Heartworm in dogs in Canada in 1988

In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).     

Heartworm in dogs in Canada in 1987

In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).     

Heartworm in dogs in Canada in 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.

     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1986

In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

     

Serological studies on the infection of dogs in Ontario with Borrelia burgdorferi, the etiological agent of Lyme disease

A serological study was undertaken to determine whether dogs in Ontario are being exposed to Borrelia burgdorferi, the etiological agent of Lyme disease. This study consisted of a survey of randomly selected dogs and testing of diagnostic submissions from candidate Lyme disease cases. The survey of 1,095 dogs, bled between January 1988 and August 1989, revealed a total of 65 (5.9%) enzyme-linked immunosorbent assay (ELISA) reactors, of which 22 had immuno-fluorescent antibody assay (IFA) titers ≥1:32. All but one of the IFA-positive and 10 of the ELISA-positive, IFA-negative sera were further tested by western blot. Eight western blot positive and three equivocal reactors were obtained. Three of the eight confirmed reactors had visited areas known to be endemic for Lyme disease, leaving five reactors that might have been infected in previously undocumented areas for B. burgdorferi activity in Ontario. Diagnostic submissions of sera from 223 dogs were received between August 1987 and February 1992. Test results revealed 21 (9.4%) IFA reactors, of which only six had significant titers (≥1:256) and were reactive by an immunodot Borrelia test. All six dogs had travelled to known Lyme endemic areas. Based on results obtained from this study, it seems likely that the agent of Lyme disease is not widespread in Ontario.     

Small animal deworming protocols, client education, and veterinarian perception of zoonotic parasites in western Canada

Questionnaires were mailed to veterinarians in western Canada to determine dog and cat deworming protocols and the association between perceived zoonotic risk and perceived prevalence of endoparasites and deworming protocols. Of the responding veterinarians (545), 13% and 39% recommended deworming protocols consistent with established guidelines for puppies and kittens, respectively. Mixed animal practitioners and high-perceived prevalence of Toxocara cati were associated with increased appropriate kitten deworming (P < 0.01 and P = 0.04, respectively). High-perceived zoonotic concern of Toxocara canis was associated with increased appropriate puppy deworming (P = 0.01). Sixty-eight percent of veterinarians noted an established hospital deworming protocol, although only 78% followed the protocol. Forty-four percent of veterinarians stated they discussed with all clients the zoonotic risk of animal-derived endoparasites, whereas the remainder discussed it only under particular circumstances or not at all. Most small animal deworming protocols recommended in western Canada begin too late to inhibit endoparasite shedding. Increased educational efforts directed at veterinarians are warranted.     

Use of a C6 ELISA test to evaluate the efficacy of a whole-cell bacterin for the prevention of naturally transmitted canine Borrelia burgdorferi infection

A commercially available C6 ELISA kit was used to detect antibodies induced by natural infection with Borrelia burgdorferi in dogs that lived in an area endemic for Lyme disease. Rates of infection were determined both for nonvaccinated dogs and those that had been vaccinated with a whole-cell B. burgdorferi bacterin (Lyme Vax, Fort Dodge Animal Health) before 6 months of age and were boostered annually. Vaccinated dogs had an infection rate of 5% (8 of 163), whereas 64% (25 of 39) of the non-vaccinated dogs were positive for B. burgdorferi antibodies. The preventable fraction, determined by comparing infection rates in unvaccinated and vaccinated dogs, was 92.2% (95% confidence interval: 84.3% to 96.3%). In addition, screening of nonvaccinated dogs at six Connecticut clinics (Middletown, Portland, Essex, Old Lyme, Durham, and Marlborough) with the C6 ELISA test revealed infection rates ranging from 41% to 73%, demonstrating a high level of infected dogs in the area. It was concluded that emphasis should be placed on vaccinating young dogs at risk for Lyme disease before they are exposed to infected ticks. Results of this study support the value of immunization with this whole-cell Lyme disease bacterin for dogs at risk for infection by B. burgdorferi.     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

     

Veterinarians’ perspective on a voluntary Johne’s disease prevention program in Ontario and western Canada

A survey was conducted to assess the beliefs of veterinarians on Johne’s disease (JD) and their attitudes towards the Canadian, risk assessment based, JD prevention program. The veterinarians surveyed believed Mycobacterium avium subsp. paratuberculosis may have zoonotic potential, liked the risk assessment based program, and thought it could lead to the prevention of other on-farm diseases.     

Canine borreliosis.

