- Hello, Jeff -
-
- As for bovine condition that lead to polio-like symptoms
in ruminants, I doubt that it is botulism or any known virus agent. I
do find it "interesting" that a case was documented in Switzerland.
Switzerland did have atypical scrapie.
-
- I have a feeling that this is a brand-new disease.
I am also wondering if we will begin to see a similar condtion in humans
as we did when BSE/vCJD was identified.
-
- Patty
-
- [1] Date: Fri, 11 Jun 2004
-
- Statement On Undiagnosed Nervous Condition In Ruminants
-
- Defra Statements 8 Jun 2004, accessed 11 Jun 2004 [edited]
-
- The [UK] Veterinary Laboratories Agency [VLA] has recorded
what is possibly a new condition in ruminants in England.
-
- A short item was considered by the UK Zoonoses Group
on a nervous condition in a heifer that had suffered partial leg paralysis.
It was initially diagnosed as suspected botulism.
-
- The UK Zoonoses Group's [UKZG] remit includes consideration
from a public health angle of new and emerging diseases, such as the case
brought by the VLA in April 2004.
-
- Tests on the animal at VLA Penrith, Cumbria, showed on
microscopy lesions suggestive of a viral infection in the brain. There
was no evidence of a Transmissible Spongiform Encephalopathy.
-
- Possible virological causes were followed up, including
louping-ill, infectious bovine rhinotracheitis (IBR) and West Nile virus.
All proved negative to the tests. The lesions were also not consistent
with Borna disease infection or rabies infection.
-
- Over the last 10 years, 21 similar cases from 13 premises
have been identified by the VLA as a result of their examination of routine
submissions. The VLA carries out extensive surveillance and diagnostic
work on material submitted by private vets for their farming clients. In
the submission of the material, a diagnosis is not reached in every case.
-
- A similar pathological condition has been recorded in
Switzerland following surveillance similar to that carried out by the VLA.
-
- The issue was raised at the UKZG in advance of publication
of a letter to the Veterinary Record, alerting vets and farmers of the
findings. The letter is due to be published shortly.
-
- Further investigation is ongoing, and the Health Protection
Agency is to lead a risk assessment on the new condition. Chief Veterinary
Officer Dr Debby Reynolds has asked that this be done as a matter of urgency.
-
- NOTES: The UK Zoonoses Group (UKZG) is a high-level forum
for the discussion of animal and human health aspects of zoonoses (diseases
and infections transmissible between animals and man) and their control,
chaired by the UK Chief Medical Officers. Its terms of reference include
providing an overview and means of ensuring overall co-ordination of public
health action at the UK, national and local level with regard to existing
and emerging zoonotic infections.
-
- http://www.defra.gov.uk/news/statements/040608.htm
-
- ProMED-mail promed@promedmail.org
-
-
- [2] Date: Fri, 11 Jun 2004 From: Mary Marshall <tropical.forestry@btinternet.com>
Source:
-
- Undiagnosed Condition In Ruminants
-
- The Veterinary Record 12 Jun 2004, vol 154, no 24, Letters,
pp 766-7 [edited]
-
- The differential diagnosis of tetraparesis/paralysis
in cattle includes botulism, metabolic disturbances including hypocalcaemia,
trauma, breed-related disorders and viral encephalitides such as louping
ill.
-
- Here we report a case of in a Holstein heifer with a
provisional clinical diagnosis of botulism, based predominantly on the
clinical findings of flaccid paralysis. Further reasons for the suspicion
of botulism were the presence of a dead crow in the water trough in the
field; that there was a large chicken broiler unit 3 km from the farm;
and that there had been a previous case of suspected botulism, 3 months
previously, at a neighbouring farm 1 km away. Although no definite source
was identified in that case, the clinical signs and history were typical,
and no alternative diagnosis was obtained in PM examination. The present
case became recumbent following progressive flaccid paralysis over 5 to
6 days. Moderate weakness, hind-limb ataxia and a slightly stiff gait were
also noted in a 2nd heifer, which gradually recovered over several weeks.
-
- The recumbent heifer was euthanised and submitted to
the Veterinary Laboratories Agency (VLA) - Penrith for a PM examination.
No macroscopic lesions were noted. Histological examination revealed subacute
bilateral non-suppurative and necrotising polioencephalomyelitis, characterised
by perivascular cuffing, glial nodule formation and occasional neuronal
necrosis, mainly involved dorsal and ventral horns (first cervical segment
of the spinal cord), medullary reticular formation, vestibular complex
and red nucleus. Immuno-staining for louping ill virus, bovine herpesvirus
type 1 and West Nile virus antigens were negative. Joest-Degen bodies and
Negri bodies characteristic of Borna disease virus and lyssavirus infections
(respectively) were not detected. 10 in-contact heifers, including the
recovered animal, were seronegative for louping ill.
-
- The differential diagnoses of bilateral polioencephalomyelitis
in man are neurotropic viral infections and paraneoplastic encephalosis
(Love and Wiley 2002). Louping ill virus infection, the only cause of encephalitis
of this distribution and character currently recognised in ruminants in
the UK, was ruled out in this heifer. Over the past 10 years, 21 cases
of ovine and bovine non-suppurative and necrotising polioencephalomyelitis
characteristic of neurotropic viral infection but negative for louping
ill antibody and/or antigen, from 13 farms throughout England, have been
detected by regional laboratory surveillance. A full set of laboratory
data is not available from many cases, because these were identified retrospectively.
