A Professional Diagnostic
Service - Dr. Ruth Watkins'
proposals
I would like to present the
concept by illustrating how it might have been had such a diagnostic Service
been in operation in February 2001.
A: In preparation for an
epidemic
Daily diagnostic work will
have prepared for emergencies.
- Work will not have been
confined to just one or two viruses; a large number of specimens and
clinical veterinary problems will have flowed into the lab all the time.
- Equipment will be modern
and used every day so that when the emergency arises, excellent
equipment is in place.
- The testing of 50-100
farms a day will pose no major problem.
B: Development of
up-to-date testing methods
- Liaison with and advice
from other important laboratories and from work on other viruses will
have provided the Diagnostic Service with the latest advances.
- For example, it will be
well known that nucleic acid extraction and real-time PCR offer advances
on the older PCR methods in terms of sensitivity and accuracy.
- Commercial companies
will do quality control, and scaling-up test numbers can be better done
commercially than in-house.
C: The preparation of
virology policies and protocols for the management of the outbreak will be
under the personal control of the lead virologist on the team
- The important reason to
have the veterinary virologist ultimately responsible is that he is
obliged to form a view on best practice by consulting widely with
research virologists, epidemiologists, and virologists from other
countries (e.g. Dr Sutmoller amongst many Europeans)
- A balanced view of best
practice - and most importantly on the use of vaccination - will have
been formed.
D: Dr Paul Kitching (for
example), as virologist responsible for the service, would not agree to
anyone other than he or his laboratory staff should interpret the laboratory
results. It is poor practice to pass
the results of tests to another outside the laboratory for interpretation.
- He would issue printed
reports and interpret results on all specimens. (It is good practice to
issue printed reports: conversation can be easily misinterpreted and
misunderstood.
- FMD is not difficult to
diagnose in the laboratory when the appropriate specimens are taken from
an animal exhibiting symptoms and signs of illness.
- A negative laboratory
result excludes FMD infection.
- There is no rational
basis for disregarding the laboratory.
E. Work once the outbreak has
occurred The veterinary virologist
(Paul Kitching, for example) is the hub.
- All relevant persons,
especially the field veterinary surgeons, are given the instructions for
sampling farms where infection is presumed - and further instructions on
sampling with regard to vaccination. There are clear rational
explanations.
- Field vets contact Paul
Kitching and his staff, not Page Street. The virology can be
explained and differential diagnosis discussed, samples to be taken etc.
- Paul Kitching will be
responsible for the flying field laboratories doing near-farm testing by
PCR and antigen assays, ensuring that confirmatory specimens were also
sent to the laboratory.
- Paul Kitching and his
staff issue printed reports to every field vet giving the interpreted
results. Fax is quick and useful.
- These results are passed
to DEFRA so that there is an accurate epidemiological database.
- The laboratory results
are used to confine culling to infected farms and trigger local limited
vaccination of all susceptible animals with the aim of controlling the
spread of infection.
There has been a failure
to learn from the 2001 UK epidemic.
- failure to test the
culling policy of contiguous premises or over 3km premises against
independent data such as laboratory results
- failure to apply
vaccination in at least some areas
- failure to assess anti-NSP
tests
- failure to learn about
the spread of FMD under different circumstances such as extensive
grazing on the Brecon Beacons where there is in fact no hard evidence of
its spread outside the single infected heft whilst up on the mountain.
There was a failure to
apply what was quickly
learnt and published by Dr Donaldson; the lack of aerosol spread of the
epidemic strain, which rendered the 3km culling policy unnecessary.
A virologist would have
planned to learn as much as possible. However, virologists were sidelined
during the UK epidemic.
Without authority given to
specially trained and dedicated virologists I can see no hope yet that
should FMD recur in Britain we are ready to do any better.
Will we continue to make a hash of animal infectious disease?
This has an important implication for human health - just take bovine TB for
example, caused by Mycobacterium bovis. This was unjustifiably
neglected in the FMD epidemic. There has been a resurgence as untested
cattle have been moved all over the country, even from the known residual
hotspots, with the spread of TB to previously uninfected herds. What of the
dedicated and highly trained veterinary microbiologists?
|