Manitoba Health reports the analysis of the adult mosquitoes trapped for the week of June 20 found increased numbers of Culex tarsalis mosquitoes in some communities in southern Manitoba but overall numbers remained low. None of the mosquitoes collected to date have tested positive for the West Nile virus. Preliminary trap information for the week of June 27 indicate the numbers of Culex tarsalis mosquitoes have increased throughout southern Manitoba. Although the numbers of Culex tarsalis are still relatively low, numbers are anticipated to continue to increase in the coming weeks.
Culex tarsalis mosquitoes are the mosquitoes most likely to carry the West Nile virus. It is possible there are some infected Culex tarsalis mosquitoes in southern Manitoba at this time; the risk of exposure to West Nile virus is beginning to increase. The risk of being bitten by a mosquito carrying West Nile virus is expected to continue to increase in the coming weeks.
Most of the mosquitoes collected have been nuisance mosquitoes, which do not carry the virus. Weekly average trap counts of Culex tarsalis by regional health authority are available on the province’s West Nile virus website.
The province offers a cost-shared larviciding program for municipalities and communities to take steps to help control Culex tarsalis mosquitoes. Under the program, 75 per cent of costs are covered by the province and 25 per cent are covered by the participating community. To date this year, 55 communities are participating in the program.
Information on the risk of West Nile virus will continue to be provided to the public throughout the summer in a media campaign and at various fairs and festivals. Manitobans can also check the West Nile virus website regularly for up-to-date data and information.