-
- However, preliminary laboratory data, immunohistochemical
results and lesion distribution strongly suggest that the lesions observed
in these sheep and cattle are unusual or new presentations of encephalitis
caused by a known virus or one or more novel viruses. It is possible that
the causative agent is a common ruminant virus that is only occasionally
neurotropic, for example, an enterovirus. Theil and others (1998) found
no evidence of rabies, Borna disease or tick-borne encephalitis in similar
cases of viral-type encephalitis in a series of 48 cattle in Switzerland,
although they presented preliminary evidence of possible morbillivirus
infection in 4 cases.
-
- In the absence of a reliable confirmatory test for botulism
in cattle, this case illustrates the importance of ruling out other possible
causes of tetraparesis/paralysis in cases of suspect botulism. Further
research work will be required to identify the causative agent(s) of these
ruminant polioencephalomyelitis cases.
-
- -- P.J. Watson, VLA Penrith, Merrythought, Calthwaite
Penrith, Cumbria CA119RR.
-
- S.F.E. Scholes, VLA Lasswade, Pentlands Science Park
Bush Loan, Penicuik Midlothian EH 26 OPZ.
-
- References ---------- Love S & Wiley CA. (2002).
Viral diseases. In Greenfield's Neuropathology. Vol 2, 7th edition. Editors
Graham DI & Lantos PL. London, Arnold. Pp 1 - 105.
-
- Theil D, Fatzer R, Schiller I, Caplazi P, Zurbriggen
A, & Vandevelde M. Neuropathological and aetiological studies of sporadic
non-suppurative meningoencephalomyelitis of cattle. Vet Rec. 29 Aug 1998,
vol 143(9):244-249.
-
- -- ProMED-mail <promed@promedmail.org>
-
- [Anyone engaged with the diagnosis of botulism in cattle
is familiar with the frustrating difficulty of obtaining reliable, clear-cut
laboratory confirmation of suspected clinical cases. Similar to the observations
of the authors in the current case, in many cases diagnosis has to be based
upon clinical and circumstantial indirect evidence (see references). The
authors deserve to be commended for extending their investigation to include
histopathological and immunological examinations. This case demonstrates
the importance of forwarding specimens from a maximal number of suspected
cases to laboratories or investigation centres. It is possible that similar
findings will be encountered in other countries, provided laboratories
are properly equipped and diagnostic services are readily available to
farmers and practitioners. Since gross economic interests -- and, most
important, public health -- might be at stake, such diagnostic services
should be easily accessed, with maximal state support and minimal bureaucratic
or financial barriers.
-
- The public-health aspects of the described case have
not been addressed in the paper. They might have been overemphasised in
the media. This might be the product of 2 main factors: the involvement
of UKZG, and the use of the (correct!) term polioencephalomyelitis, which
led the media to regard the case as being "polio-like", thus
related to human health.
-
- The Swiss paper referred to, written by workers of the
Institute of Animal Neurology, BSE Reference Centre, University of Berne,
indicated that 51 such cases diagnosed over a period of 10 years were examined
retrospectively to investigate whether they constituted one or more distinct
diseases, and to search for etiological agents. PCR amplification for chlamydial
DNA was negative in all but 1 of 32 specimens.
-
- Immunohistochemistry did not demonstrate the presence
of chlamydial antigens, either in the one PCR-positive case or in the other
cases examined. Immunohistochemistry for rabies virus, Borna disease virus,
and central European tickborne encephalitis virus was negative. In 4 cases,
immunolabelled cells were found in the lesions with antibodies against
paramyxovirus antigens.
-
- Though this might just reflect the highly efficient Swiss
veterinary surveillance system without -- in the current case -- BSE-related
implications, interestingly Switzerland was the 1st country in continental
Europe to identify, as early as 1990, endemic BSE.
-
- Further results from the ongoing investigations, with
special reference to excluding human-health hazards, and -- foremost --
observations in other parts of the UK and the world at large, are anticipated.
- Mod.AS]
-
- [I find the situation unsatisfactory for the following
reasons. Amazingly, NO EM work is reported, which could clarify rabies
or the fascinating clues to morbilli/paramyxovirus involvement. Rabies
was not given as a differential diagnosis in the UK case, and apparently
not excluded -- the absence of typical lesions and of Negri bodies mentioned
is not conclusive. There are numerous reports of lyssaviruses (rabies group
viruses) in bats in Europe, including the UK -- see: Rabies, bat - UK (Lancashire):
confirmed 20021002.5447, on an infected bat that bit a woman. Why were
there no viral isolation attempts in mice or tissue culture, or brain histo-chemistry
for lyssaviruses? - Mod.JW] ---- Botulism, cattle, suspected - UK (Northern
Ireland) 20020315.3750 1998 ---- Botulism, bovine - USA (California) (02)
19980424.0763] ....................arn/pg/jw
-
- Patricia A. Doyle, PhD Please visit my "Emerging
Diseases" message board at: http://www.clickitnews.com/ubbthreads/postlist.php?Cat=&Board=emergingdiseases
Zhan le Devlesa tai sastimasa Go with God and in Good Health
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