West Nile Virus national surveillance report: July 1 - 7, 2018

Organization: Public Health Agency of Canada

Published: July 23 2018

Related Topics

• West Nile Virus

West Nile Virus - Week 27 2018

Canada

Human

As of surveillance week 27, ending on July 7, 2018, no human cases of West Nile virus (WNV) have been reported to the Public Health Agency of Canada (PHAC).

Mosquito

To date (week 27), the PHAC has been notified of 2,746 mosquito pools tested for WNV: 149 in Saskatchewan, 496 in Manitoba, 1,797 in Ontario, and 304 in Québec. Of these, five positive mosquito pools were found: four in Manitoba (Winnipeg (1), Interlake-Eastern ( 3)) and one in Ontario (Windsor-Essex County).

Wild Bird

As of week 27, a total of fourteen dead wild birds have been tested for WNV by the Canadian Wildlife Health Cooperative (CWHC) and Manitoba Agriculture: one in Alberta two in Saskatchewan, three in Manitoba, seven in Ontario and one in Québec. Of these, three dead wild birds were positive for WNV in the Interlake-Eastern Regional Health Authority, Manitoba.

Equine

The Canadian Food Inspection Agency (CFIA) has not reported domestic animals tested positive for WNV, since the start of the 2018 WNV season.

United States and U.S. territories

As of July 10, fourteen human cases of WNV have been reported to the Centers for Disease Control and Prevention. Of these, seven (50%) were classified as neuroinvasive disease and seven (50%) as non-neuroinvasive disease. No deaths have been reported. In addition, two presumptive viremic blood donors have been identified.

Europe and Neighboring Countries

As of July 5, eleven human cases of West Nile fever have been reported to the European Centre for Disease Prevention and Control in the following countries: Austria (1), Greece( 7), Italy(1), and Serbia(2). No deaths have been reported.

Weekly updates: 2018 West Nile fever transmission season

Other Mosquito-borne Diseases - Week 27 2018

Canada

Eastern Equine Encephalitis virus

No human cases of Eastern Equine Encephalitis virus (EEEV) have been reported to the PHAC, since the 2018 season.

California Serogroup virus

In surveillance week 27, no human cases/exposures of California serogroup virus were diagnosed by the National Microbiology Laboratory in the Public Health Agency of Canada.

Figure and tables

Figure 1 - Text description

Map showing geographic distribution of human cases of West Nile virus (WNV) in Canada.

As of July 7, 2018, no human cases of WNV were reported to the Public Health Agency of Canada (PHAC).

Figure 2 note ±: 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 description

As of week 27, ending July 7, 2018, there are no human clinical cases and asymptomatic infections associated with WNV in Canada.

Table showing human clinical cases and asymptomatic infections associated with WNV in Canada, by province or territory and by week monitoring, dated July 7, 2018

Province / Territory	Report Weekfigure 2 table note ±																									Total
	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
British Columbia	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Alberta	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Manitoba	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Ontario	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Québec	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Total	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
'-' = Not available. Figure 2 table notes Figure 2 table note ± 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. Return to figure 2 table note ± referrer

Figure 3 note *: 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 description

Table showing WNV human clinical cases and asymptomatic infections in Canada, by report week for selected years

Year	Report Weekfigure 3 table note *																									Total
	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
2018	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
2017	0	0	1	0	1	1	7	3	8	10	26	31	31	27	13	16	7	8	4	1	1	3	0	0	0	200
2016	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	105
2014	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	22
2012	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	450
2007	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	2,378
2003	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	1,450
'-' = Not available. Figure 3 table notes Figure 3 table note * 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. Return to figure 3 table note * referrer

Table 1: WNV human clinical cases and asymptomatic infections in Canada by reported weeks and year to date, 2018

