Disease risks to the GalapagosU d di d Q if iUnderstanding and Quantifying Current and Future ThreatsCurrent and Future Threats

Simon Goodman, Gillian Eastwood, Arnaud Bataille, Laura Kramer, Marilyn Cruz, Leandro Patino, Virna

Cedeno, Andrew Cunningham 

OverviewOverview

• Disease biodiversity and island ecosystemsDisease, biodiversity and island ecosystems

• Why Galapagos?

• Overview of the development of disease ecology• Overview of the development of disease ecology research in Galapagos

St t i f d t di di i k• Strategies for understanding disease risks

• Disease risks in Galapagos – WNV case study

• Moving from risk analysis to mitigation measures

• Sustainable biosecurity for Galapagos

Map from Morens et al. 2004, Nature 430: 242‐249.

Biosecurity and the conservation of l disland ecosystems

• Islands are hotspots for species endemism due to p pgeographic isolation and evolutionary radiations by relatively small numbers of colonising speciesI l d t hi hl tibl t d d ti• Island ecosystems are highly susceptible to degradation due to introduced and invasive species

• In the case of disease, island ecosystems often haveIn the case of disease, island ecosystems often have depauperate pathogen communities, and  species may be immunologically naive to pathogen families not present historically leading to increased susceptibilitypresent historically, leading to increased susceptibility and mortality for incoming diseases

Hawaiian Honey CreepersHawaiian Honey Creepers

• Honeycreepers are paradigm for evolutionary radiations

• 19 extant and 11 extinct species

• Also a paradigm for extinction by disease!

• Combination of habitat modification with introduction of Culexmosquitoes, avian malaria and avian pox virus

Why Galapagos?y p g

Why Galapagos?Why Galapagos?

• High endemism rates, iconic speciesg , p• Key role in the development of scientific thinking through the influence of Galapagos species on Charles Darwin and the theory of evolution byCharles Darwin and the theory of evolution by natural selection

• Key economic driver and source of income forKey economic driver and source of income for Ecuador

• Sustainability of Galapagos ecosystem is at risk f i i i i i f hi i lfrom invasive species arising from historical settlement, and current rapid economic development and population growthp p p g

Growth in tourism and invasive insect i i d ispecies introduction

Disease ecology research in GalapagosDisease ecology research in Galapagos

• Disease threats to Galapagos avifauna firstDisease threats to Galapagos avifauna first highlighted in 2000 following a workshop at Cornell UniversityCornell University

• However, essentially a complete absence of knowledge about pathogens and wildlifeknowledge about pathogens and wildlife disease issues in the Galapagos ecosystem

E d i h i i h d l• Ecuadorian authorities had no clear strategy for dealing with wildlife disease in Galapagos

Disease ecology research in GalapagosDisease ecology research in Galapagos

• Galapagos Genetics, Epidemiology and Pathology Ga apagos Ge et cs, p de o ogy a d at o ogylaboratory project initiated in 2003– Zoological Society of London– University of Leeds– Galapagos National Park ServiceU i i f G il– University of Guayaquil

– Concepto Azul

• UK government Darwin Initiative funding from• UK government Darwin Initiative funding from 2003‐2008

• NERC & Marie‐Curie doctoral training grants• NERC & Marie‐Curie doctoral training grants

Disease ecology research in GalapagosDisease ecology research in Galapagos

• Establish human and physical capacity for wildlife p y p ydisease research and surveillance in the Galapagos national park service

• Conduct baseline and directed disease• Conduct baseline and directed disease investigations and surveillance in order to make informed, science based decisions on disease issues

• Support education and awareness for decision makers and local populationmakers and local population

• Support development of policy and mitigation measures based on research outputsp

Disease threats to Galapagos fauna

Introduced & colonising species

Emerging diseases

Spill over fromSpill over from domestic animals

IntroducedIntroduced vectors Native disease 

and vectors

Some of our research topics

Galapagos tortoiseGalapagos mosquito ecology & genetics

CDV epidemiology in sea lions & dogsGalapagos tortoise 

health & mortalityecology & genetics sea lions & dogs

Development of assays for pathogen surveillance

Baseline pathogen surveys

Disease risk assessments (WNV)

Understanding & quantifying disease hthreats

• Introduction riskH i i– Horizon scanning

– Pathways

• Establishment– Environmental & ecological factors

• Impact– Host & vector propertiesp p

West Nile VirusWest Nile Virus is current major EID of birds with implications for human health

• First identified in Africa in 1937

• Causes meningitis like symptoms in a small proportion of human cases

• Flavivirus (RNA) virus, transmitted byFlavivirus (RNA) virus, transmitted by mosquitoes (and other biting arthropods)

• Main reservoir is birds (detected in at least 138 species), where it causes range of effects, e.g. p ), g , gmost birds typically have low mortality, while mostly lethal in corvids

• Has caused massive declines in corvidpopulations in USA

• Now in South America, concerns over transmission to Galapagos & Hawaii

~ 40% mortality

Spread of West Nile Virus in the USA (bird cases)

20012000

2002 2003

Pre‐emptive risk assessment for WNV i d i lintroduction to Galapagos

Pathway Number arriving in

Galápagos/year

Infectiousness x Duration

Infectious host or mosquito-days/year

Mosquito by1. Wind2. Air cargo3. Sea cargo

<10-3

(1910)(1.65)(9750)(0.00036)

(0.0098)(0.22)(15)(0.0098)(0.22)(15)(0.0098)(0.22)(15)

<1x10-6

101.7 (8.3-272.9)0.11 (0.00-0.35)g ( )( ) ( )( )( ) ( )

4. Human 90,533 0 05. Human transportedvertebrates (day-old chickens)

- - Low risk under current regulations?chickens) regulations?

6. Migratory birds (Shorebirds)

12,500 (0.00125/5)(1.75) 5.5 (2.2-11.8)

Predicting pathogen introduction: West Nile Virus Spread to Galapagos. Kilpatrick, et al. 2006 Conservation Biology.

Parameterising future risk assessment modelsmodels

• What do we need to know?– Introduction risk

• Pathways to the islands & (effective) rates for each route• Galapagos specific rates

– Establishmenth h• Contact with hosts & vectors

• Competency of vectors• Distribution of appropriate habitat/hosts for disease agents, dependence on climatic factors and variationp

• Intra/inter island dissemination rates and routes– Impact

• Susceptibility, morbidity and mortality of host species• Host life history and ecology, interactions with other species

• Modification of risks due to human activities and socioeconomic factors

From risk analysis to mitigation d lmeasures and policy 

• Mitigation measuresMitigation measures need to be science based

• Research informs efficient targets for mitigation

• Primarily instigated by local stakeholders and agencies

Creating sustainable biosecurity for lGalapagos

• Ecuadorian ledEcuadorian led• Preemptive rather reactive focus• Scientific capacity• Scientific capacity • Research infrastructureI tit ti l t bilit• Institutional stability

• Clarity of Institutional roles & coordination• Stable and sustainable funding, administration and oversight