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Annual Report

FAO/ OIE/ WHO Questionnaire - 2004
Canada

Written report to the Office International des Épizooties (OIE)

Annual Written Report

I. New activities of the veterinary services

1) Announcement of the establishment of a new College of Veterinary Medicine

In June 2004, the Province of Alberta announced funding for the establishment of a new faculty of veterinary medicine in Canada to be constructed on the campus of the University of Calgary. The rationale for the investment is based on a burgeoning demand for veterinarians in increasingly under-serviced areas of the profession including academia, regulatory medicine, advanced laboratory and research applications and food animal population medicine. Situating the new veterinary school at the University of Calgary allows for co-location with the existing school of human medicine located on the campus in an effort to maximize synergies in comparative medicine and zoonoses. The new school is scheduled to receive its first undergraduate class in September 2006 and will be the fifth school of veterinary medicine in Canada joining those previously established: Ontario Veterinary College, University of Guelph; École de médecine vétérinaire Saint-Hyacinthe, University of Montreal; Western College of Veterinary Medicine, University of Saskatchewan; Atlantic Veterinary College, University of Prince Edward Island.

2) Creation of a dedicated Office of the Chief Veterinary Officer of Canada

In July 2004, the President of the Canadian Food Inspection Agency announced the creation of a dedicated Office of the Chief Veterinary Officer of Canada. The establishment of this Office was in response to the recognition of the complex jurisdictional and multi-faceted nature of the emerging global threat to the environment and the increased need for collaboration beyond national borders to address food safety, animal and veterinary public health issues in a synergistic and effective manner. Within the Office of the Chief Veterinary Officer, who also serves as

Canada’s delegate to the World Organisation for Animal Health (OIE), it is proposed to staff a dedicated position to raise awareness within the country of the work of the OIE and understanding of its work program and standard setting processes, increase the involvement of industry, provinces, academia and other federal departments in the contribution of science based comments on proposed Code changes and coordinate with public health officials consistent positions with Canada’s inputs to the World Health Organization and Codex Alimentarious in areas of common interest.

3) The development of an integrated collaborative National Animal Health Strategy

In the fall of 2004, the Government of Canada announced its intent to develop an integrated and collaborative national animal health strategy in order to address the convergence of a number of drivers including zoonotic and public health risks, environmental sustainability and ecosystem management, changing societal values, food and security and the economic opportunities and viability of the live animal production sector. The elaboration of the strategy is intended to be an inclusive and transparent process and to include the conducting of an animal health infrastructure assessment in accordance with the performance, vision and strategy for veterinary services tool developed by the OIE in order to guide future investments.

4) The creation of the Public Health Agency of Canada (PHAC)

In response to severe acute respiratory syndrome (SARS), West Nile virus, avian influenza and other public health threats, the Government of Canada announced in the spring of 2004, the creation of the Public Health Agency of Canada. The PHAC will consolidate and integrate current surveillance systems within Canada to provide for improved real time analysis and mapping of disease occurrence, monitor international movement of human diseases and pathways and direct emergency response activities. The appointment of the Chief Public Health Officer of Canada also provides the opportunity for increased interface and cooperation with the Office of the Chief Veterinary Officer of Canada in the management of zoonotic disease threats and the potential to align surveillance efforts along the wildlife-domestic animal-human continuum.

5) Chronic Wasting Disease (CWD) Technical Working Group and the National Wildlife Disease Strategy

Officials from the Western College of Veterinary Medicine, federal and provincial wildlife, as well as the agriculture agencies, have formed a CWD Technical Working Group and drafted a National CWD Control Strategy. The goal of the strategy is to prevent the spread of CWD in wildlife to new geographic areas or to new species, and ultimately, to eradicate the disease. The strategy will not replace, but will complement existing policies and programs and will provide a framework for coordination among the organizations involved. As mandated by the federal-provincial-territorial Wildlife Ministers Council in September 2004, the CWD Control Strategy is a direct application of the National Wildlife Disease Strategy applied to a specific disease issue and created under the leadership of the Canadian Wildlife Directors Committee.

