West Nile virus and other mosquito-borne diseases national surveillance report - September 10 to September 16, 2017 (Week 37)
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West Nile Virus
Canada
Humans
During week 37, September 10 to September 16, 2017, three confirmed clinical case of West Nile Virus (WNV) from Ontario were reported to the Public Health Agency of Canada (PHAC). Retrospectively, twenty-nine additional cases were reported, twenty-eight in Ontario and one in Québec.
As of week 37, 103 clinical cases and six asymptomatic infections have been reported to the PHAC by five provinces (Ontario [98], Québec [6], Manitoba [1], Alberta [3], and British Columbia [1]. Of the 103 clinical cases, thirty-eight (37%) were classified as WNV neurological syndrome. As of September 16, five deaths associated with West Nile virus have been reported to the Public Health Agency of Canada during the 2017 season.
Mosquitoes
As of initial surveillance, 15,704 mosquito pools have been tested for WNV in Canada: Québec (1,469), Ontario (12,820), Manitoba (1,028), and Saskatchewan (387).
A total of 518 positive pools of WNV have been found in the following four provinces: 398 in Ontario [Brant County (2), Chatham-Kent (3), Durham Region (10), Eastern Ontario (5), Halton Region (35), Hamilton (29), Haliburton-Kwartha-Pine Ridge District (1), Hastings and Prince Edward Countries (13), Huron County (2), Kingston-Frontenac and Lennox and Addington (5), Lambton (2), Middlesex-London (6), Niagara Region (14), Northwestern (1), Ottawa (34), Oxford County (1), Peel (111), Perth District (6), Peterborough County-City (2), Renfrew County and District (2), Simcoe Muskoka District (2), Toronto (62), Waterloo (3), Wellington-Dufferin-Guelph (3), Windsor-Essex County (29), and York Regional (15)]; forty-one in Manitoba [(Winnipeg (13), Southern (5), Interlake Eastern (7), and Prairie Mountain (16)]; sixty-nine in Québec; and ten in Saskatchewan.
Birds
As of week 37, the Canadian Wildlife Health Cooperative has tested 150 dead birds for WNV [Quebec (86), Ontario (51), Saskatchewan (9), Manitoba (2) and British Columbia (2)]. Of these, ninety-four were positive: fifty-two in Quebec, two in Manitoba, thirty-four in Ontario, and six in Saskatchewan.
Domestic Animals
As of week 37, thirty-two horses with WNV infection were reported to the Canadian Food Inspection Agency (CFIA): four in Québec, thirteen in Ontario, six in Saskatchewan, five in Alberta, and four in British Columbia.
United States and U.S. territories
As of September 19, 2017, 875 human cases of WNV have been reported by the Centers for Disease Control and Prevention (CDC). Of these, 537 (61%) were classified as neuroinvasive disease and 338 (39%) as non-neuroinvasive disease. In addition, 143 presumptive viremic blood donors have been identified.
Detailed information can be accessed via the CDC web site.
Europe and Neighbouring Countries
As of September 14, 2017, the European Centre for Disease Prevention and Control (ECDC) reported a total of 138 (confirmed and probable) cases of West Nile fever [Austria (2), Greece (40), Hungary (10), Israel (9), Italy (27), Romania (22), and Serbia (28)].
Detailed information can be accessed via the ECDC web site.
Other Mosquito-borne Diseases
Canada
Eastern Equine Encephalitis virus
No human cases of eastern equine encephalitis virus have been reported to the Public Health Agency of Canada in 2017.
California Serogroup virus
Since January 1, 2017, fifteen human cases of laboratory-confirmed cases/exposures of California serogroup virus were diagnosed by the National Microbiology Laboratory in Canada: Alberta (2), Saskatchewan (2), Manitoba (1), Ontario (1), Quebec (8), and Nova Scotia (1). Of these cases, eleven cases were further classified as Jamestown Canyon virus and one Snowshoe hare virus.
Figure 1: Geographic distribution of WNV human cases in Canada, as of September 16, 2017
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Figure 1 text equivalent
Map showing geographic distribution of human cases of WNV in Canada.
As of surveillance week 37, ending September 16, 2017, there are 109 human cases of WNV in Canada; ninety-eight from Ontario, one from British Columbia, three from Alberta, one from Manitoba, and six from Québec.
Figure 2: West Nile virus human clinical cases and asymptomatic infections by province/territory and by report week, as of September 16, 2017
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- Figure 2 Footnote 1
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WNV clinical cases and asymptomatic infections are grouped by report week, based on episode date. Episode date could include one of the following: onset date, diagnosis date, lab sample date or reporting date.
Figure 2 text equivalent
As of week 37, ending September 16, 2017, there are 109 human clinical cases and asymptomatic infections associated with WNV in Canada.
