Health Canada's First Nations and Inuit Health Branch (FNIHB), in collaboration with First Nations authorities, carries out West Nile virus surveillance, public education and mosquito control activities in First Nations communities south of 60°. First Nations and Inuit Health regional offices work in cooperation with its provincial and territorial counterparts to ensure that regional West Nile virus activities are consistent and integrated with those in the provinces and territories wherever possible.
Monitoring West Nile virus activity through dead bird and mosquito surveillance and testing:
Surveillance activities in First Nations communities focus on birds, mosquitoes and humans. The objective of West Nile virus surveillance activities is to detect the presence of West Nile virus as early as possible in a given community so that decisions on the appropriate response activities can be made in a timely manner. If West Nile virus is detected in a First Nations community, health officials alert the Chief and Council.
Finding a dead bird that tests positive for West Nile virus is one of the signs that the virus has spread to a given area. Residents can help detect West Nile virus in their community by contacting their Community Health Centre or Nursing Station to report dead birds. As a general precaution, residents are reminded to always wear rubber gloves when touching any dead birds or animals, as they may carry disease.
If a dead bird is reported on a reserve, First Nations and Inuit Health regional health authorities (for example, Environmental Health Officers) may coordinate the collection of the specimen and forward it to the appropriate laboratory for testing. Testing for West Nile virus is conducted at the Canadian Cooperative Wildlife Health Centres, or provincial and federal laboratories, and results are forwarded to EHOs.
Birds that may be collected for West Nile virus testing include crows, jays, ravens and magpies. However, this varies from region to region, as well as from province to province. Some provinces have reduced or discontinued West Nile virus bird surveillance, and Health Canada works closely with provinces to ensure consistency of bird surveillance practices. First Nations residents can contact their Environmental Health Officer, Community Health Centre or Nursing Station for information on what (if any) birds are being collected in their region.
Mosquito surveillance establishes what mosquito species are present and their relative abundance over the season. Mosquitoes are tested for West Nile virus to determine if there is West Nile virus activity in the community and if mosquito control activities may be necessary.
Health care providers in First Nations communities watch for symptoms of West Nile virus in their patients, and request laboratory tests when appropriate. They report probable or confirmed cases to local and provincial health authorities and to First Nations and Inuit Health regional staff.
Depending on the results of laboratory testing, First Nations and Inuit Health regional staff and Chiefs and Councils determine if, when and where mosquito control activities to reduce the risk of West Nile virus transmission to humans should be used. Positive test results are compiled by the FNIH regional office and at the FNIHB national level for tracking purposes.
Low risk areas are defined as areas where there is the absence of confirmed West Nile virus infection in a bird, mammal, mosquito pool or human and West Nile virus activity is unlikely, possible or unknown.
Medium risk areas are defined as areas where there has been detection of West Nile virus activity in a First Nations community during the previous year, or within neighbouring jurisdiction in the current year, based on laboratory-confirmed identification in a bird, mammal, mosquito pool or human.
High risk areas are defined as areas where there has been detection of West Nile virus activity in a First Nations community in a current year, based on laboratory-confirmed identification of the virus in a bird, mammal, mosquito pool or human.
Note that as "jurisdiction" is defined differently in each province, First Nations and Inuit Health regional staff will follow each province's West Nile virus definition for jurisdiction, as outlined in provincial guidelines.
Health Canada's First Nations and Inuit Health Branch inform First Nations communities about West Nile virus and the steps residents can take to protect themselves. As part of the West Nile virus public education campaign, First Nations and Inuit Health regional staff may provide information sessions for First Nations residents, leaders, community workers or health care workers upon request. Information focuses on the following:
First Nations residents can reduce their risk of being bitten by wearing light-coloured clothing with long sleeves, pants, socks and a hat when outdoors; limiting the time spent outdoors at dawn and dusk when mosquitoes are most active; using insect repellents that contain DEET or other approved ingredients; and ensuring that screens and windows on homes, tents and hunting shelters are in good repair and free of holes.
First Nations residents can help reduce mosquito populations around their homes and communities by reducing or removing standing water from old tires, small boats and other outdoor items. Water in outdoor pet dishes should also be replaced at least twice a week.
Recommending to Chiefs and Councils appropriate public health interventions to control West Nile virus activity in a First Nations community:
First Nations and Inuit Health regional staff advise Chiefs and Councils, as well as other federal government departments, on any emerging needs for West Nile virus public health control measures in First Nations communities, including the use of insecticides.
First Nations and Inuit Health regional staff consult with their provincial and territorial counterparts to ensure that regional activities to address West Nile virus, including the use of insecticides, are consistent and integrated with provincial activities, wherever possible.
In areas where the risk of contracting West Nile virus is medium or high (based on reported cases of West Nile virus in humans, animals, or birds, or its presence in mosquito populations), First Nations and Inuit Health regional staff make a recommendation to the Band leadership on interventions to be taken. A Band Council Resolution authorizing the use of insecticides is sought before proceeding with any such activity.
Insecticides, including larvicides and adulticides, are used to reduce the population of mosquitoes that could be capable of transmitting West Nile virus to humans. Larvicides may be used in First Nations communities where there is a medium or high risk of humans contracting West Nile virus.
Adulticides are considered only as a last resort to prevent human infections in instances where there is significant risk to human health from West Nile virus and where prevention or mosquito control measures have failed or would clearly be inadequate to stop the spread of the virus.
Other preventive measures (for example the use of repellents, avoidance strategies and source reduction) are used before and during any insecticide campaign.
First Nations residents looking for information about specific West Nile activity in their area, including surveillance activities and case counts, and proposed prevention and response plans, can contact their local Environmental Health Officer, Community Health Centre or Nursing Station.
For more information on West Nile virus, please visit www.westnile.gc.ca or call 1-800 O CANADA.
Further information on approved insect repellents and ways to reduce mosquito populations is available through the Pest Management Regulatory Agency (PMRA) section.