6) Highly Pathogenic Avian Influenza (HPAI)

The year 2004, was marked by the occurrence of the first outbreak of HPAI in the commercial poultry sector in an area of the Fraser Valley, in the western province of British Columbia. Aspects of the chronology of the outbreak, its resolution and recovery, as well as articles offering insight into the outbreak experience are described in the CAHNet Bulletin, Winter 2004, Edition 9 Special Edition: Avian Influenza (pp1-52).

Two reports, lessons learned and "questions and answers" are posted at :

Lessons Learned Review: The CFIA's Response to the 2004 Avian Influenza Outbreak in B.C.

Questions and Answers CFIA Epidemiological Reports Avian Influenza Outbreak of 2004

Several research projects using data derived from the outbreak, are in progress. On-farm, in-barn first stage composting of poultry was successfully demonstrated during the outbreak and work in this area continues. It is deemed an environmentally sound biocontainment measure for infectious disease control.

The outbreak occurred in the midst of ongoing infrastructure developments in animal agriculture in Canada. Key elements in the disease control strategy include: zoning, animal identification (Canadian Livestock Identification Agency) and traceability , demographics and mapping (GIS/GPS), biosecurity, biocontainment including composting research. Canada continues to develop its FADERS plan (Foreign Animal Disease Emergency Response Strategy) applying first hand lessons, notably the need to integrate multiple first responders (and others as an outbreak expands) in the corresponding levels of local (municipal/county), regional (district/territory), provincial and national governments and industries, in an outbreak. The adoption of an incident command system is planned as an enhancement. The endemic HPAI in Asia and the ongoing threat of a pandemic has raised awareness of the need for an animal and public health plan.

II. Comments on specific List A diseases

Precautions at the border (Qf) include inspection prior to export and upon arrival in Canada and may also include quarantine, certification of country or premises freedom or animal testing, for specific diseases of concern for the species being imported.

A150 Highly Pathogenic Avian Influenza (HPAI)

Low pathogenicity avian influenza (H7) was first detected on February 19, 2004 on a commercial chicken breeder farm in British Columbia’s Fraser Valley. The farm was immediately quarantined and all birds were depopulated. HPAI was detected on the same farm on March 8, 2004. Surveillance activities detected HPAI virus on a second commercial operation, approximately three kilometres from the first, on March 11, 2004.

During the span of the outbreak, 42 commercial and 11 backyard premises were declared infected with HPAI. Most of these premises were concentrated in one of three clusters of infection.

The farm-to-farm movement of people, equipment or birds likely spread the virus over long distances, but once the virus was introduced into a densely populated region, airborne transmission through dust or feathers may have infected nearby flocks.

To contain disease spread, the Government of Canada established movement restrictions and disinfection checkpoints, and took legal steps to require bird owners to prevent unauthorized access to their property. As well, the Government initiated a targeted depopulation program that focussed on rapidly isolating, containing and eliminating detected cases of avian influenza. Susceptible birds present within three kilometres of infected premises were also depopulated, given the contagious nature of the virus.

Depopulation activities were officially suspended on June 4, that is 21 days after depopulation of the last infected flock. All premises where HPAI had been detected, were thoroughly cleaned and disinfected. Surveillance was continued until August 18, 2004 when the control area established in British Columbia's Fraser Valley, was eliminated.

III. Comments on specific List B diseases

Reportable Diseases

In addition to the 15 List A diseases, the following List B diseases are prescribed as Reportable in Canada: anaplasmosis, anthrax, bovine brucellosis (B. abortus), bovine spongiform encephalopathy, bovine tuberculosis (M. bovis), chronic wasting disease, contagious equine metritis, cysticercosis (C. bovis), equine infectious anaemia, equine piroplasmosis (B. equi, B. caballi), fowl typhoid (Salmonella gallinarum), pseudorabies (Aujeszky's disease), pullorum disease (S. pullorum), rabies, scrapie, trichinellosis and Venezuelan equine encephalomyelitis. Many of these diseases have never been reported in Canada, or have been eradicated.

