a virus endemic to Minnesota.
Adult samples were collected using a hand held, battery operated vacuum called a “Sucomatic.” It basically sucks adult mosquitoes into a net that’s connected to a vacuum. We then euthanize the adult mosquitoes and identify them under a microscope. Larval samples are collected from water holding containers, mainly tires. Larval samples are allowed to mature into adults in special rearing containers, at which point we euthanized and identify. We sampled for mosquitoes using one or both of these methods at 5 locations:
1. Heartland Tire
· Adult sample: Mostly pest mosquito species (mosquitoes that bite but do not transmit any diseases to humans), one Culex genus mosquito that can help maintain West Nile virus in nature but does not typically feed on humans, and a handful of Aedes triseriatus mosquitoes. Ae. triseriatus mosquitoes are the primary vector of La Crosse virus in Minnesota
· Larval sample: A handful of Aedes triseriatus mosquitoes
2. Homestead Park
· Adult sample: Lots of pest mosquitoes, and a handful each of Aedes triseriatus and Aedes japonicus mosquitoes. Ae. japonicus is a potential vector of La Crosse virus
3. Cooke Park
· Adult sample: A single Aedes japonicus mosquito captured
· Larval sample: A few Aedes triseriatus mosquitoes captured
4. Indian Heights Park
· Adult sample: Mostly pest mosquitoes, a few Culex genus mosquitoes that can help maintain West Nile virus in nature but does not typically feed on humans, and then a handful each of Aedes triseriatus and Aedes japonicus
5. Bauer Built Tire
· Larval sample: Both Aedes triseriatus and Aedes japonicus
We were not surprised to find Ae. triseriatus (also known as the “tree hole” mosquito) in most locations, as they are well-established in southeastern Minnesota. This mosquito is the primary vector of La Crosse virus, which can cause severe illness in children. Another potential vector of La Crosse virus is the Aedes japonicus mosquito. We did not collect enough of either of these mosquito species to test for virus, but we’d be happy to work with the city and local public health to develop prevention messages for businesses and citizens of Rochester. This would include encouraging annual springtime property clean up and regular emptying/elimination water holding containers on properties, to reduce the risk of disease in the area.
Thanks again! Please feel free to email or call if you have any questions or want to talk mosquitoes. J