Horses in the Grahamstown area have not been affected by an outbreak of African Horse Sickness (AHS) in the province, according to the local state veterinary services, following widespread alarm at a mystery illness striking close to 30 horses in recent weeks.
Horses in the Grahamstown area have not been affected by an outbreak of African Horse Sickness (AHS) in the province, according to the local state veterinary services, following widespread alarm at a mystery illness striking close to 30 horses in recent weeks.
Grahamstown member of the African Horse Sickness Awareness Forum Jenny Copley Foster says 23 horses have died in the Eastern Cape since the start of the warmer weather.
"The state vet has been reluctant to call this an AHS outbreak, however," said Copley Foster. "Only four cases have been confirmed as AHS."
The first reports of the suspected outbreak came from Kei Mouth and Morgan's Bay, north of East London, she said.
"By last Wednesday [2 January], authorities had received reports of 29 horses falling sick. Of these, 23 have died, including one in Port Elizabeth."
The African Horse Sickness Trust's website, under the heading 'Early Warning System: 2012/2013 outbreak', says there have been 21 cases in the Eastern Cape.
According to the website, cases – not all confirmed – have been reported in other areas of South Africa, including Mpumalanga, Gauteng and Namibia. From one case reported to the site in November, the figure jumps to 21 cases in December.
Authorities are concerned.
"The problem is that people don't vaccinate," manager for state veterinary services in Grahamstown, Jane Pistorius, told Grocott's Mail on Friday. "Fifty percent of the people in the area where this latest outbreak occurred don't vaccinate their horses."
Copley Foster confirmed that a number of the dead horses in the Eastern Cape had not been vaccinated.
"Horse owners are reminded that they have a legal obligation to immunise their horses effectively each year," she said.
"All suspected cases of AHS must be reported to the State Vet and samples collected from dead horses should be submitted through the vet for analysis at the Equine Research Centre in Pretoria."
Copley Foster said two horses had been reported sick in Riebeeck East. One had died. The cause of the illness had not been established, however.
She said many of the deaths in the province had been characterised by the horse's sudden collapse, with no early symptoms.
Confirming that 29 horses had been reported sick, Pistorius did not venture an explanation for cases testing negative for AHS.
"We try to identify cases of African Horse Sickness, but we don't go beyond that," Pistorius explained.
She said AHS was a notifiable disease, meaning cases must be reported to the state vet. A campaign was under way to systematically vaccinate horses in the area of the outbreak, Pistorius said.
Grahamstown, she said, was not under threat from the East London outbreak.
"We haven't had an outbreak here for a few years," Pistorius said.
Explaining what the threat was, and what had caused the outbreak, she said, "The disease is not directly contagious, but the weather has been perfect for the miggies to breed."
It was these biting midges, Culicoides imicola, boosted to breed by the recent rain and heat, that infected horses with the virus [Orbivirus], Pistorius said.
"The risk is moving horses through the areas where the insects are active."
She said another case of AHS had been confirmed on Thursday, bringing the confirmed cases to nine.
"There was a suspected case in Port Elizabeth, but it tested negative," Pistorius said.
According to Copley Foster, horse sickness manifests in three ways:
- * Cardiovascular form affects the heart, lungs and other organs. Known as 'dunkop', it has a recorded 95% mortality rate.
- * The 'dikkop' form, affecting principally the brain and eyes, results in significant swelling of the head and bulging of the eyes, which may also bleed. The mortality rate for this form is around 50%.
- * Third, there is a combined form, which horses rarely survive. Biliary can be a contributory factor and owners are advised to monitor their horses carefully for any early signs of ill-health and take appropriate action.
"There is no known cure for the disease, although some supportive therapies have a high success rate if implemented correctly and consistently," said Copley Foster. "Intensive nursing of the sick horse is critical, as is the relief of pain and control of extreme temperatures.
"The crucial, unanswered question for many desolate horse owners is this – if we are not in the grip of an AHS outbreak, then what is killing our horses?" Copley Foster asked.
For additional information contact the vet, log on to the AHS Facebook Group at https://www.facebook.com/groups/fightAHS/ orwww.africanhorsesickness.co.za, where regular updates are available.