Humans Can Catch Disease and Parasites From Infected Pest Animals
A Zoonotic Disease is a disease that may be passed between animals and humans. This most commonly occurs between birds, rodents, and other pest animals. Below is a partial list of such zoonotic diseases, illustrating part of the reason it’s so important to keep pest animals away from humans.
Birds and Their Droppings Can Carry Over 60 Transmissible Diseases
Bird infestations can prove more of a hazard than most people realize, as many carry more than 60 transmissible diseases* – this list continues to grow and is not exhaustive of all possible risks posed by pest animals.
Allergic Alveolitus occurs when humans inhale particles of bird dander in the air. Also known as “Pigeon Lung Disease,” this affects the alveoli if the lungs, decreasing the lungs’ ability to function & making it difficult to breathe.
Avian Influenza, also known as “The Bird Flu” is the H5N1 virus which is transmitted through the fecal matter of infected birds. This serious disease is able to live in objects such as bird feeders, baths, and houses, as well as in birds themselves. This disease is well-known for being deadly in humans, causing more severe symptoms than typical flu viruses including high fever, cough, respiratory difficulties, and muscle aches.
Avian Tuberculosis is caused by inhaling microscopic organisms found in the feces of birds. Potentially fatal, this disease is difficult to treat and symptoms include weight loss, swollen stomach, diarrhea, and impaired breathing.
Campylobacteriosis causes gastrointestial distress, usually transmitted through food and water that’s been contaminated by bird fecal matter. Symptoms include diarrhea, weight loss, and lethargy.
Candidiasis is a yeast or fungus infection spread by pigeons. The disease affects the intestines, mouth, skin, urogenital tract, and the respiratory system.
Cryptococcosis is caused by yeast found in the intestinal tract of pigeons and starlings, usually passed by ingestion of infected fecal matter. This illness begins as a pulmonary disease & can advance to affect the central nervous system.
E.coli is generally spread via fecal contamination of food. Birds frequently peck on cow manure, which is one place where E.coli 0157:H7 originates. Infected birds are unaffected but spread the bacteria into food and water supplies.
Erysipeloid is passed by direct contact between humans and birds. Broken skin is affected, which changes from red to blue-red, and the infection can spread to joints.
Giardiasis is caused by an intestinal parasite Giardia found in contaminated food, causing diarrhea, weight loss, bloating, nausea, vomiting, and dehydration.
Histoplasmosis or “Ohio River Valley Fever” is transmitted when humans inhale the Histoplasma capsulatum fungus that grows in dried bird and bat droppings. It is an extremely serious respiratory disease that can prove fatal, especially in those with compromised immune systems, including children.
Newcastle Disease (or “Avian Pneumoencephalitis“) is passed orally through food contaminated by infected bird fecal matter. The Newcastle disease virus causes flu-like symptoms, neurological dysfunction, seizures, conjunctivitis, and respiratory problems.
Pasteurellosis usually occurs when humans are bitten or scratched by birds infected by Pasteurella multocida organisms, though in some cases caused by inhalation via respiratory droplets. Scratches may become red and infected, while respiratory infection can result in bronchitis, pneumonia, or septicemia.
Psittacosis also known as “Parrot Fever,” “Ornithosis,” or “Chlamydiosis” occurs when the C.psittaci bacterium passes to humans via inhalation, contact, or ingestion. This potentially lethal disease causes flu-like symptoms in humans and can quickly escalate to pneumonia.
Q Fever is caused by Coxiella burnetii, a gram-negative pleomorphic bacillus that is passed in the feces of infected birds as well as other animals and ticks. Symptoms in humans include fever, headache, pneumonitis, and photophobia.
Salmonellosis can be traced to the droppings of pigeons, starlings and sparrows. Most often dried waste bacteria is sucked through contaminated air conditioners or vents, contaminating the food and cooking surfaces of restaurants, food processing plants, and homes.
Sarcocystis is a parasytic infection transmitted by birds as well as contaminated water (though this is not yet certain), and is also carried by rats. Symptoms in infected humans include nausea, diarrhea, and abdominal pain. Usually only lasting 48 hours or less, this infection can be life-threatening, especially to the elderly and those with compromised immune systems.
St. Louis Encephalitis is spread by mosquitoes which have fed on pigeons, house sparrows and finches carrying the Group B virus. The nervous system becomes inflamed, usually causing fever, headache, & drowsiness. It can later result in coma, paralysis, or death. It is especially fatal to persons over age 60.
West Nile Virus (“West Nile Fever” or “West Nice Encephalitis“) is spread by mosquitos that have fed on infected wild birds. A potentially life-threatening infection that can cause weeks or months of illness.
Birds are Also Associated With Over 50 Kinds of Ectoparasites
Several bird ectoparasites** (a parasite that lives on the skin/exterior of a host) can easily transfer to humans, including:
Bed bugs (Cimex lectularius) are often found on pigeons, starlings, and house sparrows. Bed bugs draw blood from hosts including humans, and can consume up to 5 times their weight in blood. Infestations are common, especially in cities.
Chicken mites (Dermanyssus gallinae) are known carriers of encephalitis and may also cause fowl mite dermatitis & acariasis. Chicken mites primarily feed on the blood of birds, but will often bite humans. They are commonly found on pigeons, starlings, and house sparrows.
