Rabies Report

Document Sample
Rabies Report Powered By Docstoc
					                                                                                                                         Rabies Report 2000

 Summary                                                                                        Testing
 Rabies virus is widespread in the skunk population of Manitoba,                                The Canadian Food Inspection Agency Laboratory in Lethbridge
 in Arctic Fox and occasionally seen in bats. Skunk rabies                                      tests rabies suspects. Arrangements for sample pickup and testing
 incidence fluctuates over time. Rabies prevalence has been high                                can be made through your district veterinarian. The test is done on
 for the past three years. When skunk rabies is high there is                                   the brain tissue of dead animals. If people have been exposed to
 increased spill over into the domestic animal population and risk                              the suspect animal, results are usually available within 24 hours.
 to people.
                                                                                                                Canadian Food Inspection Agency
 The Disease                                                                                                       District Offices In Manitoba
 Rabies is a viral brain disease of all mammals, with strains of the
 virus having adapted to host species. In Manitoba, the primary                                        Winnipeg City                        983-2219
 reservoir for the virus the skunk. When other animals die of                                         Portage La Prairie                    857-4171
 rabies in Manitoba it is usually skunk strain rabies. Domestic                                           Carman                            745-2292
 animals are exposed by contact with infected wild animals.                                         Minnedosa-Brandon                       726-7552
 Humans can contract rabies from wildlife or domestic animals                                       Brandon-Boissevain                      726-7556
 but statistically bats are the greatest risk. In Canada there have                                       Dauphin                           638-3322
 been 22 reported human deaths from rabies since 1924, none
 originated in Manitoba.                                                                        Indemnity Program
                                                                                                In Manitoba, farmers may recover part or all of the value of most
 The rabies virus is spread by contact with saliva from an infected                             domestic farm animals diagnosed with rabies. The program has
 animal, usually through bites or scratches, abrasions, or open                                 been operating for many years and encourages the reporting of
 wounds in the skin. Domestic animals may become exposed                                        suspected animals. The program pays up to $1000.00 for cattle
 during normal grazing or roaming. Occasionally, rabid wild                                     and $500.00 for horses. The funding for the program is 60% from
 animals will enter barns, paddocks, and lots. Livestock are often                              Manitoba Agriculture and Food and 40% from the Canadian Food
 exposed when they investigate this new animal in their                                         Inspection Agency. In 2000, $22,062.50 was paid out to Manitoba
 surroundings.                                                                                  producers under the rabies indemnity program.

 Rabies is a fatal disease. If infection occurs, human deaths can                               To qualify for indemnity, the animal must have died from rabies.
 be avoided by post exposure prophylaxis. The rabies virus is not                               Normally the CFIA laboratory report is used as confirmation. The
 easily transmitted. If you must handle a suspect animal, barrier                               claim is initiated at the CFIA district office and the Province of
 protection (rubber cloves) and normal sanitation will decrease                                 Manitoba issues the payment in six to eight weeks.
 risk of human exposure. Eye protection should also be used, as
 the virus can pass through the conjunctiva.
                                                                                                                     Rabies In Manitoba 1993-2000

                                                                                                            1993 1994 1995 1996 1997            1998    1999       2000
                                                                                                Skunk         34 63 28      18   45              139     183        197
                                                                                                Bovine         8   7    2    1    2               17      20         19
                                                                                                Horse          3   2    0    2    1                1       3          4
                                                                                                Dog/cat        2   3    2    1    4               11       8         12
                                                                                                Wildlife       0   1    3    1    4                4       4          2
                                                                                                Bat            0   3    2    1    2                1       2          1

                                                                                                Number of rabies cases in Manitoba per year 1993-2000 for major species
                                                                                                affected. Domestic animals die from the “skunk strain” of rabies. Risk for
                                                                                                spillover increases with the prevalence in the skunk population. Rabies in
                                                                                                  bats is a separate strain and occurs independently of rabies in skunks.

Figure 1 Rabies Virus particles are quite large for                                                      Manitoba 2000 - Rabies Positive By Month
viruses 180 x 70nm. Bovine Virus Diarrhea of cattle is                                         45
about 40-60nm in diameter. The Rhabdovirus family                                                                                               Skunk       Other
has a unique bullet-shaped appearance. They are
                                                                       Total Number of Cases

