A Professional Diagnostic Virology Service

Dr Ruth Watkins

(formerly Consultant Virologist, St Mary's Hospital, London)

Based on a Report Prepared for the EU Commission Inquiry into FMD 31st August 2002

I would like to present the concept of a specialist veterinary virologist led service in the context of the FMD epidemic in the UK by illustrating how it might have been. I would like to pick out points that in my opinion could have made a material difference to the handling of the epidemic. These will be set against what actually happened.

Job description for a specialist veterinary virology consultant

Responsibility for the provision of a virus diagnostic service
Advice on differential diagnosis and sampling
Laboratory testing and interpretation of results
Advice on management including the use of vaccines
Control of infection
Producing policies and protocols
Playing the lead role in managing outbreaks of veterinary virus infection
Education and liaison
In-house staff, vets in general and others such as DEFRA employees
Development of diagnostic techniques to improve and modernise the service

Apart from basic veterinary training the appointee should have a higher specialist training covering all veterinary animal viruses that could be relevant to UK practice and have both clinical veterinary experience in infection and laboratory training and be a member of the Royal College of Pathologists by examination. This sounds a tall order but there are many specialists in human medicine with higher specialist training of which there is no equivalent in veterinary medicine- the laboratory based specialists in microbiology or virology have a job description as outlined above.

Research scientists must publish lots of papers and raise as much money for research as possible and they are appraised on this. I am not sure what the SVS officials from Page Street MAFF DEFRA headquarters are appraised on but they do not have the ongoing responsibility and knowledge that hands on experience of running a virus laboratory brings. The appointee would be appraised on the provision of service not research.

When an epidemic is discovered a research scientist cannot be expected to step out of the research institute at Pirbright nor an SVS vet from behind his desk in Page Street suddenly to provide the competent professional service that would be provided by the dedicated person just outlined, the veterinary virologist with a thoroughly grounded professional competence. Professional competence consists of being prepared.

Work prior to the FMD epidemic-preparation

A. Why should there be a value in the daily diagnostic work of the veterinary virologist? In fact the daily work prepares for an emergency such as an outbreak of FMD because scaling up using the laboratory facilities in routine use accommodates the increased workload such an epidemic brings. It is important that the diagnostic laboratory is not confined to one or two viruses as this limits the daily flow of specimens and clinical veterinary problems into the laboratory and makes investment into equipment used only occasionally wasteful and probably ineffective.

What actually happened

Automation was put in place only 3 months after the epidemic started
Computerisation was not fully in place, all specimens were hand numbered rather than given printed labels and barcodes
In house tests were not modernized: ELISAs still relied on hand washing at the start of the epidemic

This is normal practice for research labs but inadequate for a diagnostic service involving many specimens. Testing must be robust and timely. Receiving specimens from 50 to 100 farms a day to diagnose FMD should not be a major problem for a diagnostic laboratory.

B. Development of modem testing methods is important. Looking at what is happening in other labs and on other viruses helps. For example nucleic acid extraction and real time PCR offer advances on the older PCR methods in terms of sensitivity and accuracy. Rapid tests for the presence of virus are essential to the practice of modem virology - rapid tests are those that take only a few hours to complete. It is a point of good laboratory practice to use the best available tests even when these are not in-house. In fact commercial companies do quality control and scaling up test numbers better than it can be done in-house.

What actually happened

Being constrained by financial resources to developing in house tests at Pirbright for the market seemed to lead to a reluctance to evaluate any one else's tests including those offered by commercial companies and the USDA.
There was a failure to recognise the value to the management of an epidemic of the near farm PCR test a rapid test offered by the USDA. Also to seize the opportunity to evaluate it. By the time culling was done on many farms, their contiguous and dangerous contacts, and the 3 km culling, results from rapid antigen and PCR tests would have been available from the index farm (clinically suspected infected premise). When the index farm tested negative, culling need not have carried out on the other farms, even on the index farm. All those farms placed on section D notices on account of a negative index farm need not have been (they have never received any compensation for their losses).
There is a duty to evaluate tests upon any laboratory that has a monopoly as Pirbright does on FMD in the UK. This was ignored.

