New Technologies for

Surveillance/Monitoring on

the Farm Prof. Alasdair JC Cook & Jimmy Wiseman

Dept of Veterinary Epidemiology & Public Health

School of Veterinary Medicine

University of Surrey

Sheep Health and Welfare Conference Wednesday 26th November 2014

Yarnfield Park Training and Conference Centre,

Stone, Staffordshire, ST15 0NL

Organised by the Sheep Health and Welfare Group (SHAWG).

• New approaches to delivery of surveillance

• Surveillance definition

• Purposes of surveillance

• Sources of information

• Users of information

• New technologies for detection and testing for disease

• Why do we need new tests?

• Desirable test characteristics

• LAMP tests

Outline

Introduction

• UK sheep population is approx 36 million sheep

• Ewe mortality estimated as 3% - 8% • loss of up to one million ewes/ year

• Estimated ewe replacement rates approx 20% • Lamb losses (birth – sale) 8% - 10% • Health & welfare issues include:

• Lameness • Parasites (internal & external) • Abortion & infertility • Mastitis • Production disease (metabolic/ nutritional etc)

• As Schmallenberg illustrated, sheep industry like other livestock sectors is susceptible to incursion of new diseases

“The systematic, continuous or repeated, measurement, collection, collation, analysis, interpretation and timely dissemination of animal health and welfare related data from defined populations. These data are then used to describe health hazard occurrence and to contribute to the planning, implementation, and evaluation of risk mitigation actions”.

Animal Health Surveillance Terminology Final Report from Pre-ICAHS Workshop

July 2013 (version 1.2)

http://www.fp7-risksur.eu/fileadmin/risksur/Documents/Publications/icahs-workshop-2011_surveillance_tewrminology_report_V1.2.pdf

Surveillance: Intelligence for Action

“The greatest challenge facing surveillance systems is awareness of the unexpected, recognising when things seem not quite right” MacLehose L, et al (2002) Science 295 2047-50

“Surveillance for the unknown requires a mindset different from surveillance of the known” Vourc’h G, et al (2006) EID 12 204-210

Surveillance purposes

• Scanning surveillance

• Demonstrate freedom from disease or infection

• Describe the level and distribution of specified diseases

• Describe changes in the health of the population or changes that may threaten the health of the population, this may include changes in the population at risk, changes in the occurrence of health indicators or of specified diseases

• Detect threats to human health

• Provide evidence in support of international trade

• Detect cases to facilitate control

Animal Health Surveillance and Farmed Livestock

• Stockperson observation includes all animals

• Veterinary practice records include individual clinical cases and may include herd parameters

• Herd / flock production data:

• Systematic info from many farms

• Laboratory data:

• Diagnostic; cases

• Screening; any animal

• Abattoir data – healthy

• Fallen Stock data – dead

• Movement records - transmission

The Surveillance Chain

Farmer

Private Vet Veterinary Specialist

Problems first spotted: 1. On farm.

2. In the habitat (wildlife).

Member of the public

Veterinary surgeons checking for disease:

1. On farm. 2. At markets.

3. At agricultural shows 4. At slaughterhouses.

Whole carcase

Whole carcases or other samples

submitted to: 1. APHA. 2. SAC.

3. Private Laboratories.

Source of first alert among 117 new or re-emerging threats detected by APHA Scanning Surveillance

How have emerging diseases been found?

ASSP 2011. Sustainable scanning surveillance in England and Wales: A report from the AHVLA Sustainable Surveillance Project. http://vla.defra.gov.uk/reports/docs/rep_assp_report1211.pdf

A pilot study on the value of fallen stock necropsy (Lovatt & Strugnell, 2013) aimed to investigate the diagnostic potential of this material and consider how such information might be applied to improve sheep health, welfare and productivity.

• Concluded that it is often possible to diagnose the cause of death without expensive diagnostic testing.

• Proposed that examination of fallen stock would lower the threshold for diagnostic investigation and thus improve best practice on UK sheep farms.

• For national disease surveillance and at the farm level, ongoing use of this concept may prove invaluable for livestock industries and the scope for its development is considerable.

Not a New Technology, But…

From Eamon Watson, APHA

Private Vets & Surveillance

• Primary requirement for laboratory diagnosis • Value determined by cost vs resolution of problem • Timeliness important

• Secondary interest in local/ national intelligence • What diseases are occurring now locally/ nationally? • Are there changes in nature of endemic disease? • Is this area free of conditions that are endemic nationally? • Are there emerging threats elsewhere that could occur her & now?

• “Altruistic” interest in surveillance for public good • What surveillance outputs are used by vets in practice? • What outputs could be used?

• Shared interest with Defra where new disease suspected • Subsidy to protect public interest not to enable producers to maximise production/ profit

• Added value as “CPD/ education” • Know what it is next time • Look out for new problems • Inform decisions on treatment/ prevention

What are the Most Important Sheep Diseases in the UK?

