As of August 11, 2015, the first anthrax case in Texas has been confirmed and quarantined in an equine in Uvalde County. The Texas Animal Health Commission (TAHC) has quarantined the premises. TAHC rules require proper disposal of affected carcasses and vaccination of livestock on the premises prior to release of the quarantine.
New horse disease alerts
Horse owners are being alerted to a newly confirmed case of anthrax in Texas, the first in 2015, and in addition, new cases of Eastern equine encephalitis and strangles have been confirmed and quarantined in Florida.
Anthrax is an acute, rapidly-developing, fever-producing, infectious disease that requires the immediate attention of an equine veterinarian.
In horses, anthrax may take either a pulmonary form with fever, muscle pain, respiratory distress, sweating, and shock-like symptoms, or it may take a gastrointestinal form with fever, colic, and bloody diarrhea. Common symptoms include septicemia, enteritis, and colic.
Stricken animals may die within one to three days. Failure to achieve rigor mortis after death is common.
Characterized by a high fever, anthrax progresses rapidly. In addition to a high fever, horses are obviously sick and often have ventral edema. If the horse dies, the carcass will likely have dark blood oozing from the mouth, nostrils, and anus. .
Because anthrax is known as "the quick killer," diagnosis may be based on the clinical signs, but it is routine to confirm the presence of Bacillus anthracis from a blood sample or culture sent to a laboratory.
In Jefferson County Florida, a new case of Eastern equine encephalitis has been confirmed in a donkey. The donkey, a 17 year old unvaccinated jack had not been off the property in 6 months. Clinical signs began July 25th and progressed until the donkey died of natural causes on July 28th.
The case was confirmed positive by the Georgia Department of Agriculture on August 5th. This is the first confirmed case in Jefferson County and the 18th positive in Florida since the beginning of the year.
EEE virus attacks the central nervous system and unvaccinated horses are very susceptible to the infection. The disease appears within five days after a mosquito transmits the virus to the horse. Onset of clinical symptoms are abrupt and infected horses often die within three days.
The fatality rate is 90% or higher and an animal that survives the disease may have brain damage.
Other diseases and poisoning may have similar symptoms. It is important that a speedy diagnosis is made. A veterinarian can take blood samples to send to a diagnostic laboratory.
A new case of strangles has been confirmed in St. Johns County, Florida. Currently one horse of the two horses on the property are clinical. The symptoms started on August 4th and PCR testing returned positive on August 10th. Currently the premises are under quarantine. This is the first confirmed case in St. Johns County and the 20th incident for the state since the beginning of 2015.
The name "strangles" was coined due to the strangled breathing sounds made by horses with enlarged lymph glands that are characteristic of the disease which is caused by Streptococcus equi .
A horse that is exposed to Streptococcus equi will begin to show symptoms within two to six days and the characteristic abscessed lymph nodes will develop within one to two weeks after exposure. The lymph nodes rupture and drain and the drainage is highly contagious.
Separating or quarantining a horse at the earliest signs of the disease is important because the disease is highly contagious and may be passed from one horse to another via nasal secretions and pus from ruptured abscesses in the lymph nodes. Horses remain contagious for approximately a month after having the disease.
Good horse management techniques are necessary to prevent the spread of the disease through contaminated water buckets, brushes, stalls, fences, or any other surface in the stable or pasture area. Bleach or other disinfectant should be used to wash down stalls including walls and floors, all equipment and tack, and any other surfaces that may have become contaminated by a horse with the disease. Fortunately, the bacteria die fairly quickly in the environment.