enveloped with prominent spikes on the surface. The                                            35
envelope is lined by the matrix protein and contains the                                       30
nucleocapsid (RNA + N protein) wound helically inside
the core. As with most enveloped viruses, the particle                                         25
is relatively fragile outside the host.                                                        20
                                  Figure 2
                                  Rabies Positive By Month
                                  67% (158/235) cases of                                       5
                                  rabies in Manitoba in 2000                                   0
                                  occurred in the first six
                                                                                                     J     F   M     A     M    J   J       A     S     O      N     D
                                  months of the year.
Rabies in Manitoba                                                                   If bitten by a wild or suspect animal
Manitoba is an area with wildlife persistently infected with rabies. The             1] Immediate and extensive washing of all bite
primary reservoir species is the skunk. Annual rate of infection in domestic         wounds, scratches, or other sites of potential exposure
animals closely parallels the number of positive skunk identified in any             for 10 minutes with soap and water is arguably the
particular year. It is an offence under the Diseases and Dead Bodies                 most important measure for preventing rabies
Regulation, made underThe Public Health Act, for anyone other than a                 following an exposure to a rabid animal. Experiments
medical or veterinary research facility, a game farm or a zoological garden,         done in animals suggest that thorough and vigorous
to keep a skunk.                                                                     cleansing to the depth of the wound with a 20% soap
                                                                                     solution can reduce the risk of developing rabies by up
In Manitoba rabies follows a long-term time line with upswings in skunk              to 90%.
rabies seen every six or seven years. The past three years had the highest           2] If possible, retain the animal for laboratory
incidents of rabies in wildlife for the past decade. Rabies in skunks was            investigation. Brain tissue is required so please, do not
previously concentrated in the Interlake and the southwest corner of the             shoot animal in head.
province, but is now widely dispersed.                                               3] Call your Doctor and local public health unit to
                                                                                     report the incident.
There are precautions everyone can take to avoid possible exposure to rabies.
• Vaccinate your pets. The cases that usually present the highest numbers of human exposures involve rabid domestic animals. In North
America the most common domestic animal to contract rabies is the cat.
• Do not let pets roam free. Humans are frequently exposed to rabies through handling a pet, which has fought with a rabid animal. If any
saliva from the rabid animal is left on a pet's fur, there is a risk of exposure.
• Avoid any contact with wild animals, alive or dead. The behavior of rabid animals is unpredictable. Approaching a sick animal, no matter
what condition it appears to be in, is dangerous. The rabies virus can be active after the host animal dies, but it can only be transmitted if
there is direct contact. If you must handle wildlife, wear gloves or use a shovel.
• High risk employment groups such as people working the veterinary field, animal shelters, wildlife rehabilitation, and trappers should
receive pre-exposure immunization. In Winnipeg, contact Margaret Rubin (St. Boniface Hospital 237-2927; Health Sciences Centre 789-
3364). Outside of Winnipeg, contact your physician or local public health unit.

                                                                                Raccoon Rabies
                                                                                The raccoon adapted strain of rabies was first reported in
                                                                                Florida in the 1940’s. The strain was trans-located to
                                                                                Virginia in hunting dogs in 1977. Since the start of the mid-
                                                                                Atlantic epizootic, the front has progressed north and west
                                                                                at approximately 18-24 miles each year (Figure 3).

                                                                                On July 14, 1999, the first case of rabies caused by the
                                                                                raccoon-associated variant was diagnosed in a raccoon
                                                                                north of the St. Lawrence River, near Prescott, Ontario. A
                                                                                second case was identified on July 26, 9 miles west of the
                                                                                first case. A third case was diagnosed on September 17,
                                                                                approximately 9 miles north of the other two cases.

                                                                                The Ontario Ministry of Natural Resources has been
                                                                                conducting trap-vaccinate-release programs for several
                                                                                years at the major border crossings in the St. Lawrence and
                                                                                Niagara areas to build defensive zones of vaccinated
                                                                                raccoons to minimize the spread of epizootic rabies. These
                                                                                first cases occurred outside the vaccinated zone. A total of
                                                                                880 raccoons, 220 striped skunks, and one red fox,
                                                                                captured within a 3-mile radius of each of the first two
                                                                                cases, were negative for rabies by immuno-fluorescence

                                                                                The single Manitoba raccoon in 2000 with rabies (north of
                                                                                Brandon) died of skunk strain rabies.

   One of the primary concerns if a person has contact with a bat is the possibility of exposure to rabies. Bats have been increasingly
   implicated as wildlife reservoirs for variants of rabies virus that have been transmitted to humans. Since 1980, 22 of 25
   indigenously acquired human rabies cases in the United States have been attributable to bat strains of rabies virus. Bat bites are
   not always visible; therefore, any close human contact with a bat needs to be carefully evaluated for the need for prophylaxis.

   Additionally, in situations in which a bat is physically present and the person cannot exclude the possibility of a bite (e.g. if the
   person was sleeping), postexposure treatment should be considered unless prompt testing of the bat has ruled out rabies infection.
   It is especially important to educate children about avoiding contact with bats. Down bats may be clinically affected with rabies and
   shedding virus at a very high concentration in saliva. Bats are also have social grooming behaviour and bat fur may carry a high
   level of rabies virus. When a bat is found in a room where people (children) have been sleeping, medical advice should be sought
   immediately. Where possible, the bat should be safely captured and the CFIA District Veterinarian notified so the specimen can be
   tested for rabies.
Human Rabies In Canada 2000
On October 6tth 2000, a 9-year-old boy in Montreal, with no history of travel outside of Quebec died from rabies encephalitis caused by a
variant associated with insectivorous bats. Since 1970 five people in Canada have died of rabies, one contracted dog rabies in the
Dominican Republic and the other four, infected within Canada, were confirmed as bat strain rabies. Bats should be prevented from
entering living spaces and contact with people and pets.

