Sebastian Kennerknecht / Sunda Clouded Leopard (Neofelis diardi) male with cataract in his right eye in lowland rainforest, Tawau Hills Park, Sabah, Borneo, Malaysia

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed trees, Jasper National Park, Alberta, Canada

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed trees, Jasper National Park, Alberta, Canada

Jeff Foott / Ponderosa Pine (Pinus ponderosa) dead trees killed by Mountain Pine Beetle (Dendroctonus ponderosae), El Capitan, Yosemite National Park, California

Jeff Foott / Ponderosa Pine (Pinus ponderosa) dead tree, with pitch tube, killed by Mountain Pine Beetle (Dendroctonus ponderosae), Yosemite National Park, California

Jeff Foott / Ponderosa Pine (Pinus ponderosa) dead trees killed by Mountain Pine Beetle (Dendroctonus ponderosae), Yosemite National Park, California

Jeff Foott / Ponderosa Pine (Pinus ponderosa) dead trees killed by Mountain Pine Beetle (Dendroctonus ponderosae), Yosemite National Park, California

Jeff Foott / Ponderosa Pine (Pinus ponderosa) dead trees killed by Mountain Pine Beetle (Dendroctonus ponderosae), Yosemite National Park, California

Jeff Foott / Ponderosa Pine (Pinus ponderosa) dead trees killed by Mountain Pine Beetle (Dendroctonus ponderosae), Yosemite National Park, California

Paul Bertner / Braconid Wasp (Braconidae) cocoons attached to parasitized caterpillar, Udzungwa Mountains National Park, Tanzania

Paul Bertner / Leaf with virus, Cuc Phuong National Park, Vietnam

Paul Bertner / Leaf with virus, Antananarivo, Madagascar

Suzi Eszterhas / Common Wombat (Vombatus ursinus) with mange grazing on farm, Tasmania, Australia

Mark Carwardine / Orca (Orcinus orca), type one, with flaccid or collapsed dorsal fin, caused by stress, traumatic injury or ill-health, Snaefellsnes Peninsula, western Iceland

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed trees fueling forest fire, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) pair killed by resin, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed Lodgepole Pine (Pinus contorta), Grand Teton National Park, Wyoming

Jeff Foott / Lodgepole Pine (Pinus contorta) tree with pheromone packet to deter an attack from Mountain Pine Beetle (Dendroctonus ponderosae), Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed Whitebark Pine (Pinus albicaulis) trees, Bridger-Teton National Forest, Wyoming

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed Whitebark Pine (Pinus albicaulis) trees, Bridger-Teton National Forest, Wyoming

Jeff Foott / Campground being cleared of dead trees, killed by beetles, Rocky Mountain National Park, Colorado

Jeff Foott / Lodgepole Pine (Pinus contorta) forest killed by Mountain Pine Beetle (Dendroctonud ponderosae), Colorado

Jeff Foott / Lodgepole Pine (Pinus contorta) forest killed by Mountain Pine Beetle (Dendroctonud ponderosae), Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed Whitebark Pine (Pinus albicaulis) trees, Bridger-Bridger-Teton National Forest, Wyoming

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed trees, Rocky Mountain National Park, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed Lodgepole Pine (Pinus contorta) forest, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) pupa in Lodgepole Pine (Pinus contorta), Wyoming

Jeff Foott / Lodgepole Pine (Pinus contorta) pitch tubes, showing where Mountain Pine Beetle (Dendroctonus ponderosae) attacked tree, and tree tried to pitch it out, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) larvae under tree bark, Grand Teton National Park, Wyoming

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) larvae under tree bark, Grand Teton National Park, Wyoming

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) larva under tree bark, Grand Teton National Park, Wyoming

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) in tunnel under bark, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) in tunnel under bark, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) successfully 'pitched out' by tree defense, Grand Teton National Park, Wyoming

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed Lodgepole Pine (Pinus contorta) forest with some healthy trees, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed tree, Rocky Mountain National Park, Colorado

Jeff Foott / Mountain Pine Beetle (Dendroctonus ponderosae) killed trees, Rocky Mountain National Park, Colorado

Nick Upton / Seal hospital where injured Grey seal pups (Halichoerus grypus) are treated for injuries and illness after being rescued, Cornish Seal Sanctuary, Gweek, Cornwall, UK, January.

