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The Zika
Virus
I am
sure you will have heard about the Zika virus that is causing concerns in
Brazil and South America. The disease is spread by mosquitoes and mainly
symptoms are mild. Four out of five people are reported to have no
detectable symptoms, others suffer a mild fever sometimes with a rash and
joint pain. The most common symptom is conjunctivitis, red eyes which seems
to be the trigger to test for the disease. The Zika virus is causing such
concerns because if it gets established early in pregnancy it can affect the
development of the foetus altering the way the brain and head grows. No body
knows what the long term affects will be on a growing child, the prospects
are not good.
Sounds Familiar.
When I first heard about this it seemed to be very similar to the
Schmallenberg Virus that we used to see in new born lambs three years ago.
Affected lambs had severe deformities of their head and face and were
usually born dead. It was a difficult disease to understand as often twins
or triplets in the same pregnancy were not affected. You will remember that
Smallenberg was transmitted by a midge, and was not detectable until
deformed lambs appeared. After the initial outbreak few cases were seen so
the assumption is that although the infected midges are still about sheep develop
an immunity early in
their lives and do not suffer abnormal pregnancies.
Vaccine Development.
The symptoms of the Zika virus in adults are similar to Dengue
fever which is also spread by the same mosquito that bites during the day.
Heroic efforts to spray the places where the insects breed with insecticide
look good on television, but they are not the answer for longer term control
of the virus. A vaccine for pregnant women is a priority at the moment,
especially as there is the prospect that the disease could spread with the
mosquitoes to North America this summer.
Blue Tongue History
Nine years ago all of the talk was about Blue Tongue and we were
all consulting our old text books to rediscover what we had forgotten about
this tropical disease. Fortunately at that time the drug companies were able
to modify the Blue Tongue Vaccines that they were selling in tropical
countries and soon we had the means to combat the infection. Looking back
the impact of Blue Tongue was worse in the south of the country because it
got established there first and when it started to have an impact here the
vaccine had arrived and it soon faded away.
Blue Tongue Now
In the intervening years Blue Tongue does not seem to have been
so active on the continent, presumably most cattle and sheep had a good
immunity from either the vaccine or the natural infection and nobody has
talked about it for a number of years. As soon as the disease disappeared so
did the vaccine. At its peak there were I think four companies promoting and
selling the BTV8 vaccine, but nobody makes it any more. DEFRA have become
concerned as last year Blue Tongue started to make a comeback on the other
side of the channel and they are predicting that there is an 80% chance that
it will cross over to us at some time during the summer.
No Vaccine available now
The official advice it that if you are concerned about Blue
Tongue in your animals you should consult your Veterinary Surgeon. What your
Veterinary Surgeon would like to tell you is that DEFRA has realised that
there might be a problem with Blue Tongue this year and they have
commissioned a supply of vaccine that will be available in May before the
midges become active to put your stock at risk. Unfortunately this has not
happened yet so I am not sure what to tell you. For the infection to get
here it needs to move up from central France to the coast, then when there
is an established population of infected midges it can only get here when
the wind and weather conditions are wrong for us.
Slow Progress
The chances are for all of this to happen it will be late in the
summer before it comes back if at all. As I remember it those troublesome
midges tend not to venture out on cloudy or windy days so if it does get
here later in the year it will hopefully not get this far north before the
winter puts a stop to its progress.
Badgers found Dead in Wales
This week the Welsh Assembly announced that it is to continue
with the badger found dead survey throughout the country for a further
twelve months at least. This gives valuable information about where the
infection is active and where it is likely to go next. Sadly there is no
indication that a similar scheme could be organised in England at least in
the dwindling low risk areas where it is vital to know where the infection
is going as the cattle testing interval can be as long as four years still
in some places.
Interpreting Numbers
I have always marvelled at the way that people who are good with
numbers can be so confident that their interpretation of figures must be
correct. The only time that there was the slightest hint that there was to
be a government with a comfortable majority was at one minute past ten on
election night. Now we are told that the computer model predicts that it
will make no discernable difference if after four years there is a year when
no badgers can be vaccinated because of a shortage of the BCG vaccine. They
say that if it is available next year, and it is a big if, the ultimate
outcome will be the same. So why not have a break year anyway and save us
all a significant amount of money.
Latest Tuberculosis Figures
Yesterday I happened to come across the statistics for new herd
breakdowns and numbers of cattle slaughtered for the twelve months up to the
end of November Last year. These are compared to the same period in 2014.
During the past twelve months 27,982 animals were slaughtered in England
that is a 9% increase on the year before. The figure for Wales is 7,668
which was 25% more than the previous year. Also of concern is the rise in
the number of farms in the low risk area which are under restrictions these
are up by 51%. I do accept that you can be deceived by one set of
statistics, but it is not very often that I come across figures that show
any encouraging trends about tuberculosis. The only thing that I can see on
this sheet of paper that seems good to me are that in Scotland in the twelve
months to the end of November 2015 only 23 farms were under movement
restrictions because of tuberculosis, 121 cattle were slaughtered during
that period which is a reduction of 47% on the previous twelve months.
Wilf Davies
February has been a sad month for us at the Malthouse because of
the passing of one of our long standing friends. Scarcely a day passed
without a visit from Wilf. He told us the sheep prices at Welshpool and all
of the village gossip long before it appeared on facebook. Somehow Wilf
seemed to know when we were having a quiet afternoon and was always good
company when there wasn’t much else going on.
Wilf has taught us a great deal about livestock. Over the years he
had several ponies that pulled carts through the village. Oblivious to
traffic he was always in control and would get his last pony Joanne to
squeeze in between the parked cars to allow others to pass. Somehow Wilf’s
ducks would always start to lay at least a month before everyone else’s
and just how do you get your hens to lay eggs with double yolks in the
winter is something that sadly we will never know now. A talented stock man
we will never forget you.
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