The following reportable List B diseases were the focus of disease control and or surveillance activities in farmed livestock in 2004:

1. B051 Anthrax

In 2004, the disease was diagnosed on one livestock premises in the province of Saskatchewan. Confirmed laboratory and field diagnoses included nine (9) bovines. The infected premises was placed under federal quarantine and indemnity paid to the owner for anthrax confirmed, dead animals. Infected carcasses were controlled by burning and deep burial while remaining animals in the herd were vaccinated. No cases of anthrax were reported in Canadian wildlife in 2004.

2. B103 Bovine brucellosis (Brucella abortus)

In 2004, Canada remained free of bovine brucellosis. No cases of the disease have been identified in livestock in Canada since 1988 (farmed bison) and 1989 (cattle). The disease has never been reported in farmed cervidae in Canada. Vaccination for brucellosis has not been practised in Canada since April 2000.

Routine serological testing of market and slaughter cattle and routine milk ring testing of dairy cattle was discontinued in 1999. However, auction market testing of cattle and farmed bison 24 months and older continues in five markets in northern Alberta and British Columbia, in response to the presence of the disease in free-roaming bison herds in and around Wood Buffalo National Park. A statistically-based national bovine serum survey was conducted in 2002-2003. Of 15,105 samples screened using the fluorescent polarization assay, 24 samples were found to be positive. These 24 samples underwent confirmatory testing using a cELISA and all were found to be negative. These results demonstrate that the Canadian cattle population remains free of bovine brucellosis at or above a prevalence of 0.02% (2/10,000) with 95% confidence.

In 2004, 32,125 cattle, farmed bison and farmed cervidae were tested for brucellosis in conjunction with modified market and slaughter testing (24,707), export and artificial insemination centre testing (6,112), investigatory testing (638),and for other reasons (668). Fourteen suspect animals (5 cattle, 2 farmed bison, and 7 farmed cervidae) were detected and investigated with negative results.

3. B252 Porcine brucellosis (Brucella suis)

In 2004, Canada remained free of porcine brucellosis. B. suis has never been identified in Canadian swine.

A statistically-based national swine serum survey was conducted in 2001-2002. Approximately 16,000 samples from slaughter sows and boars were tested with negative results to demonstrate that the Canadian swine population remains free of porcine brucellosis at or above a prevalence of 0.02% (2/10,000) with 95% confidence.

B. suisIV occurs in Rangifer species (caribou and reindeer) in the Canadian Arctic. Movement controls within the country prevent these animals from entering the livestock producing areas of Canada.

4. B105 Bovine tuberculosis (Mycobacterium bovis)

Canada continues to near the complete eradication of bovine tuberculosis from cattle, farmed bison, and farmed cervidae. One case of M. bovis infection was identified in Canada in 2004 in a dairy cattle herd located in the province of Manitoba. All susceptible species on the infected premises and all animals traced from the infected herd were destroyed and examined, with no evidence of disease spread found. Molecular characterization of the isolate and the findings of the epidemiological investigation indicated the source of the infection was diseased wild cervidae in and around Riding Mountain National Park in Manitoba.

Surveillance for bovine tuberculosis in livestock is based on the routine post mortem inspection of animals at slaughter and the submission of granulomatous lesions for laboratory examination. In 2004, 473,120 mature cattle 21,150 bison and 2,951 elk were inspected at slaughter in Canada, resulting in the submission of 481 granulomatous lesions to the laboratory, which led to the confirmation of bovine tuberculosis in a single dairy cow from a herd in Manitoba.

