The Silent Invaders: Understanding 45 Plant and Animal Pathogens 2

26Lumpy Skin Disease

Lumpy Skin Disease

Lumpy skin disease is an infectious disease in cattle caused by a virus of the family Poxviridae, also known as the Neethling virus. The disease is characterized by a high fever, enlarged superficial lymph nodes, and multiple nodules (measuring 2-5 centimeters (1-2 in) in diameter) on the skin and mucous membranes (including those of the respiratory and gastrointestinal tracts). Infected cattle may also develop edematous swelling in their limbs and exhibit lameness.



27. Cats can get pimples. Feline acne are blackheads with inflammation on the cat's chin. Persian cats can get them on their faces and skin folds. Severe cases can damage the cat's health and appearance. Warm compresses, washing, and exfoliating with benzoyl peroxide may help.



28. A large downtown fire broke out in Boston during "The Great Epizootic Outbreak of 1872," a widespread outbreak of equine influenza, in part because firemen couldn't use horses to pull equipment since they were all sick with the virus. Instead, they had to pull all the equipment by hand.



29. After millions of trees in the USA died of Dutch elm disease in the 1980s, they were replaced by clonal males, which led to an increase in pollen and pollen-associated epidemics (allergies and asthma).



30. Mistletoe is a parasite that infects hundreds of species of trees and shrubs. Once it starts growing, it steals nutrients and water from the host, killing the portion of the branch it's on. Heavy infestations may kill off the entire host plant.



31Gypsy Moth Caterpillars

Gypsy Moth Caterpillars

Gypsy moth caterpillars infected by a species of baculovirus are hypnotized into climbing to the tops of trees to die, liquefy, and rain viral particles on the foliage below to infect others.



32. Frankincense and myrrh are derived from the hardened resin of desert-dwelling plants. The resin gets its aroma from antibacterial chemicals meant to protect the plant from infection.



33. The prion responsible for causing Chronic Wasting Disease (CWD) in ungulates (deer, elk, etc.) can lay dormant on plants and leaves for years until it's ingested. It can lay dormant in the dirt after the animal sheds saliva or other bodily fluids. If plants grow through that soil, even years later, it can harbor prions inside of it. Then, when the plant is eaten by another deer, the cycle starts all over again. Deer hunters are now being told to bring carcasses into a disposal facility after dressing the deer for meat so that they can be disposed of correctly. Even burning the carcass won't get rid of that pesky folded protein.



34. It's hypothesized that warm-bloodedness evolved in mammals and birds because it provided defense against fungal infections. Very few fungi can survive the body temperatures of warm-blooded animals. In contrast, fungal infections are a problem for insects, reptiles, and amphibians.



35. In various incidents, thousands of toads have swelled up with gas, grown to several times their normal size, then exploded for unknown reasons, propelling their innards as far as one meter away.



36Schistosomiasis in Snails

Schistosomiasis in Snails

Freshwater snails are one of the world's most deadly animals because they transmit the organism that causes schistosomiasis (aka bilharzia), which is, in and of itself, one of the deadliest parasites on the planet. In 2014, nearly 230 million people were infected, with 200,000 deaths each year.



37. Overfeeding fish can cause constipation and cause "Swim Bladder Disease," where fish turn upside down, thus creating "false death."



38. Green Muscle Disease is a condition that affects broiler chickens in which the breast muscle tissue necrotizes and turns green. This is most likely due to the limited space available to them during the growth phase, when the chickens are confined or otherwise restricted from spreading their wings. This causes a lack of blood supply to the muscles.



39. Researchers believe that the high-calorie foods of humans are to blame for the deformity known as "angel wing" in ducks. It renders them unable to fly, and it is only found in waterfowl fed by humans.



40. Unilateralis, or "zombie fungus," will hijack an ant's central nervous system and force the ant to climb a stalk of vegetation and anchor itself. The fungus then sprouts a stalk from the ant's head, releasing spores that infect ants below.



41Black Currants Disease

Black Currants Disease

Black currants were outlawed in America in 1911 due to spreading tree disease and impacting the timber industry. Thus, many Americans don't even know about this berry that is very popular in England.



42. Malaria-infected mosquitoes actually suffer fitness costs from carrying the malaria parasite. Studies have found that mosquitoes infected with malaria had about half as many offspring as noninfected mosquitoes, and another study showed that mosquitoes genetically manipulated to be resistant to the parasite performed better than normal mosquitoes when feeding on infected prey.



43. In 1950, a disease called myxomatosis was introduced to rabbits for population control in Australia. It wiped out 500,000,000 rabbits, giving them skin tumors and causing blindness, often killing them within 2 weeks. After that, calicivirus was introduced, which caused rabbit hemorrhagic disease.



44. Asian tigers (and other big cats) can become infected with the canine distemper virus, leading some of them to lose their fear of humans and wander into busy cities and towns. This could make endangered big cat species more vulnerable to poachers.



45. In the early 1980s, the US, Canada, and Mexico compelled Haiti to eradicate its pig population. This was meant to prevent the spread of African swine fever, but it devastated Haitian peasant wealth.