Published Date: 2003-09-25 23:50:00
Subject: PRO/AH> Contagious ecthyma, sheep - Ex Australia (02)
Archive Number: 20030925.2424
CONTAGIOUS ECTHYMA, SHEEP - EX AUSTRALIA (02)
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Wed, 24 Sep 2003
From: Richard Brown <REXROCCO@aol.com>
As a practicing vet I can sympathize with the Saudi approach.
It should be possible to be fairly sure of the difference between RVF
and Orf (see Handbook of Animal Diseases in the Tropics; 4th ed.
London: Bailliere Tindall, 1990, pages 337 and 349). So RVF is a bit
of an excuse.
Simplistically, the sheep obviously have some viral infection --
probably contagious, and they don't want a boatload of it offloaded
in Saudi Arabia. Bear in mind that the Orf parapox virus is extremely
long-lived, uses fomites, and is resistant to many disinfectants. One
should think along the lines of an environmental contaminant. Hence
you should never vaccinate on farms that do not have the virus.
Finally your moderator mentions the single Orf skin lesion in man:
correct. He neglects to say that it is damn painful, has an electric
buzz to it, i.e., stimulates nerves, can keep you awake at night, and
you remember and pray for the end of the 10- to 14-day period when
you have it. I think my experience was in line with many others.
Richard Brown MRCVS
[Richard Brown rightly reminds us of the practice of refraining from
Orf vaccination on uninfected premises; as a matter of fact, the very
justification of applying this live vaccine even in affected flocks
is not unequivocal.
As to the disease in man, it seems that symptoms and their severity
may vary in Orf (as they may in other maladies). Your moderator, like
many a vet, had his own share at the time. The lesion lasted longer
(almost 4 weeks) and was not overly attractive, while pain --
fortunately -- seemed to be of a lower magnitude than that suffered
by Richard Brown. My fortune might have been the location -- a
finger, not the face or other sensitive areas. One piece of advice I
take the liberty of giving colleagues and animal breeders (especially
regarding their children!), preferably before but also after they
manage to get infected: try to avoid surgical procedures (including
biopsy), but allow the lesion to take its course, while applying the
standard preparations to prevent secondary contamination or to
relieve pain. - Mod.AS]