The slaughter monitoring program is augmented by targeted on-farm tuberculin testing of cattle and farmed bison and the routine on-farm testing of farmed cervid herds. Targeted on-farm testing of cattle and farmed bison is conducted in a special eradication area established around Riding Mountain National Park, where 29 infected wild cervids have been found since 1997. The area encompasses approximately 55,000 breeding animals on 650 premises, representing approximately 10% of Manitoba’s cattle herds and 1% of Canadian cattle herds. In 2004 in Canada, 42,864 cattle were tuberculin tested in relation to the investigation of suspect disease (5,382), targeted area testing (32,798), export and artificial insemination centre testing (4,386), or for other reasons (298). In 2004, 3,574 farmed bison and 26,709 farmed cervidae were also tuberculin tested in Canada.

All regions of Canada are officially free from bovine tuberculosis except the special eradication area around Riding Mountain National Park in Manitoba, which is classified as tuberculosis-accredited-advanced, indicating a very low prevalence of infection.

Bovine tuberculosis is present in free-roaming bison herds in and around Wood Buffalo National Park in northern Canada and free-roaming elk and deer in and around Riding Mountain National Park in Manitoba. Information on these occurrences is found in Canada's report to the OIE Wildlife Diseases Working Group (2004). The diseased wild bison in the Wood Buffalo area pose their greatest threat to adjacent disease-free wild bison herds. A bison management plan is in place that includes no-bison buffer zones, the killing of stray bison, and other measures to minimize the risk of disease spread to wild bison or livestock. The infected free-roaming elk and deer in the Riding Mountain area represent a risk of spread of bovine tuberculosis to surrounding livestock. A multi-agency Bovine Tuberculosis Management Program has been implemented to prevent the spread of the disease to livestock and eliminate the infection in the wild cervidae.

5. B115 Bovine Spongiform Encephalopathy (BSE)

BSE was named a compulsory notifiable disease in 1990, and a national BSE surveillance program was implemented in 1992. On December 17, 2004, the surveillance program detected a second case of BSE in Canada, which was subsequently confirmed on January 2nd, 2005 at Canada’s National BSE Reference Laboratory, National Centre for Foreign Animal Diseases, Winnipeg, Manitoba. The subsequent epidemiological investigation confirmed the index case to be an eight year old dairy cow, born in the province of Alberta on 5 October, 1996. Consistent with OIE recommended guidelines the birth cohort and all progeny born within two years of the onset of clinical signs were identified, traced and when found to be alive were quarantined and ordered destroyed for BSE testing. As a result, 9 live cohort animals were destroyed and with subsequent testing, all 9 were reported as negative for BSE. Under federal legislation the owners of animals ordered destroyed are eligible for financial compensation.

The index case was born prior to the implementation of ruminant feeding regulations in 1997.

Canada's National BSE Surveillance program targets high risk adult cattle, consistent with the recommended guidelines of the OIE. In 2004 the program was responsible for the evaluation of 23,550 samples, representative of all regions of the country and reflecting the demographics of the adult cattle population in Canada. Preliminary screening is performed by rapid test technologies within the Transmissible Spongiform Encephalopathy Laboratory Network, and all confirmatory testing is the responsibility of the National BSE Reference Laboratory.

The detection of this second case of BSE by Canada is the third case attributed to the country and is further impetus for the ongoing epidemiological investigation respecting the apparent geographical and temporal clustering of what is believed to be the second indigenous generation of BSE in North America. The common age of expression (average 83 months) suggests an underlying epidemiological situation in contrast to that experienced in the EU and UK, reflecting the considerable mitigation efforts that have been implemented within the feed and food chains.

6. Chronic Wasting Disease (CWD)

Farmed Cervids

• In 2004, there was one case of CWD in a farmed cervid, in Canada. All of the cervids on the infected farm and all trace-outs of cervids from the infected farm were destroyed, tested and were negative. In 2003, there were no (zero) cases of CWD in farmed cervids reported.
• The national control program for CWD was implemented in 2000 and the disease became reportable in 2001. Suspicious cervids are destroyed and tested for CWD. Where an animal has been identified as having CWD, the herd is investigated to determine the entry of CWD into the herd. All cervids exposed to an infected animal in the last 36 months are destroyed, including any that have left the premises. Cervids that have left the premises and were last exposed between 36 and 60 months before are kept under surveillance by federal veterinarians until 60 months after their last exposure.
• In 2004, the mandatory provincial CWD surveillance programs continued in Alberta, Saskatchewan, Manitoba and the Yukon. The programs require all farmed cervids more than 12 months that die or are slaughtered or that are "down, disabled or diseased" be submitted for testing. CWD has been diagnosed in the provinces of Saskatchewan and Alberta in Canada.

