Manitoba Health reports the analysis of the adult mosquitoes trapped for the week of June 27 found increased numbers of Culex tarsalis mosquitoes throughout southern Manitoba. None of the mosquitoes collected to date have tested positive for the West Nile virus. Preliminary trap information for the week of July 4 indicates the numbers of Culex tarsalis mosquitoes are continuing to increase throughout southern Manitoba, with some communities showing large increases in numbers.
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 increasing with the rising numbers of Culex tarsalis mosquitoes and the continued hot weather. The risk of being bitten by a mosquito carrying West Nile virus is expected to continue to increase in the coming weeks. Reducing standing water around the home can help prevent the Culex tarsalis mosquitoes from developing.
The proportion of Culex tarsalis mosquitoes collected in the traps is increasing, however, nuisance mosquitoes, which do not carry the virus, continue to make up most of the weekly trap catches. Weekly average trap counts of Culex tarsalis by regional health authority are available on the province’s West Nile virus website at www.gov.mb.ca/health/wnv.
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.