Report Week Figure 2 Footnote * | Total | |||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | ||
British Columbia | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
Ontario | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 6 | 3 | 6 | 4 | 16 | 13 | 29 | 14 | 2 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 98 |
Alberta | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 |
Manitoba | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
Québec | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6 |
Total | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 6 | 3 | 8 | 5 | 18 | 18 | 30 | 14 | 2 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 109 |
Figure 3: West Nile virus human clinical cases and asymptomatic infections by report week for selected years, in Canada
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- Figure 3 Footnote 1
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WNV clinical cases and asymptomatic infections are grouped by report week, based on episode date. Episode date could include one of the following: onset date, diagnosis date, lab sample date or reporting date.
Figure 3 text equivalent
Report Week Figure 3 Footnote * | Total | ||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | ||
2017 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 6 | 3 | 8 | 5 | 18 | 18 | 30 | 14 | 2 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 109 |
2016 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 5 | 5 | 14 | 11 | 16 | 12 | 9 | 6 | 15 | 5 | 0 | 0 | 3 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 106 |
2014 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 4 | 3 | 5 | 6 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 22 |
2012 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 3 | 5 | 11 | 16 | 27 | 53 | 63 | 57 | 43 | 43 | 45 | 24 | 30 | 14 | 9 | 5 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 450 |
2007 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 2 | 3 | 4 | 11 | 35 | 36 | 72 | 139 | 424 | 471 | 443 | 287 | 182 | 116 | 71 | 30 | 18 | 10 | 11 | 5 | 4 | 2 | 0 | 0 | 0 | 0 | 0 | 2,378 |
2003 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 5 | 11 | 9 | 27 | 66 | 249 | 323 | 324 | 178 | 107 | 82 | 37 | 14 | 8 | 4 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 1,450 |
Province/Territory | Week 37: September 10 to September 16, 2017 | |||||
---|---|---|---|---|---|---|
WNV Cases | Total clinical casesTable 1 Footnote 1 | # of travel related WNV casesTable 1 Footnote 2 | # of asymptomatic WNV infectionsTable 1 Footnote 3 | |||
Neurological syndrome | Non-Neurological syndrome | Unclassified / Unspecified | ||||
Newfoundland and Labrador | 0 | 0 | 0 | 0 | 0 | 0 |
Prince Edward Island | 0 | 0 | 0 | 0 | 0 | 0 |
Nova Scotia | 0 | 0 | 0 | 0 | 0 | 0 |
New Brunswick | 0 | 0 | 0 | 0 | 0 | 0 |
Québec | 0 | 0 | 0 | 0 | 0 | 0 |
Ontario | 1 | 0 | 2 | 3 | 0 | 0 |
Manitoba | 0 | 0 | 0 | 0 | 0 | 0 |
SaskatchewanTable 1 Footnote 4 | 0 | - | - | - | - | - |
Alberta | 0 | 0 | 0 | 0 | 0 | 0 |
British Columbia | 0 | 0 | 0 | 0 | 0 | 0 |
Yukon Territory | 0 | 0 | 0 | 0 | 0 | 0 |
Northwest Territories | 0 | 0 | 0 | 0 | 0 | 0 |
Nunavut | 0 | 0 | 0 | 0 | 0 | 0 |
Total | 1 | 0 | 2 | 3 | 0 | 0 |
Year to date: January 1 to September 16, 2017 | ||||||
Newfoundland and Labrador | 0 | 0 | 0 | 0 | 0 | 0 |
Prince Edward Island | 0 | 0 | 0 | 0 | 0 | 0 |
Nova Scotia | 0 | 0 | 0 | 0 | 0 | 0 |
New Brunswick | 0 | 0 | 0 | 0 | 0 | 0 |
Québec | 4 | 1 | 0 | 5 | 0 | 1 |
Ontario | 31 | 30 | 33 | 94 | 15 | 4 |
Manitoba | 1 | 0 | 0 | 1 | 0 | 0 |
SaskatchewanTable 1 Footnote 4 | 0 | - | - | - | - | - |
Alberta | 2 | 1 | 0 | 3 | 1 | 0 |
British Columbia | 0 | 0 | 0 | 0 | 0 | 1 |
Yukon Territory | 0 | 0 | 0 | 0 | 0 | 0 |
Northwest Territories | 0 | 0 | 0 | 0 | 0 | 0 |
Nunavut | 0 | 0 | 0 | 0 | 0 | 0 |
Total | 38 | 32 | 33 | 103 | 16 | 6 |
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Province | Year to date: January 1 to September 16, 2017 | ||
---|---|---|---|
Number of positive mosquito pools | Number of mosquito pools tested | Percentage of positive mosquito pools (%) | |
Quebec | 69 | 1,469 | 4.70 |
Ontario | 398 | 12,820 | 3.10 |
Manitoba | 41 | 1,028 | 3.99 |
Saskatchewan | 10 | 387 | 2.58 |
Alberta | - | - | - |
British Columbia | - | - | - |
Newfoundland and Labrador | - | - | - |
Prince Edward Island | - | - | - |
Nova Scotia | - | - | - |
New Brunswick | - | - | - |
Yukon Territory | - | - | - |
Northwest Territory | - | - | - |
Nunavut | - | - | - |
Total | 518 | 15,704 | 3.30 |
Province / Territory | Report week of 2017 | Total | |||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | ||
