Brief Outline of Why the Lessons Learned Inquiry might need to consider our research

 

 

Our research is ongoing and will hopefully produce some interim results, within the next few weeks, with the help of the Royal Society.

 

 

Lessons Learned Inquiry Terms of Reference:

To make recommendations for the way in which the Government should handle any future major animal disease outbreak, in light of the lessons identified from the handling of the 2001 FMD outbreak in GB.

 

 

To determine a practical, economic and successful control policy for the future we must first identify how FMD was transmitted in 2001 epidemic.

 

 

 

How is FMD transmitted?

The most common mechanism by which FMD is spread is the movement of infected animals and subsequent direct transmission of virus to susceptible animals in exhaled droplets and droplet nuclei. (Donaldson et al 2001).

 

 

 

How was disease transmitted in the UK 2001 FMD epidemic?

DEFRA (History of the epidemic)

Infected Animals 4.5%

Airborne 0.9%

Person and vehicle 5.0%

Under investigation 9.8%

Local (3 km) 78 % (mechanism not specified)

Other 1.8%

 

For the 2001 FMD UK epidemic we do not know by what mechanism nearly 88% of the infected premises became infected.

 

Until we know how the disease was spreading how can we determine a future control strategy.

 

 

 

 

 

Some Control Options

 

1.Slaughter- 3 km ring slaughter, contiguous slaughter?

2.Vaccination- 3 km ring vaccination? 10 km ring vaccination? Vaccinate to

live?

3.Complete slaughter of premises with clinically infected animals?

Non slaughter policy for sheep which are seropositive but virus negative?

4.Complete slaughter of premises where disease is detected, enforce good

biosecurity and vaccinate?

 

Only careful analysis of the current epidemic will determine which would be the best option.

 

Base data

 

DEFRA (JCC data analysis) Select committee link diagram

Confirmed cases 2026 304 cases were linked-before

movement ban?

 

 

(of which)

 

Laboratory negative 401

untested farms 301 Slaughter statistics (DCS database)

 

clinical neg. lab pos. 171 slaughter was incomplete on some

 

clinical pos. lab pos. 1153 farms, delayed by 1-5 days on others

took days , sometimes up to a week

to complete

 

There is no laboratory or clinical evidence to show that animals slaughtered for being contiguous to an infected premises were infected.*

Many dangerous contact animals were negative at laboratory test

 

 

*One particular case of contiguous spread has been identified by DEFRA , IP 1812.

This farm was contiguous to two IPs 1790 and 1791. On 1791 virus was thought to have been present for 4 to 6 weeks in the sheep before disease was transmitted to the cattle and then reported. Uninfected farms contiguous to unidentified pockets of disease cannot be considered in the same light as farms contiguous to premises where disease has been diagnosed swiftly.

 

 

Our research shows that:-

 

Most farm to farm transmission outside the hotspots occurred prior to the movement ban, or before disease was identified in the area.

 

Most farm to farm transmission in the hotspots was probably due to windborne spread ( due to delays in slaughter),unidentified pockets of disease present since the start of the epidemic, accidental veterinary contamination on patrol visits and direct stock to stock contact.

 

 

If we are right, then rapid slaughter, good biosecurity and possibly limited vaccination should be adequate to control future outbreaks without the need for a contiguous cull.