Kevin Schafer / Ochre Sea Star (Pisaster ochraceus) infected with Sea Star Wasting Disease, Olympic Peninsula, Washington

Suzi Eszterhas / Koala (Phascolarctos cinereus) being treated for chlamydia, Port Macquerie, New South Wales, Australia

Roland Seitre / Orca (Orcinus orca) aquarium captive male exhibiting flaccid fin syndrome, Spain

D. Parer & E. Parer-Cook / Common Wombat (Vombatus ursinus) with sarcoptic skin mange, which will eventually kill it, southeastern Australia

Tui De Roy / Small Ground-Finch (Geospiza fuliginosa) with an advanced case of introduced avian pox disease, Academy Bay, Santa Cruz Island, Ecuador

Suzi Eszterhas / Koala (Phascolarctos cinereus) sick with KoRv retrovirus being held by Hospital Manager Patricia Swift, Currumbin Wildlife Hospital, Queensland, Australia

Alex Mustard / Coho salmon (Oncorhynchus kisutch) migrating upstream in the Adams River, British Columbia, Canada.The stresses of the migration take their toll on the health of these fish, and this one has lots of f...

Pete Oxford / Ebola warning sign, Odzala-Kokoua National Park, Democratic Republic of the Congo

Suzi Eszterhas / Koala (Phascolarctos cinereus) sick with KoRV retrovirus climbing an artificial tree near hospital manager Patricia Swift, Currumbin Wildlife Hospital, Queensland, Australia

Suzi Eszterhas / Koala (Phascolarctos cinereus) koala with KoRv retrovirus being examined by hospital manager Patricia Swift, Currumbin Wildlife Hospital, Queensland, Australia

Suzi Eszterhas / Koala (Phascolarctos cinereus) female named Sue sick with chlamydia being fed by volunteer Gabriella Rivett, Koala Hospital, Port Macquarie, Australia

Suzi Eszterhas / Koala (Phascolarctos cinereus) orphaned joey named Josie with supervisor Cheyne Flanagan and volunteer Joy Barber, Koala Hospital, Port Macquarie, Australia

Suzi Eszterhas / Koala (Phascolarctos cinereus) with chlamydia being treated by hospital supervisor Cheyne Flanagan (left), Koala Hospital, Port Macquarie, Australia

Cyril Ruoso / Ring-tailed Lemur (Lemur catta) mother and baby showing hair loss (alopecia) due to poisoning from Central American introduced Lead Tree (Leucaena leucocephala) vulnerable, Berenty Private Reserve, Ma...

Cyril Ruoso / Chimpanzee (Pan troglodytes) sick baby with a big belly, Gabon

Juergen Freund / Stella Chiu Freund holds a staving green turtle (Chelonia mydas) overgrown with algae and barnacles. With the loss of seagrass beds due to floods and cyclone damage, turtles are starving all along the...

Juergen Freund / Dr. Leo Foyle holds on to green turtle (Chelonia mydas) they named Roxy. Roxy has a severe case of fibropapillomas and has been in James Cook University lab for many weeks undergoing observation and c...

Juergen Freund / James Cook University vet and student hold on to green turtle (Chelonia mydas) they named Roxy with severe case of fibropapillomas. Townsville, Queensland, Australia, August 2011

Juergen Freund / James Cook University vet and student hold on to green turtle (Chelonia mydas) they named Roxy with severe case of fibropapillomas.Townsville, Queensland, Australia, August 2011

Roland Seitre / Hoffmann's Two-toed Sloth (Choloepus hoffmanni) veterinarians treating orphan with mange, Aviarios Sloth Sanctuary, Costa Rica

Jabruson / Grey cheeked mangabey (Lophocebus albigena) captive youngster about to be picked up by gloved hand, to be taken indoors for the night. It's mother was shot by hunters so now this animal is kept as a p...

Jabruson / Grey Cheeked Managabey (Lophocebus albigena) young being held captive by child within village, its mother was shot by a hunter, meaning it will be kept as a pet and play-thing until old enough to be e...

Jabruson / Putty nosed monkey (Cercopithecus nictitans nictitans) young female climbing village house wall in boredom, tied to a heavy old vehicle engine part is held captive in a village close to the forest. Th...

Jabruson / Watched by a large group of children, a Putty nosed monkey (Cercopithecus nictitans nictitans) young female tied to a heavy old vehicle engine part is joined by a young captive free-ranging male Grey-...

Jabruson / Putty nosed monkey (Cercopithecus nictitans nictitans) young female tied to a heavy old vehicle engine part is held captive in a village close to the forest. The mother was shot by a hunter, meaning t...

Jabruson / Under the watchful direction of her owner, a Putty nosed monkey (Cercopithecus nictitans nictitans) young female tied to a heavy old vehicle engine part is joined by a young captive free-ranging male...

Jabruson / Putty nosed monkey (Cercopithecus nictitans nictitans) young female tied to a heavy old vehicle engine part is held captive in a village close to the forest. The mother was shot by a hunter, meaning t...

Will Watson / Horse Chestnut (Aesculus hippocastanum) leaves with Leaf minor (Cameraria ohridella) Herefordshire, UK November 2012

Loic Poidevin / European Rabbit (Oryctolagus cuniculus) suffering from myxomatosis. West France, June.

