Veterinary Investigation Officers piecing the animal health puzzle together

Posted on May 29, 2019 by David Harwood

I worked as a veterinary investigation officer (VIO) for what is now referred to as APHA for 31 years - initially at the laboratory in Carmarthen and then latterly in Winchester. During this time, although my salary was being paid by government, I was undertaking my day to day tasks on behalf of three beneficiaries:

  • Firstly, the farmer submitting the carcase or samples for post mortem (PME) examination or laboratory testing wanting a diagnosis 
  • Secondly, the private vet who was investigating the case on behalf of their client
  • Thirdly, the government (devolved to its agency APHA)

The benefits to the farmer and their vet are obvious, but just how does government benefit?

‘Eyes and ears’ of the Minister

The role of a Veterinary Investigation Officer is often described as the “eyes and ears” of the Minister – constantly on the lookout for something unusual that may affect animal or public health. This may be a new and emerging problem, notifiable disease that may have been overlooked or not initially considered, welfare infringements, conditions that may have zoonotic/public health implications. This information is also used to provide monthly or yearly comparisons on the incidence of the more commonly encountered endemic diseases in the UK using Veterinary Investigation Diagnostic Analysis (VIDA) data collected on each submission received by those laboratories contributing throughout Great Britain.

Not just lab examinations and testing

However, not all surveillance information results from laboratory examination and testing and arriving at this information can be a lot more rewarding that you may think. Ultimately, making surveillance breakthroughs is all about communication and a fair bit of detective work – as the following two examples illustrate.

Being the first to identify a new disease

I was the first to report my suspicion of a particularly severe outbreak of foot lameness in a sheep flock in Sussex, which was eventually given the term Contagious Ovine Digital Dermatitis (CODD). I received a phone call from the veterinary practitioner wanting to discuss the outbreak, and we decided based on the information he gave, that a joint farm investigation visit may be a next step. I recall on arrival seeing 13 ewes that were recumbent around the building in a recently established flock of 580 in lamb ewes, many which had been purchased the previous year. Foot lesions were particularly severe, with some individual claws having been shed. The flock was very well managed, and there was no evidence of classical footrot. Despite several control measures being put in place, cases escalated rapidly. A letter to Vet Record was quickly published, asking for information on further cases, and full laboratory and epidemiological assessment resulted in this new disease being evaluated and a case definition developed.

Confirming Newcastle Disease

In a separate incident, I received a phone call from a private vet who had just completed a dairy cow fertility visit, when he was asked to look at some pheasants in pens on his drive out of the estate. He phoned to discuss the submission of affected birds that he described as having “twisted necks” and having difficulty moving around. As I was unable to rule out the possibility of notifiable disease by telephone, I asked him to remain on the estate, and immediately phoned the Reigate animal health office asking for an available veterinary officer to visit. Dead birds and culled affected birds were collected and sent for PME to Weybridge – and Newcastle Disease was confirmed.

As a result of post mortem examination and follow up, I have also reported and published about:

  • Acute pneumonia and pleurisy syndrome in adult dairy cows (presented at World Buiatrics Congress in Edinburgh).
  • Acute Post weaning Multisystemic Wasting Disease (PMWS) and Porcine Dermatitis Nephropathy Syndrome (PDNS) syndrome in pigs – with lesions initially suspicious of classical swine fever – but investigated by field investigation and many post mortem examinations, that lead to the disease being fully categorised, in collaboration with central veterinary laboratory at Weybridge.

And more unusual conditions such as nasal actinobacillosis in adult suckler cows, and malignant catarrhal fever in Kunekune pigs.

Collaboration is key

All these examples began on farm, and relied on good surveillance activity and collaboration between farm, private vet, and the APHA laboratory service. The number of Veterinary Investigation Centres (VICs) has been drastically reduced over the past few years, but new mechanisms for gathering this valuable post-mortem data have been developed via a number of differing APHA partner post-mortem providers. These must be maintained and enhanced as a matter of urgency.

Read BVA’s full position on veterinary scanning surveillance (animal health and disease monitoring), which sets out 25 recommendations for how the veterinary profession can work with UK Governments to optimise the existing surveillance network.

See more information about services available via the APHA Vet Gateway: ‘Surveillance and Diagnostics’ information and services page

David Harwood

Written by David Harwood

BVetMed MRCVS

Since retiring David has been working as a visiting Reader in Veterinary Field Pathology at the Surrey Vet School, and also lectures to undergraduate students at the RVC and Liverpool Vet School. He is a past president of the British Cattle Veterinary Association, past chairman of the Goat Veterinary Society (GVS), and Honorary Veterinarian to the British Goat Society. In 2018, David won the John Bleby Cup in recognition of his outstanding contribution to BVA Council.