Cracking open or keeping a lid on? The Pandora s Box of human infectious disease risks associated with (intact) forests Kris Murray kris.murray@imperial.ac.uk @earthfluenza Hiral Shah Arran Hamlet Elizabeth Loh Jesus Olivero
Health + forests Ecosystem services Livelihoods Wellbeing Protection from disease? + Non-communicable disease Infectious disease Ecosystem disservices
Infectious diseases: the ultimate ecosystem disservice ~20% global burden of disease Plague - In 1347 killed ~1/3 of the European population Spanish Flu - In 1918 killed ~50-100 million people, caused symptoms in ~500 million HIV-AIDS - ~39 million deaths ~1.5 million deaths /yr ~35 million currently infected Malaria - ½ of all people who ever lived?
Global pathogen diversity / global biodiversity Most human infectious diseases originate and are shared with animals alpha beta (Murray et al., 2015; Start and Murray, submitted) (Start and Murray in review)
Land Use and ID
Land-use and disease: dynamic socio-ecological systems Wildlife to humans - HIV - Ebola - Rabies - SARS / MERS Environmental disturbance - YF / zika / dengue - Lyme - Hantavirus - Malaria +Domestic animals - Nipah - Avian Influenza (A) Jones et al. 2013
Land-use and disease Mechanisms: 1) Increasing contact 2) Perturbation of disease dynamics pathogen circulation changes Forest loss Changes in: composition abundance behaviour of reservoir species Increased transmission Intensification of animalhuman contacts (Murray and Daszak, 2013; Olivero et al., unpubl.)
Yellow fever Mosquito transmitted viral haemorrhagic fever Multiple animal hosts, multiple mosquito vectors Africa / South America (1,000s 50,000 deaths yr)
Yellow fever in South America Rapid endemic zone expansion over the last 20 years. Largest previous outbreak: 40 cases (1940) 2017: 777 cases 2018: similar primates Climate Land-use / change (Hamlet et al., unpubl) YF reports
Ebola Zoonotic viral haemorrhagic disease Largest outbreak prior to 2014: 425 cases (2000) 2013-2016: 28,616 cases (11,310 deaths) Olival & Hayman (2014) (Pigott et al., 2016)
Forest loss and Ebola virus disease Spatio-temporal pattern Forest loss 75.3 % -3.2 % 26.9 % 6 % -10.2 % 0.5 % Human population Virus presence 4.7 % Outbreaks along the limits rainforest biome significantly associated with forest losses in previous 2 years.
Exposure Forest monocultures Overall: 1.5 x Non-specific Ag: 1.6 x Rubber: 2.2 x Palm Oil: 3.3 x Malaria, worms, tick-borne pathogens Shah et al., unpubl)
Disease emergence: on the rise On the rise globally ~60% from animals ( zoonotic ) Animals Jones et al. 2008
Disease emergence: on the rise On the rise globally ~60% from animals ( zoonotic ) Mostly wildlife Wildlife Jones et al. 2008
Land-use change and disease Brunei Brunei Sarawak, Malaysia (Loh et al., 2015; Allen et al., 2017)
Gradient study ECOHEALTHNET 1942 2008 (Loh et al., unpubl)
Gradient study 1942 2008 Pontal do Paranapanema ECOHEALTHNET CONTINOUS LARGE SMALL MATRIX C1 C2 C3 L1 L2 L3 L4 S1 S2 S3 M1 M2 M3 M4 M5 (Loh et al., unpubl)
(Loh et al., unpubl) Diversity / prevalence
Recipe for disease risks High biodiversity pathogen pool Increasing contact with wildlife/vectors Growing populations, forest activities, hunting Changing environmental suitability for vectors deforestation /fragmentation / land-use change favouring disease vectors / hosts Novel contact with wildlife/vectors Remote, previously inaccessible Limited health and safety practices Limited health infrastructure
High biodiversity pathogen pool Novel contact with wildlife/vectors Remote, previously inaccessible Increasing contact with wildlife/vectors population growth, forest activities, hunting Improving environmental suitability for vectors Land-use change / deforestation / agriculture Limited health and safety practices Limited infrastructure
Cracking open / keeping the lid on Forests Services (incl. disease protection, carbon, biodiversity) Disservices (sources, exacerbated by disturbance) Services + Disservices = TEV Services: Enhance / preserve Disservices: confront, quantify avoid or mitigate? Co-management opportunities between environmental and public health agencies and stakeholders intact forests
Thanks! Dr Kris Murray kris.murray@imperial.ac.uk @earthfluenza Hiral Shah Arran Hamlet Elizabeth Loh Jesus Olivero