A guild of organisms carried by the same vector (Ixodes ticks) in Lyme-endemic areas may be confounding the understanding of Lyme disease in dogs. A new diagnostic method, the C6 peptide test for Lyme, and serology and PCR testing for Ehrlichia, Babesia, and Bartonella species will help to sort out seroprevalence and symptomatology caused by exposure to these agents or by coinfections. In addition, Rickettsia, Leptospira, Mycoplasma species, and more could be involved in dogs diagnosed with a "doxycycline-responsive" disease. The author does not recommend treating asymptomatic Borrelia carrier dogs, but does recommend screening them for proteinuria and for exposure to other agents. A positive Lyme titer is a marker of exposure to Ixodes ticks and the agents they carry. The risk/benefit of vaccination will be understood better as the symptomatology and immunopathogenesis of Lyme disease are defined. Meanwhile, tick control is highly recommended for all dogs in Lyme-endemic areas.     

Tick-borne zoonoses: Lyme disease, ehrlichiosis, and Rocky Mountain spotted fever

The primary health risk for veterinary staff and companion pet owners is exposure to ticks in the wooded/pasture areas or to ticks brought indoors by their pets. There are no proven cases of direct animal to human transmission for Lyme disease, ehrlichiosis, or Rocky Mountain spotted fever. Direct inoculation of blood from a bacteremic animal, eg, by needle stick is a theoretical, but, so far, undocumented health risk. However, veterinarians should record needle sticks or other inoculation-type injuries that occur in their practices. Prevention of Lyme disease, ehrlichiosis, Rocky Mountain spotted fever, and other tick-borne diseases depends on the avoidance of tick-infested areas and proper use of repellents and acaricides.     

Evaluation of risk factors for Cryptococcus gattii infection in dogs and cats

OBJECTIVE: To determine risk factors associated with Cryptococcus gattii infection in dogs and cats residing on Vancouver Island in British Columbia, Canada. DESIGN: Matched case-control study. ANIMALS: 20 dogs and 29 cats with C gattii infection and matched controls. PROCEDURE: Dogs and cats with a confirmed or probable diagnosis of cryptococcosis resulting from infection with C gattii were enrolled by veterinarians, and owners completed a questionnaire designed to obtain information pertaining to potential risk factors for the disease. Owners of matched control animals were also interviewed. Odds ratios and 95% confidence intervals or paired t tests were calculated to determine significant associations. RESULTS: Animals were enrolled during 2 noncontiguous periods in August 2001 to February 2002 (8 dogs and 9 cats enrolled) and May to December 2003 (12 dogs and 20 cats enrolled). Risk factors significantly associated with development of cryptococcosis included residing within 10 km of a logging site or other area of commercial soil disturbance, above-average level of activity of the animal, travelling of the animal on Vancouver Island, hunting by the animal, and owners hiking or visiting a botanic garden. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that dogs and cats that were active or that lived near a site of commercial environmental disturbance had a significantly increased risk of developing C gattii infection. Veterinarians should communicate these risks to owners in context because cryptococcosis was an uncommon disease in this population.     

Serodiagnosis of Lyme disease in UK dogs

Lyme disease is a chronic, multisystemic, inflammatory disorder of man and animals associated with infection by the tick-borne spirochaete, Borrelia burgdorferi. Lyme disease was recently reported for the first time in a dog in the UK (May and others 1990). Using an enzyme-linked immunosorbent assay (ELISA), we have performed a serological survey to investigate the prevalence of antibodies to B burgdorferi in UK dogs. The survey has shown that dogs from many areas in the UK have serum antibodies to B burgdorferi, that the presence of serum antibodies is associated with known exposure to ticks and that some dogs seropositive for B burgdorferi have clinical signs consistent with Lyme disease. High levels of serum anti-Borrelia antibodies are not diagnostic for canine Lyme disease, but, in association with appropriate clinical signs, they help to confirm the diagnosis in suspected cases.     

Canines as sentinels for Lyme disease in San Diego County, California.

Prevalence of Lyme borreliosis in canine sentinels has been shown to correlate with infection in humans. One thousand canine sera (917 dogs, 83 coyotes) obtained from animal control authorities and area veterinarians were screened by ELISA for antibodies to Borrelia burgdorferi. Results were validated by Western blot and indirect fluorescent antibody (IFA) tests at referee laboratories. Criterion for a positive Western blot was presence of 5 of 10 of the most common antigen IgG bands; for IFA, >1:128 or the equivalent when correcting for interlaboratory variability. Twenty-two of 1,000 canines were confirmed serologically positive (21 dogs and 1 coyote; seroprevalence 2.3% and 1.2%, respectively). Lifestyle, breed size, gender, and age were not statistically predictive of seropositive status. No regional clustering of seropositive animals was detected. The low prevalence of seropositivity in sentinel canines suggests the Lyme borreliosis hazard in San Diego County is minimal.     