Québec | - | - | - | - | - | - | - | - | 147 | 147 | 147 | 147 | 147 | 147 | 147 | 146 | 147 | 147 | 0 | 1,469 | |||
Ontario | 13 | 15 | 43 | 84 | 194 | 299 | 718 | 794 | 964 | 1,003 | 1,037 | 1,053 | 1,168 | 1,015 | 1,116 | 993 | 931 | 746 | 634 | 12,820 | |||
Manitoba | - | - | - | - | 15 | 45 | 48 | 16 | 60 | 93 | 96 | 113 | 178 | 122 | 86 | 104 | 25 | 20 | 7 | 1,028 | |||
Saskatchewan | - | - | - | - | 6 | 20 | 11 | 18 | 25 | 31 | 38 | 46 | 61 | 52 | 39 | 40 | 0 | 0 | 0 | 387 | |||
Alberta | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
British Columbia | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Newfoundland and Labrador | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Prince Edward Island | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Nova Scotia | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
New Brunswick | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Yukon Territory | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Northwest Territories | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Nunavut | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | |||||||
Total | 13 | 15 | 43 | 84 | 215 | 364 | 777 | 828 | 1,196 | 1,274 | 1,318 | 1,359 | 1,554 | 1,336 | 1,388 | 1,283 | 1,103 | 913 | 641 | 0 | 0 | 0 | 15,704 |
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Figure 4: Reported number of dead birds tested positive for WNV by province/territory and by report week, 2017 season in CanadaFigure 4 Footnote ¶
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- Figure 4 Footnote 1
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Not all provinces are conducting dead bird surveillance as part of their own WNV surveillance program. However, WNV positive dead birds may be identified through the National Wildlife Disease Surveillance Program of the Canadian Wildlife Health Cooperative.
Figure 4 text equivalent
As of week 37, ending September 16 in 2017, there are ninety-four WNV cases in birds, in Canada.
Report Week | ||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | Total | |
Manitoba | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 |
Ontario | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 1 | 0 | 0 | 2 | 5 | 1 | 7 | 4 | 3 | 5 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 34 |
Québec | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 4 | 3 | 9 | 10 | 7 | 7 | 6 | 5 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 52 |
Saskatchewan | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 3 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6 |
Total | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 1 | 4 | 3 | 13 | 16 | 8 | 17 | 12 | 8 | 6 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 94 |
Figure 5: Percentage of dead birds tested positive for WNV by report week in 2012, 2015, 2016, 2017 and number of dead birds tested positive, by report week, 2017, in CanadaFigure 5 Footnote ¶
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- Figure 5 Footnote 1
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Not all provinces are conducting dead bird surveillance as part of their own WNV surveillance program. However, WNV positive dead birds may be identified through the National Wildlife Disease Surveillance Program of the Canadian Wildlife Health Cooperative.
Figure 5 text equivalent
Report Weeks | Total | |||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | ||
2013 Percentage positive | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 20 | 0 | 0 | 56 | 20 | 45 | 47 | 38 | 38 | 75 | 69 | 67 | 60 | 67 | 0 | 50 | 100 | 0 | 17 | 0 | 0 | 0 | 0 | 0 | 43.5% |
2014 Percentage positive | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 15 | 20 | 29 | 31 | 0 | 27 | 75 | 0 | 20 | 0 | 50 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 20.4% |
2015 Percentage positive | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 100 | 0 | 0 | 0 | 100 | 83 | 60 | 73 | 0 | 25 | 67 | 83 | 57 | 50 | 80 | 67 | 0 | 21 | 0 | 0 | 0 | 0 | 50 | 0 | 0 | 0 | 51.0% |
2016 Percentage positive | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 33 | 50 | 23 | 25 | 80 | 43 | 43 | 20 | 36 | 0 | 80 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 26.2% |
2017 Percentage positive | - | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 100 | 33 | 50 | 100 | 33 | 87 | 84 | 62 | 77 | 67 | 89 | 86 | 100 | |||||||||||||
2017 Number positive | - | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 1 | 4 | 3 | 13 | 16 | 8 | 17 | 12 | 8 | 6 | 1 | 94 |
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