Pathogen management modelling presentation given at the APEG 201 conference held at Cefas.

1. Pathogen management
and modelling
Nick Taylor
Population
Ecologist/Epidemiological
Modeller

2. Disease monitoring and emergence
• Fish Health Inspectorate:
– 10 field inspectors
– Visit 700+ APB’s per annum
– Early identification of
problems
– Big picture perspective
• Epidemiology and risk
assessment:
– ID potential threats
– Assess the risk posed
– Suggest mitigation measures

3. Emerging diseases

4. Pathogen testing
• Reference lab (EU, national, OIE) for:
– Viral haemorrhagic septicaemia
– Infectious haematpoietic necrosis
– Bacterial kidney disease
– Gyrodactylus salaris
– Spring viraemia of carp
– Marteiliosis
– Bonamiasis
– Infectious pancreatic necrosis
– Crayfish plague.
• Pathogen culture, PCR, antigen ELISA
and antibody testing.

5. Field studies
• Assess distribution and
scale.
• Study pathogen life-cycles
and dynamics in the real
world.
• Conduct classical
epidemiological studies:
 Cross-sectional
 Cohort
 Case-control
• Identify risk factors.

6. Complex data and statistical tools

7. Pathogen life-cycles
1 2 3 4 5 6
4.7
4.4
4.1
3.8
3.5
3.2
Length (mm)
2.9
2.6 7
2.3
2
1.7
1.4
8
1.1
0.8
May-02 Jun-02 Jul-02 Aug-02 Sep-02 Oct-02 Nov-02 Dec-02 Jan-03 Feb-03 Mar-03 Apr-03 May-03

8. Experimental studies

9. Pathogen challenge studies

10. Efficacy against pathogen
600
c1
550
c2
500 c3
t1
450 t2
t3
400
350
Abundance
300
250
200
150
100
50
0
1 2 3 4 5 6 7

11. Benefit to host

12. Environmental impact

13. Disease modelling

14. Optimal application and control
policies
10°C 15°C 20°C 25°C
pH 6.1 1 1 1 1
pH 6.4 1 1 1 2
pH 6.7 1 1 2 2
pH 7.0 1 2 2 3
pH 7.3 1 1 2 2
pH 7.6 1 1 1 2
pH 7.9 1 1 1 1

15. Summary
• What’s the problems.
• Extent and severity.
• How to test for it.
• What drives it.
• What’s its life-cycle.
• Effective treatments.
• How to manage.