Province/Territory	Clinical Cases			Total clinical casestable 1 note 1	Total travel-related casestable 1 note 2	Total asymptomatic infectionstable 1 note 3
	Neurological syndrome	Non-neurological syndrome	Unclassified/ Unspecified
Week 27: July 1 to July 7, 2018
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	0	0	0	0	0	0
Manitoba	0	0	0	0	0	0
Saskatchewantable 1 note 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 Territory	0	0	0	0	0	0
Nunavut	0	0	0	0	0	0
Total	0	0	0	0	0	0
Year to date: January 1 to July 7, 2018
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	0	0	0	0	0	0
Manitoba	0	0	0	0	0	0
Saskatchewantable 1 note 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 Territory	0	0	0	0	0	0
Nunavut	0	0	0	0	0	0
Total	0	0	0	0	0	0
'-' = Not available. Table 1 notes Table 1 note 1 Total clinical cases are the sum of confirmed and probable: WNV neurological and non-neurological syndromes, along with any unclassified or unspecified cases. Return to table 1 note 1 referrer Table 1 note 2 Likely related to travel outside the Province/Territory. These cases are included in either the total clinical cases or WNV asymptomatic infections. Return to table 1 note 2 referrer Table 1 note 3 Satisfies WNV diagnostic test criteria in the absence of clinical criteria. This category could include asymptomatic blood donors whose blood is screened using a nucleic acid amplification test, by blood operators (i.e. Canadian Blood Services or Hema-Quebec) and is subsequently brought to the attention of public health officials. Blood operators in Canada perform a supplementary WNV specific nucleic acid amplification test following any positive donor screen test result. Return to table 1 note 3 referrer Table 1 note 4 Saskatchewan provides counts of WNV neurological syndrome cases only. Return to table 1 note 4 referrer

Table 2: WNV mosquito surveillance^{table 2 note *} in Canada, as of July 7, 2018

Province / Territory	Number of positive mosquito pools	Number of mosquito pools tested	Percentage of positive mosquito pools (%)
Saskatchewan	0	149	0.00
Manitoba	4	496	0.81
Ontario	1	1,797	0.06
Québec	0	304	0.00
Total	5	2,746	0.18
Table 2 notes Table 2 note 1 Mosquito surveillance data is reported by the following four provinces: Quebec, Ontario, Manitoba, and Saskatchewan. Return to table 2 note * referrer

Table 3: Total number of WNV mosquito pools tested by report week and by province/ territory, 2018^{table 3 note ‡}

Province	Report Week																		Total
	23	24	25	26	27	28	29	30	31	32	33	34	35	36	37	38	39	40
Saskatchewan	15	18	17	45	54	-	-	-	-	-	-	-	-	-	-	-	-	-	149
Manitoba	39	89	107	124	122	-	-	-	-	-	-	-	-	-	-	-	-	-	496
Ontario	-	-	-	842	955	-	-	-	-	-	-	-	-	-	-	-	-	-	1,797
Québec	69	77	105	53	-	-	-	-	-	-	-	-	-	-	-	-	-	-	304
Total	123	184	229	1,064	1,131	-	-	-	-	-	-	-	-	-	-	-	-	-	2,746
'-' = Not available. Table 3 notes Table 3 note 1 Detailed West Nile Virus mosquito surveillance data can be accessed through provincial/territorial websites. Return to table 3 note ‡ referrer

Figure 4 notes

Figure 4 note *

Not all provinces conduct dead wild bird surveillance as part of their respective WNV surveillance program. However, WNV positive dead wild birds may be identified through the National Wildlife Disease Surveillance Program, CWHC.

Return to figure 4 note * referrer

Figure 4 - Text description

As of week 27, ending July 7, 2018, there are three WNV cases in birds, in Canada.

Table showing the reported number of dead birds tested positive for WNV in Canada, by province/territory and by report week, 2018 season.

Province	Jun					Jul				Aug					Sept				Oct				Nov					Total
	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
Québec	0	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Ontario	0	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Manitoba	0	0	3	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	3
Saskatchewan	0	0	0	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	0
Total	0	0	3	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	3
'-' = Not available.

Figure 5 notes

Figure 5 note *

Not all provinces conduct dead wild bird surveillance as part of their respective WNV surveillance program. However, WNV positive dead wild birds may be identified through the National Wildlife Disease Surveillance Program, CWHC.

Return to figure 5 note * referrer

Figure 5 - Text description

Table showing percentage of dead wild birds positive for WNV by report week in 2012-2018 and number of dead birds positive in Canada by report week, 2018*

		Jun					Jul				Aug					Sept				Oct				Nov
		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
2013	Percentage positive	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
2014	Percentage positive	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
2015	Percentage positive	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
2016	Percentage positive	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
2017	Percentage positive	0	0	0	100	25	50	100	33	87	86	53	77	74	87	80	71	57	31	43	33	20	50	50	0	0	0
2018	Percentage positive	0	0	100	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
2018	Number positive	0	0	3	0	0	0	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
'-' = Not available.