Disease risks to the Galapagos - Birkbeck, University of ... · • Disease, biodiversity and...
Transcript of Disease risks to the Galapagos - Birkbeck, University of ... · • Disease, biodiversity and...
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