Wild Cervids

• Surveillance of free ranging (wild) cervids from hunter shot submissions in the targeted high risk areas continued. A total of 32 positives were detected in 6,650 samples tested from wild cervids in Saskatchewan. The testing of the 2004 wild cervid samples is incomplete as of March 14th, 2005.

CWD testing

• Approximately 14,449 (1 positive) tests and 9,247 (32 positive) tests were performed on farmed and wild cervids, respectively. After extensive preparation, in conjunction with the Canadian Food Inspection Agency Centre of Expertise for CWD, laboratories in the provinces of Ontario, Quebec and Alberta are using the Biorad test for surveillance purposes. The laboratory in the province of Saskatchewan continues to use the immuno-histochemistry test.

7. B108 Enzootic Bovine Leukosis (EBL)

EBL testing is part of the Canadian Artificial Insemination programs (domestic and export). At the end of 2004 there were also 61 cattle herds enrolled in the Canadian Health Accreditation Program for EBL and 59 herds were EBL accredited with a total of 7,342 animals.

8. B205 Equine Infectious Anaemia (EIA)

During 2004, 69 horses were found EIA infected, most of them in the provinces of British Columbia (34) and Alberta (26). Positive horses were also found in two other provinces: Saskatchewan (6) and Manitoba (3). With a few exceptions, all positive animals were ordered destroyed with compensation paid to the owner. A few owners avail themselves of the option to permanently quarantine the reactor in suitable vector-proof facilities. A total of 81,925 serological tests for EIA were performed for routine domestic and international requirements for racing, exhibition, breeding, sale and stabling, as well as in response to suspected or confirmed disease situations. In 2004, the reactor rate was 0.084%, up from 0.07% reported in 2003.

9. B058 Rabies

Canada reported 261 (254 laboratory confirmed and 7 clinically diagnosed) cases of rabies in domestic and wild animals in 2004. This represents a decrease of 1.5% from the 265 rabies cases reported in 2003. The decrease can be attributed to lower numbers of reported cases in foxes (28 in 2003 vs. 14 in 2004) bats (115 in 2003 vs.83 in 2004), and raccoons (16 in 2003 vs. 5 in 2004). However, there was an increase in the number of rabies positive skunks from 76 reported in 2003 to 116 found in 2004.

In 2004, wild animals accounted for approximately 85% of all positive cases (skunks: 44.44%; bats: 31.8%; foxes: 5.36% and raccoons: 1.92%). Among domestic species, rabies was most often found in cattle (8.43%), followed by equines (2.3%), dogs (2.68%) and cats (0.77%).

The majority of rabid animals were submitted by Ontario (114), Manitoba (78) and Saskatchewan (25). No cases of rabies were reported from Nova Scotia, North West, and the Yukon Territories.

Ontario was the only province, in 2004, to report cases (5) of raccoon variant strain of rabies. Since the first incursion of that particular variant of rabies into Ontario in 1999, a total of 195 raccoons have been confirmed rabid by the CFIA laboratory. In 2004, there were no reported human deaths due to rabies in Canada.

10. B106 Cysticercus bovis

A single cow presented for slaughter at federally inspected facility was identified as infected with C. bovis during routine post mortem inspection in September 2004. The infected animal came from a cow-calf operation of 125 cows located in the province of Ontario. Epidemiological investigation established that the most likely source of the infection was the farm’s pasture contaminated with human faeces in the summer of 2004. The farm has been declared an infected place and remains under quarantine. All cattle reaching market weight will be licenced to slaughter at a federally-inspected abattoir where they will be subject to enhanced postmortem inspection. Infested carcasses will be either condemned or frozen to kill the parasites, depending on the parasitic load. The premises will remain under quarantine until such time as the source of infection has been eliminated and there is evidence that the herd is free of the parasite.

