[Prev][Next][Index][Thread]
Re: Mad Cow disease and hay mites
In article <317B658A.3BCA@brunel.ac.uk>, Stuart D Neilson
<hssrsdn@brunel.ac.uk> writes
>Oz wrote:
>> You must have come in late. There have been plenty of references
>> quoted, and I don't mean 'The Observer', but refereed scientific ones.
>> Since 'hay mites' is a completely new one to me, perhaps you would like
>> to tell us the paper it referred to, I mean the scientific refereed
>>one?
>
>It is actually a letter from last Saturday's Lancet (Wisniewski HM,
>Sigudarson S, Rubenstein R, Kascsak RJ and Carp RI (1996) Mites as
>vectors for scrapie. Lancet 347:1114). Hay mites (lepidoglyphus
>destructor, acarus farris, tyrophagus longior, cheyletus eruditis, tydeus
>interruptus and tarsonemus spp) were frozen, homogenised and injected
>intracerebrally and intraperitoneally into Compton white mice. Of 71
>mice, 10 were scrapie-positive by the time the letter was written. The
>research was carried out on Icelandic sheep pasture.
Ah, Icelandic sheep. If you have been following the discussion you will
remember that there are now rather good reasons for believing that
scrapie is not the same TE as BSE. Now one of the differences between
BSE and scrapie is that scrapie is found rather well distributed amongst
the various organs (I am not sure about blood), whilst BSE seems to be
confined to the CNS. So to suggest this link is flying in the face of
the evidence unless the ticks are sucking spinal fluid which is (to say
the very least) improbable.
On top of that, of course, is the epidemiological evidence that BSE is
actually decreasing fast and that the evidence is now rather strong that
it is not significantly passed between members of a herd (if at all),
*whatever mechanism you chose to imagine*. We have now got at least
eight years worth of data on that. Since it doesn't noticeably happen,
why are we worrying about it?
So how are you to connect this Icelandic data on sheep scrapie, with
British cows with BSE? Ah, now let's see. Different country, different
species of animal, different disease, and substantial evidence that
there is no route in British cattle with BSE.
Perhaps it would be more accurate to call it an uninformed and
thoughtless mediafest bloodlust.
-------------------------------
'Oz "When I knew little, all was certain. The more I learnt,
the less sure I was. Is this the uncertainty principle?"
References: