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Bird Mites Raccoon Roundworm Histoplasmosis
Bird Mites Bird mites in the genus Dermanyssus (Acarina: Dermanyssidae) are external parasites of birds, rodents and other mammals, which occasionally bite people when birds build their nests on homes. The most common member of this group is the Chicken Mite, which infests poultry roosts and wild bird nests. These mites are extremely small, but large enough to be seen by the naked eye. A recent sample of these mites submitted to lab also included several specimens of a predator mite in the genus Cheyletus, probably C. eduditus, which is commonly found in barns and dairies in association with acarid grain mites. C. eduditus is a bit smaller than the chicken mite and armed with a pair of heavy duty palps, each equipped with a long talon. The chicken mite feeds primarily at night when the birds return to the nest or roost area. They hide during the day in nearby cracks, crevices and other protected sites. These mites are known infest homes and bite people when bird nests are built on homes. Repeated bites can result in a rash and intense itching. Female mites can live a month or so without a blood meal and they can persist in the home after the source has been removed. Control of these parasites in homes begins with locating and removing the source of the infestation. If the residence has a history of rodent problems, measures must be taken to reduce the rodent population. Another source may be pet rodents like gerbels or hamsters. Once the nest or source is removed the surrounding area should be treated with a residual insecticide like Diazinon. The inside of the home can be treated with synergized pyrethrins (like household Raid) if the mites are found throughout the house. Be sure to read and follow all the instructions and safety precautions found on the pesticide label before using any pesticide
Raccoon Roundworm The raccoon roundworm (Baylisascaris procyonis) is the common large roundworm or ascarid found in the small intestinal tract of raccoons. Adult worms measure 15 to 20 cm in length and 1 cm in width. They are tan-white in color, cylindrical and taper at both ends. Distribution B. procyonis has been reported from numerous states, but probably occurs wherever the raccoon inhabits. Prevalence of infections ranges from 3.4% to nearly 100% of all raccoons sampled. In Michigan, the parasite has commonly been seen in raccoons statewide. There are several abnormal hosts that have been diagnosed as having a Baylisascaris infection: mice, squirrels, rabbits, birds, woodchucks, and chipmunks. Transmission and Development Transmission of B. procyonis can occur either directly or via an abnormal host. In the direct life cycle, eggs of Baylisascaris from an infected raccoon are shed in the feces and, within 30 days, a larval stage will develop within the egg (embryonated). Raccoons, especially young ones, become infected directly by accidental ingestion of the eggs. This may occur via the mother’s egg-contaminated body or from the local environment of the den (soil or vegetation). When an abnormal host is involved, embryonated eggs are ingested, the eggs hatch, and the larvae penetrate the intestines and migrate through the liver and lungs. They then continue on random migrations that can lead them to the head, neck and/or chest. The larvae finally become encysted in small fibrous nodules in the muscle, liver or lungs. If the abnormal host is eaten by a raccoon, the encysted larvae are released and migrate to the small intestine where they develop to the adult stage. Clinical and Pathological Signs In raccoons usually there are no clinical or pathological signs observed. In heavy infections, intestinal obstructions or a rupture of the intestinal tract may occur, due to the large number of parasites present. The animals usually seen with clinical and pathological signs caused by Baylisascaris are the abnormal hosts (mice, woodchucks, squirrels, rabbits, and birds). Migration of large numbers of larvae may cause liver and lung damage. Usually changes in behavior are seen due to central nervous system disorders. This is the result of damage caused to the brain and spinal cord by the larvae. Larvae may also cause eye disorders by migrating through the ocular tissues. If small numbers of larvae are involved in the migration, there may be no clinical signs observed. Fatal or severe central nervous system disorders have been documented for mice, gray and fox squirrels, ground squirrels, woodchucks, nutria, beavers, domestic quail, partridges, pigeons, exotic turkeys, emus, captive cockatiels, captive prairie dogs, foxes, armadillos and porcupines. In abnormal hosts unusual behavior is generally observed. The affected animal will initially exhibit a head tilt and an inability to walk and/or climb properly. As the clinical illness progresses the animal may lose its fear of humans, circle, roll on the ground, fall over, lay on its side and paddle its feet, become totally recumbent, comatose, and finally die. In humans, pathological lesions observed consist of skin irritations (cutaneous larval migrans) and eye and brain tissue damage (visceral larval migrans) due to the random migration of the larvae. The affected individuals may experience nausea, a lethargic feeling, incoordination and loss of eyesight. Diagnosis In raccoons, infection with Baylisascaris can be confirmed by recovering and identifying the adult worms (postmortem examination) or by fecal flotation (live animal) to identify characteristic ascarid eggs in the feces. Occasionally sub-adult worms are passed in the feces or vomitus. In abnormal hosts, the disease can be diagnosed after a postmortem examination. Larvae and associated lesions in the brain, eyes, and other tissues can be observed on microscopic examination. A Baylisascaris infection is often suspected by the history and clinical signs observed. In humans, based on the size of the larvae in the skin or eye lesions, cases of Baylisascaris infection can be determined. In the event of the death of the human, larvae can be detected in microscopic sections of the brain, heart, lungs, eyes and other affected tissues. Treatment and Control Raccoons can be successfully treated with several anthelmintics to kill the adult worms. Effective drugs are piperazine, fenbendazole, pyrantel pamoate, levamisole and organophosphates such as dichlorvos. There are currently no drugs that can effectively kill the migrating larvae in the body. Laser surgery has been successfully performed to kill larvae present in the retina of the eye but the damage caused by the migrating larvae is irreversible. Treatment with steroids in intermediate hosts is mainly supportive and is designed to decrease the inflammatory reaction. Controlling infections of this parasite requires minimizing contact with areas inhabited by raccoons. Fecal contamination of an area can result in millions of eggs being deposited and therefore available for infection. These eggs are extremely resistant to environmental conditions, being able to survive for several years. Any area contaminated with raccoon feces should be cleaned and the feces, as well as any contaminated feed, straw or hay, burned. Children and pets should be kept away from these contaminated areas until a thorough cleaning has occurred. Significance B. procyonis is of public health significance because it can infect humans, causing skin irritations and eye and brain damage due to the random migration of the larvae. There have been 2 human fatalities, but both occurred in young children and were the result of a child being exposed to open fireplaces in the home that had been contaminated by a pet raccoon and a child chewing on contaminated firewood brought into the home, respectively. There are other ascarids (Toxocara canis and Toxocara cati, the dog and cat roundworm, respectively) that can cause similar skin, ocular and nervous system problems. Transmission of these parasites is more likely than with Baylisascaris due to close human-pet association but the dog and cat roundworms are less pathogenic. Histoplasmosis What is histoplasmosis? Histoplasmosis is an infection that varies in symptoms and seriousness. It usually affects the lungs. When it affects other parts of the body, it is called disseminated histoplasmosis.
What is the infectious agent that causes histoplasmosis? Histoplasmosis is caused by Histoplasma capsulatum, a fungus. The fungus produces spores that can be inhaled when they get into the air. Spores are hardy forms of the fungus that can live in the environment for a long time.
Where is histoplasmosis found? The histoplasmosis fungus is found throughout the world. The fungus grows naturally in soil in some areas of the United States, mostly in the midwestern and southeastern states and along the Ohio and Mississippi River valleys. It thrives in soil that is enriched with bat or bird droppings.
How do people get histoplasmosis? Histoplasmosis is spread through the air. If soil containing the histoplasmosis fungus is disturbed, the fungus spores get into the air. People can breathe in the spores and get histoplasmosis. The disease is not spread from person to person.
What are the signs and symptoms of histoplasmosis? Most infected persons have no symptoms. When symptoms occur, they vary widely, depending on the form of the disease. The lung infection can be short-term (acute) and relatively mild, or it can be long-term (chronic) and serious. Symptoms of the acute lung infection are tiredness, fever, chills, chest pains, and a dry cough. The chronic lung infection is like tuberculosis and occurs mostly in persons who already have lung disease. It can progress over months or years and can scar the lungs. Disseminated histoplasmosis results in a variety of serious symptoms and can involve all body organs. The liver and spleen usually become enlarged, and sores in the mouth or gastrointestinal tract can develop. Disseminated histoplasmosis can be fatal.
How soon after exposure do symptoms appear? Symptoms of acute disease usually appear in 5 to 18 days (usually 10 days) after exposure.
How is histoplasmosis diagnosed? Diagnosis can be made by laboratory culture or a blood test. A skin test is available but is useful only for outbreak investigations, not for diagnosis.
Who is at risk for histoplasmosis? Anyone can get histoplasmosis. Chronic lung infections are more common in males than in females, and particularly in persons with chronic lung disease. Disseminated histoplasmosis occurs most often in infants, young children, and persons with weakened immune systems, such as those with cancer or HIV infection.
What complications can result from histoplasmosis? Acute histoplasmosis can keep getting worse or can become chronic. Acute histoplasmosis can also spread from the lungs to other organs and lead to the disseminated form of the disease, especially in persons with weakened immune systems.
What is the treatment for histoplasmosis? Persons with mild disease usually get better on their own. Severe cases of acute histoplasmosis and all cases of chronic and disseminated disease are treated with fungus-killing medicines.
How common is histoplasmosis? Infection with histoplasmosis is common, but the disease is rare. As many as 80 percent of persons living in U.S. areas where the fungus is common have a positive skin test, meaning they have had the infection in the past. However, most of these people do not have a history of histoplasmosis symptoms.
Is histoplasmosis an emerging infectious disease? Yes. Histoplasmosis is on the rise, mainly because of the growing number of persons with weakened immune systems. These include persons with HIV infection, those who have had a bone marrow or organ transplant, and those receiving chemotherapy for cancer.
How can histoplasmosis be prevented?
This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health-care provider. If you have any questions about the disease described above or think that you might have a fungus infection, consult a health-care provider. All Paws Wildlife Removal does not necessarily endorse products or services which may be advertised on this website by Google |
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