                        61                                                          Skunk (197)
                                                                                    Dog (5) + 2 in Churchill
                                                                                    Cat (5)
                                                                                    Bovine (19)
                                                                                    Equine (4)

      67                               28

 91            42                                                        49
                             36         31                                           3
           11                                                                                                                                            8
 90                                                                                                       94
                                                                              88                                         27

                              80                                               53
 82            95                                                                                                                                            3
                                                   67                                                                                          6             2
                                                                                     33                                            17
                                        100                     16                                                                                                                         2
 25                                                                      79
                9                                   40                                                                              87
                                  92                            56                  48        110    46
                                                                                                                                                                            85            45
                                  38                                                                                                                77            83
  4                  54                             89                                                                             116                                             13
                                                               66              47
 109                      117                                                                                                                   81
                                              19          26                             62                                                                       *
                                                                                                63                                        15                                       98
                                             112                                                                                                                             104
           70                 93                                                                                          37                                 74                    84
                                                               64              96             107
                                                   34                                                     97                                   52                                         72
                                                                                                                    22                                                 39
           1                      14               114                   101                                        1                                                              44
                                                                75                              50                  0              78
                                                                                         5                          5                                        21
      24                                                                                                                                 73                                         102
                    7         12                                                                                                                    57
                                       115         59           106                76               51         68             99                                   30

 Figure 4 Rabies Positive Samples by Species and Regional Municipality Small numbers refer to Municipality as identified on the
 Key Table on page 4. Animals positive and not identified on map include 8 skunks within Winnipeg City limits, 1 bat in Winnipeg, 1
 Raccoon from Elton RM, 1 coyote from Stuartburn and 2 dogs from Churchill. Data was provided by Olga Anderson and Dr. Blaine
 Thompson Canadian Food Inspection Agency, Winnipeg.
 Manitoba Rural Municipalities Rabies Positive Jan-Dec 2000 Key to Figure 4 (Positive Species#)
 1 Albert                     28 Ethelbert             55 Minitonas               82 Russel (S1)                       109 Wallace (B1 S4)
 2 LGD Alexander (S2)         29 LGD Fisher (E1S3)     56 Minto (B1)              83 St. Andrews                       110 Westbourne
 3 LGD Alonsa (S 5 C1 F1)     30 Franklin (S1)         57 Montcalm                84 Ste. Anne (S2)                    #   West St. Paul
 4 Archie                     31 Gilbert Plains        58 Morris (S1)             85 St. Clements (F1,S5)              112 Whitehead (B1 S2)
 5 Argyle (S3)                32 Gimli (S2)            59 Morton (S2)             86 St. Francois Xavier (S1)          113 Whitemouth
 6 LGD Armstrong (B2 S9 E1) 33 Glenella (B1)           60 Mossey River (C 1 S 2) 87 St. Laurent (F 1,S 2)              114 Whitewater (S1)
 7 Arthur (S1)                34 Glenwood (B1)         61 LGD Mountain            88 Ste. Rose (S4)                    115 Winchester
 8 Bifrost (B3 S4)            35 LGD Grahamdale (S1) 62 North Cypress (S1)        89 Saskatchewan                      116 Woodlands (F 1 E1 S1)
 9 Birtle (S3)                36 Grandview             63 North Norfolk (B1 S 2) 90 Shellmouth (S1)                    117 Woodworth (S2)
 10 Blanshard (S     1)
                              37 Grey                  64 Oakland                 91 Shell River
 11 Boulton                   38 Hamiota (S 3)         65 Ochre River (S1)        92 Shoal Lake (S 2)                  Positive Species
 12 Brenda (S   1)
                              39 Hanover (S8)          66 Odanah (B1,S6)          93 Sifton (C 1 S 1)                  S = Skunk
 13 Brokenhead (S2)           40 Harrison (S1)         67 LGD Park                94 Siglunes (S12)                    B = Bovine (cattle)
 14 Cameron (S3)              41 Headingley            68 Pembina (C1)            95 Siver Creek (S 1)                 E = Equine (Horse)
 15 Cartier (S1)              42 Hillsburg             69 LGD Piney               96 South Cypress                     C = Canine (dog)
 16 Clanwilliam               43 Kelsey                70 Pipestone (S 1)         97 South Norfolk (S2)                F = Feline (cat)
 17 Coldwell (S   3)
                              44 La Broquerie (S1)     71 Portage la Prairie(S 3) 98 Springfield (S9)
 18 Cornwallis                45 Lac du Bonnet         72 LGD Reynolds            99 Stanley (S 10)                    Not on Map
 19 Daly (B1, S3)             46 Lakeview              73 Rhineland (S4)          100 Strathclair (C1 S1)              Churchill(C 2 )
 20 Dauphin (S3)              47 Langford (B1)         74 Ritchot (S1)            101 Strathcona (B1)                  Winnipeg City (1bat, S8)
 21 De Salaberry (S1)         48 Lansdowne (B1)        75 Riverside (B1 S2)       102 LGD Stuartburn (S4)              Elton 1 Racoon
 22 Dufferin (F 1 S1)         49 Lawrence (S2)         76 Roblin (S3)             103 Swan River                       Stewartburn 1 Coyote
 * East St. Paul (S1)         50 Lorne (B1 S1)         77 Rockwood (S1)           104 Tache
 24 Edward                    51 Louise (S1)           78 Roland                  105 Thompson
 25 Ellice (S2)
                              52 MacDonald (S1)        79 Rosedale                106 Turtle Mountain (B1,S3)
 26 Elton (S3)                53 McCreary (S2)         80 Rossburn (S 3)          107 Victoria
 27 Eriksdale (E1 S2)         54 Miniota (S4)          81 Rosser                  108 Victoria Beach
Other Wild Animals and Risks
Rabies in wild animals exists as variants of the virus adapted to specific species of animal. On the basis of new information regarding
rabies pathogenesis and viral shedding patterns in ferrets, ferrets are now considered in the category with dogs and cats rather than as
wild terrestrial carnivores. In ferrets vaccination prevents disease and the length of shedding to clinical symptoms is known. In Manitoba
agricultural regions the most common rabies variant is mid-west skunk strain. In Churchill the most common variant is the Arctic Fox
strain. Insectivorous bats maintain several specific strains rarely identified in Manitoba. In Manitoba, skunk strain rabies sometimes is
reported in other wildlife such as Coyote (‘00-1), Groundhog (‘94-1, ‘99-1), Fisher (‘97-1, ‘98-1) and Badger (‘98-1). The Arctic Fox strain
is commonly identified in arctic fox in Manitoba (‘95-3, ‘96-1, ‘97-3, ‘98-2, ‘99-2) and occasionally seen in dogs in the Churchill area.