11. B062 Trichinellosis

There was no occurrence of trichinellosis in Canadian swine in 2004. Since 1983, there have only been three findings of Trichinella in Canadian swine, the last one was in 1996. In 2004, approximately 22 million pigs were slaughtered and monitored. All animals tested, including farmed wild boars, were negative. Approximately 51, 610 horses slaughtered were tested and found negative using digestion techniques. The testing of 15,579 samples from the 2001-2002 national swine serological survey was completed in 2003. There were no positive results (Indirect ELISA using excretory-secretory antigen in compliance with OIE recommendations).

Non-Reportable Diseases

Non-reportable List B diseases, which have not been known to occur in Canada include: heartwater, screwworm, babesiosis of cattle, theileriasis, trypanosomiasis, contagious caprine pleuropneumonia, Nairobi sheep disease, epizootic lymphangitis of horses, horse pox, Japanese encephalitis of horses, surra, myxomatosis, viral haemorrhagic disease of rabbits and porcine enterovirus encephalomyelitis (formerly Teschen/Talfan disease).

Aquatic Animal Diseases Notifiable to OIE and others of Significant Importance

(a) Pacific Coast:

Culture Fish

Viral Hemorrhagic Septicemia Virus (VHSV) - North American (NA) Strain
VHSV occasionally caused low mortalities on Atlantic salmon farms in 2004.

Infectious Hematopoietic Necrosis Virus (IHNV)
In past years, there have been outbreaks of IHN in marine farms growing Atlantic salmon (Salmo salar), but none were affected by active disease in 2004.

Yersinia ruckeri (causative agent of Enteric Redmouth Disease (ERM))
ERM disease outbreaks occur occasionally in coho (Oncorhynchus kisutch) salmon juveniles reared in enhancement facilities. Occurrences of disease are controlled through oral antibiotic treatment.

Renibacterium salmoninarum (causative agent to Bacterial Kidney Disease (BKD))
BKD outbreaks occur annually in a number of enhancement hatcheries.

Wild Fish

Viral Hemorrhagic Septicemia Virus (VHSV) - North American (NA) Strain
The virus continues to be isolated from wildlife reservoirs (known reservoirs are pilchard (Sardinops sagax) and herring (Clupea pallasii)).

Infectious Hematopoietic Necrosis Virus (IHNV)
The virus can be isolated from most wild sockeye (Oncorhynchus nerka) stocks returning to freshwater. It is also routinely found in surveys of wild and/or enhanced juveniles emerging from the gravel after hatch.

Yersinia ruckeri (causative agent of Enteric Redmouth Disease)
The agent is frequently isolated from wild adult salmon of Oncorhynchus species. when they return to freshwater.

Renibacterium salmoninarum (causative agent to Bacterial Kidney Disease)
Returning adult coho (O. kisutch ) and Chinook (O. tshawytscha) are frequently found to be carriers of Renibacterium salmoninarum.

Shellfish

Mikrocytos mackini
An outbreak of M. mackini in suspended (hanging) oyster culture showing a high prevalence of visible lesions was reported within a known distribution in British Columbia. Mortalities were not evident, however, harvesting was stopped because of product rejection by processors.

Bonamia ostreae
In 2004, B. ostreae were discovered for the first time at one location in British Columbia, Canada in the European flat oyster (Ostrea edulis). Deaths of 3 and 4 year old oysters at this site were associated with a severe algal bloom, but the exact correlation between the deaths and B. ostreae is not clear. Production of the European oyster is less than 1% of the total oyster production in British Columbia. No other species of oyster were affected and no transfer of oysters occurs between the Pacific and Atlantic coasts of Canada.

b) East Coast:

Culture Fish

Infectious Salmon Anaemia Virus (ISAV)
No changes since 2003, however, RT-PCR analysis is revealing both non-pathogenic and pathogenic strains of ISAV.