Fleas (Ceratophyllus gallinae & Dasypsyllus gallinulae; “the bird flea”) spend little time on bird hosts, but often infest nests and can easily transfer onto pets or humans. Bird fleas are a concen in hen houses and battery cages, and are known to rapidly reproduce in bird nests.
Fungi grows on decomposing skin (cellulose) & feathers (keratinophilic) of birds themselves, shielded in the plumage barrier. Fungi also grows on bird nests and in bird droppings, and are associated with many of the inhalation-contracted diseases noted above.
Ticks which bite/embed themselves onto humans, including larvae, nymphs and adults. Ticks can transfer onto surfaces via bird feeders or wherever birds land. Deer ticks notably carry and transmit Lyme Disease, as well as other diseases humans can contract.
Lice of all kinds enjoy the barrier feathers create, some feeding on the feathers themselves. A variety of such lice also enjoy human skin and hair.
Yellow mealworms are likely the most common beetle parasites of people in the United States, often infesting homes and biting humans in their larval form. These pests commonly live in pigeon nests and chicken coops, but their eggs may be passed on by carrier birds. These larvae often seek out human food sources, such as breakfast cereals, and if ingested may cause symptoms including intestinal canthariasis and hymenolespiasis.
Birds Nests Provide Homes to Insects
In addition to diseases and ectoparasites, nests provide ideal shelter for many insects, including but not limited to:
Booklice (or Psocids) are wingless and very tiny bugs that feed on fungi within bird nests. Booklice do not bite or transmit disease, but can be annoying in large numbers.
Carpet Beetles, also known as Skin Beetles, Dermestidae Beetles, Larder Beetles, Hide Beetles, Leather Beetles, and Khapra Beetles, are often found inside homes. There are around 500-700 species worldwide. These beetles commonly breed inside bird nests, feeding on dry animal matter, fungus, feathers, dried insects & natural fibers, including clothing.
Cloth Moths (Tineola bisselliella) also known as common cloth moths, webbing cloths moth, or clothing moth, these pests often breed inside bird nests. When infesting a home, they feed on clothing & natural fibers, especially wool and silk. Common closet pests, these moths are highly undesirable.
Spider Beetles (Mezium americanum, Ptinus fur, & Gibbium aequinoctiale) are small beetles that resemble spiders or ticks, commonly found in bird nests. Spider beetles feed off bird droppings and are most commonly found in homes when feeding on grain in pantries or sources in attics. In large numbers they can become very difficult to get rid of; the most successful management method is to get rid of the food source – sometimes unseen, such as a bird or rodent nest located on/inside the building structure.
Rodents & Bats Carry A Variety of Transmissible Diseases
Campylobacter causes gastrointestial distress, usually transmitted through food and water that’s been contaminated by bird fecal matter. Symptoms include diarrhea, weight loss, and lethargy.
Hantavirus Pulmonary Syndrome (HPS) is a serious respiratory disease, caught by humans from infected rodents. If left unchecked, the pulmonary illness can rapidly prove fatal. Rodent infestation inside and outside a home is the most common cause of hantavirus exposure. Healthy humans as well as those with compromised immune systems are at risk. It is not normally transmitted person to person, but rather rodent to person. Common carriers of the hantavirus include the deer mouse, white-footed mouse, rice rat, and cotton rat.
Leptospirosis can be easily transmitted through inhalation or contact with infect animals’ tissue or urine via broken skin and mucous membranes. The disease mimics flu-like symptoms but can also lead to kidney failure, pulminary problems, and encephalitis.
Lymphocytic Choriomeningitis Virus infects humans via wild mice, by inhalation or direct contact with tissues or fluids from infected animals. Symptoms include fever, headache, myalgia, and malaise, and can escalate to meninoencephalitis, lymphadeopathy, and affect the neurological system.
Rabies are commonly carried by bats and other warm-blooded mammals such as raccoons, skunks, and foxes. Rabies is a viral disease that causes inflammation in the brain and can prove fatal – it is an extremely serious and contageous disease that requires immediate medical attention.
Rat-Bite Fever is generally spread to humans through rodent bites, symptoms include flu-like symptoms such as fever, chills, headache, and muscle pain, as well as a rash, abscesses, pneumonia, painful joints, and more serious conditions.
Rodentolepsis occurs when the tapeworm Rodentolepsis nana is ingested as eggs by humans, generally due to exposure with rodent waste. Symptoms include abdominal pain, enteritis, headache, and decreased appetite. Carriers of the tapeworm can also include cockroaches, beetles, and fleas.
Salmonellosis can be traced to the droppings of pigeons, starlings and sparrows. Most often dried waste bacteria is sucked through contaminated air conditioners or vents, contaminating the food & cooking surfaces of restaurants, food processing plants, and homes.
Tuberculosis (TB) is a lung disease caused by Mycobacterium tuberculosis which typically attacks the lungs, but can attack any part of the body including the spine, kidneys, and brain. TB can prove fatal if not treated, and was one of the leading causes of death in the United States.
* “Birds And Their Droppings Can Carry Over 60 Diseases.” Medical News Today. January 25, 2007. http://www.medicalnewstoday.com/releases/61646.php
** Clayton, Dale H. et al. “How Birds Combat Ectoparasites” The Open Ornithology Journal, 2010, 3, 41-71. http://darwin.biology.utah.edu/pubshtml/PDF-Files/Bush24.pdf
Disease information has been collected via the Centers for Disease Control and Prevention (CDC) website: http://www.cdc.gov/