Scrapie

Caseous lymphadenitis

Sheep scab Salmonellosis

Cryptosporidiosis

Government Farmer

Parasitic gastroenteritis

Liver fluke

Clostridial disease

Orf

Lameness

Lice

Toxoplasmosis

Enzootic abortion

Campylobacteriosis

Maedi-Visna

• Well that can depend on who you ask!

• Varies between different regions.

• Depends on status and previous history of the flock.

• Owners of pedigree flocks may have different concerns.

• Notifiable and emerging disease threats usually take priority and, for the most part, this is justified, for economic and welfare reasons.

• However it should be remembered that actual losses due to endemic diseases far outweigh those from exotic or novel diseases.

• It is the improved control of these so-called, “Known-knowns,” that would allow major advances to be made.

• There is considerable scope to improve the control and management of endemic diseases in the livestock industry.

Endemic Disease, the Overlooked Enemy!

So…..What Can be Done?

Why do we need new veterinary tests??

• More rapid, sensitive and specific tests required appropriate to purpose (surveillance vs diagnosis) and of defined quality

• More cost effective tests required (especially with regard to sheep)

• Culture-less tests – Non-culturable/fastidious organisms.

• There is a clear need for reliable on-farm diagnostic tests that can be undertaken outside of the specialist laboratory – Pen-side tests

Demand for On-Farm Technologies

Sensitive Specific

Robust Rapid & cost

effective

Hallmarks of a Good Diagnostic Test

• Test hypotheses: • Is it a new threat? • Why?

• Emergence of new agent – what is it?

• Change in agent, host or environment

• New tools: • Cheap & rapid screening of the usual –

• PCR, BioSensor, LAMP

• Identification to sufficient level • Malditof

• Genomics

• Other omics

• Early detection of the unusual – the

New test methods

Disadvantage of Culture

Sample collection Microbiology – agar, biochemical tests

Result analysis

• Results Delivery

•Day 1 •Day 2 •Day 3 •Day 4

Loop mediated Isothermal amplification - LAMP

(LAMP) – an Alternative Method to PCR

LAMP

Specific

Sensitive

Quicker than culture

Isothermal

Inexpensive instrumentation

Portable

Low power consumption

Conventional PCR

Specific

Sensitive

Quicker than culture

Requires a thermocycler

Expensive instrumentation

Not portable

Higher power consumption

Options for Rapid Detection of the Target Organism

• Fluorometer

• Genie II

• 12v battery

• >1 kg

• Lateral flow device (LFD)

• Simple

• Unambiguous result

• Ideal for penside test

Rapid and Cost Effective

LAMP - Summary

Can detect as few as 4 copies of target gene

Sensitive

Validated against a panel of 30 different

bacteria species

Specific

Can be used with extract prepared

directly from clinical swabs

Robust

Positive result detectable in 7

minutes

Rapid & cost effective

This facilitates the efficacious and targeted treatment of infections,

thereby improving the health and welfare of patients and promoting the responsible and effective use of antibiotics.

PathPalTM

Rapid collection of PME data

• There are areas where surveillance information could potentially be collected in a cost-effective manner…

• Ante-mortem (health and welfare) and post-mortem (gross abnormalities) examinations are already conducted on all animals at the abattoir.

• It is a legal requirement that fallen stock are collected by a licensed collector.

• Large numbers of sheep carcases are therefore collected in such sites and this presents an opportunity for examination in order to establish the cause(s) of death.

• Not all diagnoses require confirmatory laboratory testing.

On the Other Hand…

• Many AHVLA regional centres have closed and the government funded surveillance budget has been markedly reduced.

• As a result, many holdings are no longer within the recommended 1 hour of travel to a post-mortem facility.

• The Independent Surveillance Advisory Group recommended that Surveillance activities should rely less on expensive expert post mortem examinations and more on gathering, analysing and integrating different data sources to identify trends and diseases.

• The need for new facilities offering an efficient post-mortem examination and sample collection service is clear.

…Post-Mortem Examination, A Changing Service?

Surveillance of animal health enables a healthy & sustainable food & farming industry and safeguards society from animal-related threats by the early identification of emerging disease and changes in patterns of endemic disease to inform timely action

All stakeholders have the opportunity to contribute to and benefit from participation:

• Livestock owners

• Integrated enterprises

• Vets in practice

• Food processors

• Retailers

• Consumers

• Government

A new vision for surveillance

• Surveillance is changing – this brings new opportunities as well as risks

• Key opportunities are

• A greater focus on endemic disease for non-Government stakeholders

• Integration of different sources of surveillance data to yield new information

• Key risk is a loss of system sensitivity if there were reduced participation by stakeholders and thus a potential for disintegration of existing systems

• Challenge – to engage all stakeholders more completely in surveillance

• Increasing availability of new & sophisticated diagnostics, like LAMP, will

• reduce price

• Increase sensitivity

• Reduce time to diagnosis

• & thus benefit surveillance as well as improve service to private vets & their clients

Key messages

Any Questions?

Further queries: alasdair.j.cook@surrey.ac.uk