C. The team assembled to prepare virology policies and protocols for the management of an FMD outbreak would be lead by a veterinary virologist. An important reason to have the veterinary virologist ultimately responsible is that he is obliged to form a view on best practice, a view not reached alone and requiring the endorsement of one's peers. Prejudices based on research interest should not influence the policy (Here I mean perhaps undue concern over the importance of vaccinated carriers in spreading the virus). He would be able to form a team and consult widely with research virologists, epidemiologists and virologists from other countries with first hand experience in FMD (e.g. Dr Sutmoller amongst many Europeans). During “peacetime” a balanced view would be formed - most importantly on the use of vaccination. The virology policy could be taken up by the ministry DEFRA and other stakeholders, worked through and tested by dummy runs. Updating the FMD policy would occur as the lead virologist is aware of and in touch with the progress of FMD infection and the emergence of new viruses in the way that an official of DEFRA cannot be.

What actually happened

No such updated FMD policy and protocol existed in preparation for an FMD epidemic. I believe this was because no virologist had authority and responsibility to prepare one.

D. The virologist responsible for the service would not agree that anyone other than he or his laboratory based staff should interpret their own laboratory results. It is poor clinical practice to pass the results of tests to another outside the laboratory to interpret. He would be in the practice of issuing printed reports and interpreting the results on all specimens. It is also good practice to issue a printed report rather than rely on conversation, which can be misunderstood.

What actually happened

MAFF commissioned Pirbright to do the FMD testing and assumed that it therefore owned the results.
Persons unfamiliar with the virology laboratory interpreted the laboratory data according to a written protocol provided by Pirbright.
A printed report was not given to the vet who saw the farm with suspected FMD infection, who never saw the results at all.
Results were given over the telephone to the local MAFF DEFRA headquarters.
Officials who had no specialist training in infection, virology or FMD gave advice to vets over the telephone from Page Street
Persons who had no professional virology training made the judgment that 'confirmed infected premises' would be considered confirmed from clinical observation alone regardless of the laboratory result.

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.

Work once the outbreak of FMD has occurred

The veterinary virologist is at the hub.

I. The protocol and policy documents he has been instrumental in preparing are distributed to all relevant persons especially the field vets. This contains instructions on the correct sampling amongst other information. There are also instructions for sampling presumed exposed farms and further instructions on sampling with regard to vaccination. There are clear rational explanations.

II. The veterinary virologist and his staff take calls from field vets, not Page Street. The virology can be explained and differential diagnosis discussed and the samples to be taken etc.

III. The veterinary virologist would be responsible for the flying field laboratories doing the near farm testing by PCR and antigen assays, ensuring confirmatory specimens were also sent to the laboratory. There were no field laboratories during 2001 though some vets attempted to use the pen-side antigen test in the latter part of the epidemic.

IV. The veterinary virologist and his staff issue printed reports to every field vet giving the interpreted results. Fax is quick and useful. The field vets never saw the results and it is doubtful they learnt to diagnose FAD with any clinical accuracy without knowing or believing the laboratory results.

V. These results are also passed to MAFF DEFRA so that there is an accurate epidemiological database. The database was inaccurate in more ways than one during the 2001 outbreak. The curves should be redrawn taking into account only the farms testing positive in the laboratory and republished now that DEFRA have admitted that a farm with a negative laboratory result can no longer be counted as a confirmed infected premise.

VI. 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. In 2001 there was much bullying and coercion to persuade farmers to have stock culled that were healthy or did not have FMD on laboratory testing. Dictatorial and threatening tactics were employed. Vets ringing Page Street were forced to order the culling of a farm even against their clinical judgment without waiting for results.

There has been a failure to learn from the UK epidemic, e.g. to test the culling policy of contiguous premises or over 3km against independent data such as laboratory results, to apply vaccination in at least some areas and assess anti-NSP tests or 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 they 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 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?

A professional diagnostic service headed by a dedicated highly trained specialist is my suggestion for avoiding the worst errors of the 2001 FMD UK outbreak in any other outbreak of infection including recurrence of FMD.

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A Professional Diagnostic Virology Service

Dr Ruth Watkins

Work prior to the FMD epidemic-preparation

Work once the outbreak of FMD has occurred