We are currently seeing an increase in rabies cases in our state. For several years we have been told by health officials that we should expect an increase in rabies cases as the virus moves north from Mexico. Since there is a significant health risk to humans, we need to be aware of what is happening. Rabies in humans is close to 100 percent fatal.
The Missouri Department of Health recently released the incidence report for May 2012 reporting 13 positive rabies cases confirmed. This was an increase of five cases compared to the same time last year. Seven cases have been found in skunks and six in bats. Currently in Missouri there are no counties on alert. However, cases have been reported in Boone, Franklin, St. Louis, Reynolds, Laclede, Webster, Douglas, and Howell counties.
Signs can vary as two different forms of the disease are seen: furious and dumb.
Animals with the furious form usually behave abnormally. They may hide and become very restless. They do become very aggressive, biting objects and people. Salivation follows due to paralysis of the throat. The bark also will sound different due to the paralysis of the vocal chords. The animal may also travel a long distance from home. Convulsion may be seen and paralysis of the entire body may occur. Dogs and cats usually have the furious form.
The second form is the dumb or Paralytic form. This form results in the animal drawing away from the group. Abnormal movement of the rear quarters is typically seen. Drainage from the eyes and nose is common. Incoordination of the entire body is present. Paralysis of the throat, which causes difficulty swallowing and different sounds of vocalization, is also seen with this form. The ruminants also stop ruminating. Cattle, horses, sheep and goats usually exhibit the dumb form.
Incubation periods in animals vary greatly. The dog may incubate the disease from a minimum of 10 days up to several months (6 months is considered by most to be the upper limit). In cattle a minimum of 25 days to more than 150 days is not uncommon.
It is currently accepted for people in high-risk jobs, such as veterinarians, animal control officers and laboratory workers that deal with the virus to have pre-exposure vaccinations. Post-exposure treatment varies and one should follow the guideline set by the World Health Organization. Prevention is essential for the control of the disease. Vaccination is highly effective. Vaccines are available for most species.
Dogs and cats should be vaccinated as directed by your veterinarian. Remembering most pets are treated as family members and could put your family at high risk for exposure. Having children that show cattle and horses, I always vaccinated the entire show string. Handling an animal will increase your exposure risk. I do feel that a herd in a high risk area should be vaccinated.
Dr. Frankie Bowers, DVM, MS, is the owner of Animal Clinic of the Ozarks a mixed animal practice located in Ozark, Mo.