Small rodents (e.g., squirrels, hamsters, guinea pigs, gerbils, chipmunks, rats, and mice) and lagomorphs (including rabbits and hares)
are almost never found to be infected with rabies and have not been known to transmit rabies to humans. From 1990 through 1996, in
areas of the United States where raccoon rabies was enzootic, groundhogs accounted for 93% of the 371 cases of rabies among
rodents reported to Center for Disease Control in Atlanta.

Wild animals and wild animal hybrids should not be kept as pets. Because the period of rabies virus shedding in these animals is
unknown, these animals should be euthanized and tested rather than confined and observed when they bite humans. It is an offence
under The Wildlife Act to posses a wolf-dog hybrid in Manitoba unless so authorized by a permit issued by the Director of Wildlife.

Vaccination Dogs, cats, and ferrets
All dogs, cats, and ferrets should be vaccinated against rabies and revaccinated in accordance with manufacturers label requirements.
If a previously vaccinated animal is overdue for a booster, it should be revaccinated with a single dose of vaccine and placed on an
annual or triennial schedule, depending on the type of vaccine used. Animal rabies vaccine in Canada is available only from a
veterinarian. Your veterinarian can provide additional information on rabies control and prevention in domestic animals. The National
Association of State Public Health Veterinarians, Inc. (United States) publishes a Compendium of Animal Rabies Prevention and Control
every year. The 2000 issue is available at (http://www.cdc.gov/mmwr/preview/mmwrhtml/rr4908a2.htm).
If your pet dog or cat is in contact with a rabies suspect animal contact your local veterinarian or the closest Canadian Food Inspection
Agency District Veterinary Office. Large domestic animals can kill or injure people when affected by rabies. Use caution when horses
and cattle behave abnormally.

Veterinarians in Manitoba are Licensed by:
Manitoba Veterinary Medical Association                                                            For More Information Contact
6014 Roblin Blvd.                                                                                  Terry Whiting
Winnipeg, Manitoba                                                                                 Disease Control, Veterinary Services Branch
R3R 0H4                                                                                            Manitoba Agriculture and Food
                                                                                                   Tel: 204-945-6782
Tel. 204-832-1276                                                                                  Fax:204-945-8062 twhiting@agr.gov.mb.ca
Fax. 204-832-1382
Marcel Fraser, Registrar

                                                                                                                          Printed February 2001

Shared By: