SEPTEMBER 2012 THE RIDER/ 5 Disease Advisory: West Nile Virus
West Nile Virus (WNV) is endemic in Ontario and cases occur in the horse popu- lation at varying levels each year. There is the potential for a significant increase in the number of equine WNV cases in Ontario in 2012. Public Health Ontario has reported the highest number of WNV-posi- tive mosquito pools since 2002, which is the first year that human and equine cases were identified in Ontario. As of August 22, 2012, there have been 49 confirmed or probable cases of human WNV in the province. At this time, there are no reports of equine cases. However, it seems inevitable that there will be some. The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) requests that the veterinary community consider WNV in horses with neurological signs, and assist in identifying positive cases through appropriate testing. WNV is an immediately notifiable disease under the federal Health of Animals Act. Signs of WNV (such as lethargy, ataxia, facial tremors and limb paralysis) can mimic a variety of encephalitides including rabies, Eastern Equine Encephalitis (EEE), West- ern Equine Encephalitis (WEE), botulism, hepatic
encephalopathy, equine protozoal myeloen- cephalitis (EPM), tetanus, equine herpes virus 1 (EHV-1), lead poisoning, and wob- blers syndrome. Mortality rates amongst horses showing clinical signs of WNV are approximately 35%.
WNV infections have been reported in a wide range of animal and bird species, including horses, dogs, cats, deer, crows, chickens, geese, jays, rap- tors and owls. Horses and birds of the corvid family, including ravens, mag- pies, jays and crows, are particularly susceptible to WNV. Positive equine cases of WNV in Ontario, when identified, will be fol- lowed up by the local public health unit to determine whether the exposure of the horse was local or travel-related, and the vaccination status of the horse. The public health unit will also ensure that human exposure to mosquitoes in the area which may potentially be carrying WNV is minimized. Depending on the time of year, the owners of properties on which a positive equine WNV case is diagnosed may be asked to allow public health mosquito traps to be placed around their property for surveillance purposes – there is no cost to the property owner for this.
Information on WNV prevention and control can be found at:
www.aaep.org/pdfs/control_guidelines/West%20Nile%20Virus.pdf Surveillance data for equine neurological diseases in Ontario can be found at:
www.omafra.gov.on.ca/english/livestock/horses/westnile.htm#surveillance Questions with respect to veterinary public health issues or responses in Ontario should be directed to:
Dr. Catherine Filejski, Public Health Veterinarian
Ontario Ministry of Health and Long-Term Care Tel. (416) 212-0424 Blackberry: (416) 427-7944
catherine.filejski@
ontario.ca
Effective equine vaccines for WNV are available and veterinarians should ensure that vaccinations are up-to-date in their clients’ animals. There is no vaccine for humans and no treatment, other than supportive, once a per- son is infected.
Questions with respect to animal health issues or responses in Ontario should be directed to:
Dr. Janet Alsop
Lead Veterinarian – Regulatory Response Ontario Ministry of Agriculture, Food and Rural Affairs Tel. (519) 826-4323
janet.alsop@
ontario.ca
Most equine cases of WNV occur between August and September, although cases can occur into October if environ- mental conditions permit the survival of the mosquito vector species.
Ontario’s local public health units are currently conducting mosquito surveil- lance. Birds are the natural host for the virus, which is transmitted to horses and humans by mosquitoes which have bitten an infected bird. As of August 22, 2012, there have been 312 WNV-positive mosquito pools identified in 25 health units across the province (
http://www.oahpp.ca/resources/vector- borne-disease-surveillance-
reports.html#WNV). This number is almost as high as those identified in 2002, when there were 101 confirmed cases of equine WNV in Ontario.
LongRun Fundraiser Clinics
LongRun Retirement will be hosting two clinics this fall, with hopefully more to come!
The first clinic on October 20th, from 10 am to 2 pm is called “From Teeth to Tail – A look at whole horse healthcare”. Featured speakers include Catherine Mar- tin, RVT – Merck Animal Health and Dr. Laurie Dykeman of Paris Equine Services. Planned topics include “Equine Vaccina- tion Updates”, “To Deworm or Not to Deworm” plus “Equine Dentistry”. The cost is a $10 tax receipted donation to Lon- gRun.
The second clinic will be “Retraining your OTTB”. The date in November will be announced soon. You will find more details as they become available and can sign up for the clinics at www.longrunre-
tirement.com.
Through fundraising, volunteer work and with assistance from the Ontario thor- oughbred industry, LongRun’s mandate is the care of retired racehorses. They evalu- ate each animal and give them individual care, fostering them until they can be placed in a permanent, loving home. Funds raised are also used for transportation, feed, basic re-training, farrier and medical expenses, as well as blankets and halters. Currently, LongRun does not have a per- manent facility and relies on temporary fos- ter homes but are saving towards having their own LongRun facility.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64