Chemoprophylaxis and treatment of African canine trypanosomosis in French military working dogs: A retrospective study

African trypanosomosis is a major threat to livestock production in sub-Saharan Africa. Although the disease mainly concerns cattle, dogs can also be infected by Trypanosoma spp. transmitted by tsetse flies. Between 1997 and 2003, the parasite Trypanosoma congolense was identified in French military dogs sent to Africa. On infected dogs, the diagnosis was made during the mission or just after the return to France, depending on when the symptoms appeared. The high incidence and mortality rate among these dogs led veterinarians of the French Health Service to implement a systematic chemoprophylaxis beginning in 2004. Between 2004 and 2011, the chemoprophylaxis was carried out on more than 400 military dogs. The protocol of chemoprophylaxis relies on the use of isometamidium chloride (Trypamidium^®, Merial). The drug has been used successfully at the dosage of 1 mg/kg body weight by deep intramuscular injection, every two or three months. In addition, dogs are given collars impregnated with deltamethrin (Scalibor^®, MSD Animal Health). Isometamidium chloride was also used successfully in the treatment of military dogs infected with T. congolense, with a full recovery and without any relapses.     

Seroprevalence against Borrelia burgdorferi sensu lato and occurence of antibody co-expression with Anaplasma phagocytophilum in dogs in Latvia

Background

Lyme disease is commonly diagnosed in humans in Latvia, but up to date no studies have been performed to investigate its prevalence in dogs. The aim of this study was to evaluate if seroprevalence against B. burgdorferi sensu lato (B. burgdorferi s.l.) and co-expression of antibodies against B.burgdorferi s.l. and A. phagocytophilum is higher in dogs with clinical suspicion of tick-borne diseases compared to healthy dogs.

Findings

Venous blood was taken from healthy dogs (n=441) and dogs suspected to have borreliosis and/ or canine granulocytic anaplasmosis (n=29). The presence of antibodies was detected with SNAP 4Dx test (IDEXX, Westbrook, Maine, USA). The seroprevalence against B. burgdorferi s.l. in healthy dogs was 2.49% (11/441) and 36% (4/11) of seropositive dogs had antibodies against both of investigated bacteria. None of the dogs in sick dog group had detectable antibodies against B. burgdorferi s.l.

Conclusions

We conclude that seroprevalence to B. burgdorferi s.l. in dogs in Latvia is low and that dogs with suspicion of tick-borne disease do not have higher B. burgdorferi s.l. seroprevalence than healthy dogs. Dogs that express antibodies against B. burgdorferi s.l. frequently co-express antibodies against A. phagocytophilum.     

Comparison of two immunochromatographic assays and the indirect immunofluorscence antibody test for diagnosis of Trypanosoma cruzi infection in dogs in south central Louisiana

Two rapid tests evaluated in dogs considered to be of high risk of infection with the Chagas parasite Trypanosoma cruzi using two immunochromatographic assays: Trypanosoma Detect™ for canine, InBios, Seattle, WA and CHAGAS STAT-PAK™ assay, Chembio Diagnostic Systems, Medford, NY, in south central Louisiana. For this purpose a serological survey was carried out in a total of 122 dogs and a serum bank was created. These 122 animals were first tested by IFAT that was used as the standard test. From the serum bank 50 samples were tested using the two rapid Chagas assays and results compared to the standard test IFAT. The serological survey using IFAT showed a prevalence of T. cruzi infection in 22.1% of the tested dogs. In the immunochromatographic assays, 13 and 11 animals were positive on rapid assay: Trypanosoma Detect™ for canine, InBios and CHAGAS STAT-PAK™, Chembio Diagnostic Systems, respectively compared to 11 positive by IFAT. These two immunochromatographic tests have shown high susceptibility and specificity compared to our standard method IFAT. The rapid, easy and accurate screening assays used in conjunction with confirmatory tests, would be an excellent tool for veterinarians to diagnose T. cruzi infection. Early detection of T. cruzi infection may prevent complications through an effective treatment. Greater awareness by veterinarians of the risk, clinical findings, history along with diagnostic methods will contribute greatly to an understanding of the true prevalence of Chagas disease in dogs in Louisiana.