A. Bacterial Diseases

INFECTIOUS AGENT Brucella spp.

HOST White-tailed deer, fox, raccoons, and many other animals.

TRANSMISSION Contact with tissues, blood, urine, vaginal discharges, or fetuses of infected animals. Brucellosis is a highly contagious infection in many animals. It usually begins as a septicemia (blood infection) localizing in lymph nodes, spleen, reproductive organs, and joints where it can persist for long periods of time.

INFECTIOUS AGENT Yersinia pestis

HOST Fleas; often found on rats and ground squirrels

TRANSMISSION Flea bite. Wild rodents, rabbits, and mammals serve as the hosts to the fleas. The disease is endemic (indigenous) in the southwestern United States.

SYMPTOMS Wild rodents become infected but usually do not show clinical signs under normal conditions. The signs in animals are fever, pneumonia, and swollen lymph nodes. In humans, the disease is categorized into bubonic and pneumonic types. The bubonic form is characterized by a bacteremia and infected lymph nodes. Human mortality in untreated cases for this form of plague is 25-60%. The pneumonic form is characterized by an acute pneumonia and is rapidly fatal (1-3 days) if untreated (100%). Veterinarians have been killed by this disease.

INFECTIOUS AGENT Leptospira spp.

HOST Skunks, raccoons, opossums, Norway rats, mice, and many other animals including domestic species.

TRANSMISSION Bacterial penetration of abraded or lacerated skin by infected urine, contaminated food, water, or soil, or by direct contact with an infected animal. The organism can invade intact skin.

SYMPTOMS In wild animals, the disease is usually unapparent except in marine mammals. The disease is relatively rare in humans. A mild form is characterized by fever, chills, nausea, malaise, and myalgia (muscle pain). In the severe state, it may appear as a meningitis.

INFECTIOUS AGENT Chlamydia psittaci

HOST Birds (over 100 species including pigeons, raptors, and finches)

TRANSMISSION Fecal-oral contamination and inhalation of dried discharges and droppings from birds. The infecting organism is present in nasal discharges, droppings, and tissues of infected birds. The droppings are the most common route by which the disease is transmitted to humans. It is commonly found in feral pigeons that appear healthy.

SYMPTOMS Signs in animals include decreased or no appetite, resulting in emaciation, lethargy, respiratory signs, and a greenish blood-tinged diarrhea. Conjunctivitis is common and varies in severity. The disease may be acute and consequently the animal may die with few signs of disease. Clinical signs in people include fever, headache, upper respiratory infection, and pneumonitis. Rehabilitators, veterinarians, and bird banders have been infected by the birds they handled.

INFECTIOUS AGENT Salmonella spp.

HOST Birds and reptiles (most mammals also).

TRANSMISSION Fecal contamination of mucous membranes (fecal/oral). Food, water, or surfaces may become contaminated. Salmonella gastroenteritis is probably the most common zoonotic disease of humans. It is estimated there are two million cases annually in the United States. The organism is commonly found in animals, especially birds and reptiles.

SYMPTOMS Signs in animals are often subclinical, but when present, include diarrhea, vomiting, and mild fever. The bacteria are shed for some time following infection. Many animals are persistent carriers. In humans, the disease usually produces a gastroenteritis (intestinal infection) accompanied by diarrhea and often abdominal pain. Dehydration is often a problem.

INFECTIOUS AGENT Clostriduim tetanii

HOST No animal host.

TRANSMISSION Contamination through breaks in the skin from penetrating or crushing wounds.

SYMPTOMS Tetanus is an acute disease caused by the toxins produced in the body by Clostridium tetanii. The disease is characterized by tonic spasms of the muscle groups of the jaw, neck, and back. Untreated, there is a 70 percent mortality rate.

INFECTIOUS AGENT Francisella tularensis

HOST Rodents and lagomorphs (rabbits). Also included are over 100 species of mammals and 25 species of birds. It has been seen in fox, beaver, mice, and muskrats.

TRANSMISSION Handling infected animals, contamination of cuts, mosquito/fly/tick bites, and by inhalation. It can also be spread by touching the conjunctiva of the eye with dirty hands from handling affected animals.

SYMPTOMS In humans, signs are flu-like with an ulcer forming on the skin at the site the organism entered, this is followed by enlargement of the lymph nodes; if ingested, vomiting and diarrhea are seen; if inhaled, pneumonia. Severe systemic disease can lead to headaches, myalgia, chills, and fever. Humans do die from this disease.

PREVENTION Use rubber gloves when handling animals, especially rabbits; protection from ticks.

B. Mycotic Diseases

INFECTIOUS AGENT Aspirgillus fumigatus

HOST The fungus is ubiquitous (is found all over in our environment). Animal hosts in rehabilitation are generally wild birds such as raptors or waterfowl.

TRANSMISSION While under stress in a captive facility, rehab animals are more likely to develop the fungal disease. They in turn shed the spores of the fungus and the workers may inhale them.

SYMPTOMS In birds, respiratory signs. Most healthy people have no trouble resisting infection. However, this is not true for anyone who has been debilitated by illness, other diseases, or has been on long term antibiotic, antimetabolite, or corticosteroid therapy.

INFECTIOUS AGENT Histoplasma capsulatum

HOST Birds and bats

TRANSMISSION Inhalation of infective spores. Histoplasma capsulatum is widely distributed throughout the United States. The Mississippi and Ohio River valleys are areas of high concentration. The organism thrives in the soil that has been enriched by the presence of decaying bird or bat droppings. It is most likely to be found in roost areas that had been established for a minimum of three to five years. The organism grows in the upper 1-2 inches of the soil. When combined with moisture, roost areas are exceptional for the growth of Histoplasma.

SYMPTOMS The disease is acquired through inhalation of airborne spores. Upon first-time contact, the person will become infected. The majority of people who become infected develop only mild respiratory infections and, once recovered, become somewhat resistant. More severe infections are encountered in heavily-contaminated environments. The acute disseminated form, most frequent in children, may result in death. Similar forms of the disease occur in skunks, rats, opossums, foxes, and other animals.

PREVENTION Avoid accumulations of soil mixed with droppings from bats or birds. If occupation of such areas is necessary, use masks or a self-contained breathing apparatus. Always wear boots and properly bag clothing for washing. As a last resort, contaminated soil can be treated with a 3 percent solution of formalin to kill the spores, but such treatment will kill other organisms in the environment.

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