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RIVM
To
Ministry of Agriculture, Mrs A. Burger,
Ministry of Public Health, Mr P.H. Huyts
Subject
Advice for culling policy and killing methods of goats infected with Q-fever.
Date
15 December 2009
Dear Mrs Burger, dear Mr Huyts,
On Friday afternoon I received your request for advice regarding the various options of killing methods
for pregnant goats and sheep at infected farms. During the meeting on 14 December four other questions
were laid down before the experts.
Two of those questions were elaborately answered in the letter from the CVI (Mr Bianchi) to the CVO
(Ms Bruschke). The other experts whom we consulted support the advice of the CVI. We have attached
the CVI report.
The other questions I have put before veterinary experts and an ‘arbo’ (= employment) expert.
The experts emphasise that the advices regarding the killing methods are focused on limiting the
dispersion of C. burnetii from infected animals by minimising the number of handling the animals and
limiting the locations where animals are taken to. It is important to keep the risk for employees as low as
possible.
I will give you the substantiations and answers point by point.
Question 1.
Concerning non-vaccinated farms with positive bulk milk test.
What effect can we expect from vaccinating pregnant animals?
Considerations
There are no reliable data available. Part of these animals will already be infected, even when the test is
not (yet) positive. In such cases vaccination does not reduce the spreading of Coxiella burnetii. A
number of these animals will not yet be infected. There is doubt about the effect of vaccination of
pregnant animals, but also a lack of useful data regarding goats.
Advice
The experts believe that vaccination of pregnant animals does not result in the desired effect on
excretion of C. burnetii. See further comment and substantiation given by the CVI.
Question 2.
Concerning vaccinated farms with positive bulk milk test.
Would it be possible to make a distinction between high and low contamination farms?