Ontario Ministry of Health and Long-Term Care - Health Care Providers - Program - Public Health - West Nile virus Bulletin - Volume 2 / Issue 9

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West Nile virus Bulletin : 2001 Archive
Disease Control Service Public Health Branch	Volume 2 / Issue 9 – October 2, 2001

IN THIS ISSUE

Summary of Ontario Surveillance Activities
WNv Surveillance in Ontario
Human Encephalitis Surveillance
Mosquito Surveillance

Dead Bird Surveillance
Other News
U.S. National Maps
Maps

Summary of Ontario Surveillance Activities
Human Surveillance	No confirmed cases in the year 2001.
Mosquito Surveillance	A pilot program for mosquito surveillance was initiated in six health units in early August. Windsor-Essex, Chatham-Kent, Lambton, Middlesex-London, Halton, Hamilton, Peel, Toronto, York Region and Durham are also trapping mosquitoes because of WNv activity. Results of mosquito surveillance will be available in the next bulletin.
Dead Bird surveillance	As of October 1, 2002, a total of 4,300 dead birds have been sighted and/or collected in Ontario. Of these, 2,284 were collected and sent to Guelph for consideration, and 1,458 were sent to Winnipeg for WNv testing. As of October 2, there are 76 confirmed and 1 presumptive WNv-positive birds. Sixty-four birds are American Crows and 13 birds are Blue Jays. The confirmed positive birds were found in Windsor-Essex (15), Chatham-Kent (3), Lambton (1), Middlesex-London (3), Niagara (1), Hamilton (3), Halton (3), Peel (12), Toronto (25), York Region (7), and Durham (3). The presumptive positive bird was found in Waterloo (1).
Summary of surveillance activities in other jurisdictions to date
Canada
As of October 1, 2001, there have been 6,172 dead birds reported to the WNv Dead Bird Surveillance program for all Canadian provinces.
U.S.
Human Cases :
Thirty human cases of WNv have reported in 2001.
Birds, mosquitoes, horses and other animals :
4,395 dead birds, 18 live birds, 651 WNv-positive mosquito pools, and 130 horses have tested positive for WNv.
Data Source: Canadian Cooperative Wildlife Health Centre and Health Canada.

WNv Surveillance in Ontario

The purpose of the WNv Bulletins is to provide a summary of the results of the various surveillance activities in Ontario for the current year. This issue will update WNv findings elsewhere in Canada and in the U.S.

WNv Activities in Ontario for the Year 2001

Human Encephalitis Surveillance

Health Canada has asked that key health care providers, including family and emergency room physicians, infectious disease specialists and neurologists, monitor their patients for symptoms of WNv in 2001. These health care professionals are being asked to promptly report any probable and confirmed cases of viral encephalitis to local/provincial public health authorities.

REMINDER

Physicians (Hospital, clinic, private practice) :
- Send blood samples from suspect WNv patients to the Central Public Health Laboratory (CPHL) in Toronto for serological testing to :
  
  Central Public Health Lab
  81 Resources Road
  Toronto, ON
  M9P 3T1
- Report suspect WNv cases immediately to the local Medical Officer of Health and fax "Patient Report Form"
Health Units :
- Report suspect WNv cases immediately by telephone to Dr. Margaret Fearon.
  
  Dr. Margaret Fearon
  416-235-5725 (pager : 416-715-4209)
  (After hours duty officer : 416-605-6113)
- Report suspect WNv cases immediately by telephone to Dr. Chuck Le Ber or Dr. Dean Middleton at the Ministry of Health and Long-Term Care (MOHLTC), Public Health Branch.
  
  Dr. Chuck Le Ber
  416-327-7421
  
  Dr. Dean Middleton
  416-327-7422
- Report suspect WNv cases in RDIS under the disease "viral meningitis/encephalitis" as outlined in the April 27, 2001, letter to all MOH and Communicable Disease Coordinators from Dr. Colin D'Cunha regarding Enhanced Passive Human Surveillance for West Nile Encephalitis.

Mosquito Surveillance in Ontario

Mosquito surveillance is occurring in the ten health units where birds positive for WNV have been confirmed (see Summary of ONTARIO surveillance activities : Dead Bird Surveillance) and in health units taking part in a pilot program (see Summary of ONTARIO surveillance activities : Mosquito Surveillance).

Dead Bird Surveillance

This bulletin summarizes information up to October 1, of the 40^th week of the Dead Bird Surveillance season (Week 40 = October 1 to 7, 2001). There have been a total of 4,300 reported dead bird sightings and/or submissions. Of these 4,300 birds, 2,284 were picked up and sent to the lab in Guelph for WNv testing ('pick-ups'), of which 1,458 were submitted for testing at the national laboratory in Winnipeg ('Submissions'). Maps stating the number of dead bird submissions to the lab will be provided weekly to health units.

Figure 1. Ontario Reported Number of WNv Surveillance Program Dead Birds
October 1, 2001 (N= 4,300*)
* Omitted from graph : 3 dead birds reported prior to season

Data : Canadian Cooperative Wildlife Health Centre, Health Canada August 30, 2001

Note :

Week 16 = April 16-20, 2001
Week 40 = October 1-7, 2001

Figure 2. Types of Ontario Dead Birds Reported in 2001 Season as of October 1, 2001

Figure 3. Total Number of Dead Bird Reports in 2001 by Ontario Health Units as of October 1, 2001

Note ** 'PickUps' are health unit submissions to the lab in Guelph, whereas 'Submissions' refer to dead birds sent to the lab in Winnipeg for Federal WNv Testing.

Data Source : Canadian Cooperative Wildlife Health Centre & Health Canada (September 17, 2001)

Other News

Worldwide Geographic Distribution

WNv has been described worldwide and is no longer limited to Africa and Eurasia.

North American Geographic Distribution

The American media has paid much attention to state health departments and local units with respect to their choices regarding the spraying of chemical pesticides.

Figure 4. Number of birds, mosquito pools, horses and humans that have tested positive for WNv in the U.S., 2001.

U.S. National Maps

Maps of the United States WNv Surveillance Programs can be accessed through the United States Geological Survey : Center for Integration of Natural Disaster Information (CINDI) Web site.

Maps

Acknowledgements

The contribution of the following agencies and individuals in the publication of this year's issues of the WNv Bulletin is greatly appreciated :

Ontario Ministry of Health and Long-Term Care (MOHLTC) : Public Health Branch : Dr. Colin D'Cunha, Dr. Charles Le Ber and Dr. Dean Middleton.

Canadian Cooperative Wildlife Health Centre : Dr. Ian Barker and Ron Templeman.

Health Canada : Dr. Peter Buck and Rob Meyers.



Comments, questions and suggestions about surveillance results in this bulletin should be directed to : Dr. Dean Middleton, Veterinary Consultant, Disease Control Service, Tel: 416-327-7422, E-mail : dean.middleton@moh.gov.on.ca

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