The Benefits of Costs of Biosecurity: Optimal Quarantine and Surveillance

Tom Kompas and R. Quentin GraftonCrawford School of Economics and Government

Kevin Fox (UNSW)

CERF Project/CERF Hub Presentation 20 May 2008

Acknowledgement: DEWHA

Motivation

• Combined with border quarantine measures, local surveillance programs provide an essential protection against the incursion and spread of dangerous exotic diseases and pests.

• However quarantine and surveillance programs also impose costs (border quarantine and surveillance expenditures), along with the costs of disease management and eradication.

• Problem: find the optimal amount of border quarantine and surveillance activities (or expenditures) to protect plant and animal health, as well as the environment.

Research Design: Optimal Surveillance

• Benefit: Surveillance ensures ‘early detection’, lowering economic and environmental losses and pest/disease management costs.

• Tradeoff: The more early the detection the more expensive the surveillance measure.

• Objective: minimize:

• Economic losses (plant, animal, the environment)

• Eradication and management costs of the pest/disease incursion

• Surveillance expenditures (e.g. monitoring, the cost of setting and monitoring traps, etc.)

Pest/Disease Incursion and Spread

Nmax

Rmax

X

N0 O T(X) T(Rmax)) T

Infested area

Maximum area

Natural detection point

Choice of early detection

time

Surveillance Expenditure Function

m

m

( )( , )

( 1)mE R X

E XR X

Em

E*

O X* maxR X

E(X)

=0

Example: Papua Fruit Fly in Australia

• PPF attacks fruit (e.g. apples) and in early stages is difficult to detect by inspection.

• Largest risk of entry: via the Torres Strait Islands and at ports of entry.

• Current surveillance grid: 1 trap for every 6,200 km2 , 1,878 traps in total, Exp = $1,380,000 (including the programs fixed costs).

• 1995 outbreak in QLD: $43m in eradication and management costs over a 13 month period.

Optimal Surveillance Grid and Expenditures (PPF)

Optimal: one trap per 2,000 km2 and E*(c) = $3m (AUS)

Current: $1.38m: Current surveillance grid: 6,200 km2

Future CERF work

• Apply to several Red Imported Fire Ants and Yellow Crazy Ants in Australia.

• Measure and include the benefits of biodiversity. • Construct spatial models of pest and disease

surveillance.