Infectious Pancreatic Necrosis Virus (IPNV)
This virus is considered as "widespread" throughout the Atlantic zone and continues to be found, generally in the carrier state, in all species of salmonids, in a variety of age classes, but predominantly from facilities with surface water influence. However, no significant mortality problems were reported from those facilities testing positive for IPNV.

Nervous Necrosis Virus
This virus has been isolated from several facilities rearing Atlantic cod (Gadus morhua) throughout the Atlantic zone.

Y. ruckeri (causative agent of Enteric Redmouth disease)
This bacterium continues to be sporadically isolated in salmonid hosts (Atlantic salmon - Salmo salar) from freshwater facilities in the provinces of New Brunswick and Nova Scotia. No significant mortalities were attributed solely to this bacterium.

Renibacterium salmoninarum> (causative agent of Bacterial Kidney Disease)
This bacterium continues to occur at private aquaculture sites in New Brunswick and Nova Scotia and one federal hatchery of Atlantic salmon broodstock in New Brunswick.

Wild Fish

Infectious Salmon Anaemia Virus (ISAV)
The virus was identified in an adult Atlantic salmon, a suspected aquaculture escapee, captured at a New Brunswick fishway.

Infectious pancreatic necrosis Virus (IPNV)
The virus was isolated from healthy brook trout collected in Nova Scotia.

Viral Hemorrhagic Septicemia (VHSV) - North American strain
This virus was isolated from juvenile Striped bass (Morone saxatilis ) found dead in ice auger holes in New Brunswick and also in sea-run Brown trout (Salmo trutta)in Nova Scotia. The laboratory was unable to confirm, in either case, that VHSV was the cause of death.

Renibacterium salmoninarum (causative agent of Bacterial Kidney Disease)
Renibacterium salmoninarum was isolated from clinically infected kidney of an adult Atlantic salmon, a suspected aquaculture escapee, in a New Brunswick river.

Shellfish

MSX disease (Haplosporidium nelsoni)
MSX in the Eastern oyster remains contained within the Bras d’Or Lakes, Cape Breton, Nova Scotia.

SSO disease (Haplosporidium costale)
SSO was detected by PCR in Eastern oysters in Atlantic Canada. Low level infections, confirmed by histology, were found in 2002 and 2003. No infections have yet been associated with pathology.

IV. Comments on other diseases

West Nile Virus (WNV)

WNV was identified for the first time in the Western Hemisphere in the United States of America in 1999. In Canada the first case of WNV was detected through dead wild bird surveillance in 2001. For the last three years, WNV surveillance in Canada has been a collaborative effort, coordinated by Health Canada and now in 2004 by the newly named Public Health Agency of Canada (PHAC), federal, provincial/territorial ministries and agencies as well as key national organizations such as the Canadian Cooperative Wildlife Health Centre (CCWHC). Surveillance for WNV in wild birds was carried out across Canada in 2003 through a multi-agency program coordinated by the Canadian Cooperative Wildlife Health Centre, Health Canada, and all provincial governments.

As of November, 2004 there have been total of 6236 wild birds tested in Canada with 416 confirmed positive for WNV (Quebec,112; Ontario, 250; Manitoba, 16; Saskatchewan, 29 and Alberta, nine). No positive birds were reported from other provinces and territories. The total number of presumptive or confirmed equine cases was 14: four confirmed positive cases in Alberta, nine in Ontario, and one presumed positive horse in Quebec. No deaths were reported.

During the same time period in 2003, there were 446 presumptive and confirmed positive cases in horses across six provinces: Nova Scotia, Quebec, Ontario, Manitoba, Saskatchewan and Alberta. Cases in equine are presumed low as a result of the widespread use of vaccination. In 2004 there have been no reports of West Nile virus infection in other domestic animals.