Re: Re: African Horse Sickness

["Tracey" <tracey@tbt.co.za>]

Curious Sylvia wrote:

>
>Could you guys explain what this is?  It sounds like you have to quarantine
>your horses for 6 weeks every year?  Sounds awful!  Why and how does the
>whole thing work?


African Horse Sickness is a virus spread by midges (nasty little flying
biting things which surface on about 15 August each year and disappear on
about 14 August the following year, thereby dispelling all previously-held
beliefs that AHS was a "summer disease")


There are two types : dunkop (thin head) and dikkop (thick head).  Dunkop is
the major killer, probably because it is not as immediately obvious, and
therefore not treated as quickly.


Symptoms are elevated temp, high pulse / resp, sensitivity to light,
sometimes swelling of the head (it seems to affect fluid around the brain?
Help me out, here, Celeste).  Horses simply stop eating, and, if not
treated, die.


I know of a horse who went on a nice hack, happy as a lark, in the morning,
and was dead at 4pm that afternoon.


There are two vaccines for the disease, which are given three weeks apart.
Because you are administering a miniscule quantity of the disease, which can
strain the heart and other vital organs, you have to work your horse very,
very carefully, to ensure that no strain is placed on these organs.  For
this reason, until recently, racehorses were not vaccinated against it : the
trainers would not leave them out of work.  Now that the disease is so
rampant (probably because the weather is that much warmer that the midges
are not dying out in winter) even the racehorses are being vaccinated.


The "critical" period is in the so-called "middle" week of each injection
(ie seven days after administering the injection to fourteen days after)
when you should do no more than walk your horse.  Friends of mine with hot
horses will not even ride theirs then, in case they get themselves heated
up.  I usually leave mine alone, as well.


Any work which will elevate the heart-rate is a big, big no-no.


We don't have to quarantine our horses, as it is not spread by contact,
although only an idiot would take a horse out who had AHS.


Other measures to prevent it are : no lights on in / near stables in Summer
(nothing like mucking out in the dark), fly spray horses four times per day,
horses go out only when the grass is dry, and come in at about 4pm, fly
spray stable walls to prevent midges from entering stables, take temps
morning and night and phone vet at the first sign of elevated temp.  I also
take pulse and check resp, but I'm a bit anal.


Some people put old hay and manure into drums and burn it outside stables -
the foul smell is supposed to keep midges away.  I think you could just as
easily cause resp problems for the horse.


Also, don't allow any stagnant water on the ground near the stable as midges
breed in it.  I keep ducks in a pond near my stable, because they eat the
larvae and also run around like little robots all night killing the midges,
with Mark and I yelling support out the back window.  We don't get out much.


Anything I've left out, Celeste?


Oh, yes, AHS is the primary reason why the Olympic Games will never, ever,
ever be held in South Africa.  No way would the FEI allow international
horses to compete here.


Tracey