Sumio Harada / Gray Wolf (Canis lupus) diseased with scabies, Yellowstone National Park, Wyoming

Dave Bevan / Rhododendron (Rhododendron sp.) flower spikes showing symptoms of Sudden Oak Death (Phytophthora kernoviae), a fungus-like pathogen.

Anup Shah / Hippopotamus (Hippopotamus amphibius) juvenile with pink skin from rare disease Leucism with resting group, Masai Mara National Reserve, Kenya, September

Anup Shah / Hippopotamus (Hippopotamus amphibius) juvenile with pink skin from rare disease Leucism with resting group, Masai Mara National Reserve, Kenya, September

Dave Watts / Tasmanian Devil (Sarcophilus harrisii) scientists working on devil with cancer (DFTD) Devil Facial Tumour Disease, Cradle Mountain, Tasmania, Australia

Dave Watts / Tasmanian Devil (Sarcophilus harrisii) being released following trapping program for DFTD - Devil Facial Tumour Disease, Cradle Mountain, Tasmania, Australia

Dave Watts / Tasmanian Devil (Sarcophilus harrisii) being released following trapping program for DFTD - Devil Facial Tumour Disease, Cradle Mountain, Tasmania, Australia

Dave Watts / Tasmanian Devil (Sarcophilus harrisii) euthanized by a vet following serious devil cancer - Devil facial tumour disease (DFTD) Cradle Mountain, Tasmania

Dave Watts / Tasmanian Devil (Sarcophilus harrisii) captive creature with facial cancer - Devil facial tumour disease (DFTD) Cradle Mountain, Tasmania

Dave Watts / Tasmanian Devil (Sarcophilus harrisii) captive creature with cancer - Devil facial tumour disease (DFTD) Cradle Mountain, Tasmania

Pete Oxford / Cape Buffalo (Syncerus caffer) veterinary fence to control foot and mouth disease transmission, Moremi Game Reserve, Okavango Delta, Botswana

Jeff Rotman / El Molo child suffering from rickets, caused by a diet consisting primarily of fish. El Molo children suffer from vitamin D deficiency, which develops into the nutritional disease causing deformities...

Daniel Heuclin / Removing Guinea worm (Dracunculus medinensis) from foot - parasitic nematode that causes guinea worm disease in people, Benin.

Daniel Heuclin / Removing Guinea worm (Dracunculus medinensis) from foot of african - parasitic nematode that causes guinea worm disease in people, Benin.

Pete Oxford / Huaorani Indian with splayed feet. Several of the Huaorani have these feet problems and there are some with 6 toes on each foot. Bameno Community, Yasuni National Park, Ecuador, May 2007.

Tony Phelps / Bite from Cape Cobra snake (Naja nivea) on human limb,48 hours after the bite, showng blistering and swelling. Western Cape, South Africa. Model released

Tony Phelps / Bite from Cape Cobra snake (Naja nivea) showing blistering and swelling on human hand 48 hours after the bite. South Africa. Model released

Yva Momatiuk & John Eastcott / Sockeye Salmon (Oncorhynchus nerka) female resting against rocks with skin discolored by fungus and infection, Adams River, Roderick Haig-Brown Provincial Park, British Columbia, Canada

Pete Oxford / Small Tree-Finch (Camarhynchus parvulus) studied for avian pox showing pox growth on foot, highlands of Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Medium Ground Finch (Geospiza fortis) getting bill length measured, part of avian pox research, Puerto Ayora, Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Medium Ground Finch (Geospiza fortis) getting blood drawn, part avian pox research, Puerto Ayora, Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Medium Ground Finch (Geospiza fortis) getting banded, part of avian pox research, Puerto Ayora, Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Medium Ground Finch (Geospiza fortis) caught in mist net to be studied for avian pox, Puerto Ayora, Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Medium Ground Finch (Geospiza fortis) caught in mist net to be studied for avian pox, Puerto Ayora, Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Small Tree-Finch (Camarhynchus parvulus) studied for avian pox showing leg bands, highlands of Santa Cruz Island, Galapagos Islands, Ecuador

Pete Oxford / Small Tree-Finch (Camarhynchus parvulus) studied for avian pox having blood drawn, highlands of Santa Cruz Island, Galapagos Islands, Ecuador

Tui De Roy / Small Ground-Finch (Geospiza fuliginosa) affected by introduced avian pox virus, Galapagos Islands, Ecuador

Pete Oxford / European Rabbit (Oryctolagus cuniculus) infected with myxomatosis, a viral infection that causes blindness and possibly death, Sierra de Andujar Natural Park, Andalusia, Spain

Albert Lleal / Sewage and shacks in Dhaka slum, Bangladesh