This Environmental Health & Safety guideline documentation is intended for researchers and laboratory personnel.
Introduction
Several diseases can be transmitted between animals and people. These diseases are called zoonoses. Some zoonoses are of potential hazard in institutions conducting animal-research. While some zoonoses are very rare in laboratory rodents and rabbits raised for research purposes, they can be problematic for animal researchers or handlers who work with animals obtained from the wild or handled in the field. Certain zoonoses are very problematic for pregnant women or researchers or staff who are immunosuppressed. Awareness, proper and appropriate PPE use, certain vaccinations, avoidance and common sense will prevent most of these diseases.
Animal researchers and handlers should routinely maintain the cleanliness of their surroundings. Personnel handling animals should routinely wear non-latex gloves to protect against injury or self-inoculation, avoid mouth pipetting all solutions, use safety sharps, take time to give injections properly, avoid re-capping sharps, use a two-person team to give injections or do procedures on non-anesthetized animals, and use properly marked and stabilized sharps containers.
Animal researchers, animal handlers, animal facility staff should not handle animal wastes or bedding without appropriate PPE. Animal soiled PPE or clothes should not be taken home because researchers or staff can expose household members to allergens or biohazards. All laboratory personnel should not enter into research areas or vivaria unless they are authorized to do so and understand the potential health risks. All laboratory personnel should not handle research animals unless they are authorized by their Principal Investigators to do so.
Information regarding species-specific handling techniques may be obtained from the Institutional Veterinarian and veterinary staff. Rabies prevention and post-bite treatment protocols do not apply to bites from animals bred for laboratory use (e.g., rats, mice, hamsters, guinea pigs, rabbits, etc.) Rabies pre-and post-exposure prophylaxis procedures may be considered for researchers and staff who work with animals in the field or which have been caught from wild sources. However, all animal researchers and staff should be cautioned that both laboratory and non-laboratory animals have the potential to cause injuries and transmit zoonotic diseases.
Specific zoonoses and the animals associated with these illnesses are described in the panels below. Click on them for more information.
Bat Zoonoses
Histoplasmosis is a disease caused by the fungus Histoplasma capsulatum. The histoplasmosis fungus lives in soil, especially soil and material that is contaminated with and enriched by heavy accumulations of bat or bird droppings. Spores become airborne when contaminated soil is disturbed. Breathing the spores causes infection. The disease is not transmitted from an infected person to someone else. Infection with histoplasmosis is common, but the disease is rare. Most infected persons have no apparent ill effects and infection clears on its own without treatment. When people develop symptoms, it usually involves the lungs and is characterized by weakness, chills, fever, muscle aches, chest pains, and a dry cough. Chronic lung infections can resemble tuberculosis and may progress over months or years.
Prevention: Infection can be prevented by wearing protective, disposable coveralls, gloves and a dust mask. Before disturbing potentially-contaminated soil or debris, thoroughly mist-spray the material to control dispersion of dust and soil into the air.
Rabies is a preventable virus disease that causes an inflammation of the brain, and is almost always fatal once symptoms develop. Rabies is transmitted through the saliva of infected, warm-blooded animals. Worldwide, dogs are the most common source of rabies. In the United States, skunks, raccoons, foxes, coyotes, and bats are the main source of rabies infections. Most people who get rabies have been bitten by an infected animal, but getting the infected saliva from an infected animal into an open wound or mucous membrane of eyes, nose, or mouth can also lead to infection. Rabies is not spread by contact with bat feces, blood, or urine.
Rabies virus infects the central nervous system, causing brain inflammation and ultimately death. Early symptoms of rabies in humans are nonspecific, consisting of fever, headache, and general malaise. As the disease progresses, neurological symptoms appear and may include insomnia, anxiety, confusion, slight or partial paralysis, excitation, hallucinations, agitation, hypersalivation, difficulty swallowing, and hydrophobia (fear of water). Death usually occurs within days of the onset of symptoms.
Prevention: Rabies can be prevented by avoiding contact with infected animals, and providing pre-exposure and/or post-exposure vaccination to those who have high-risk contact with animals presumed to be infected, including bats.
Post-exposure treatment should begin as soon as possible after exposure. It begins with a dose of rabies immune globulin given partially in the wound, if possible, and partially in the deltoid shoulder muscle. This is followed by a series of 4 vaccination injections given over 14 days.
A pre-exposure vaccine regimen consisting of 3 inoculations over 28 days is strongly recommended for those working with laboratory or wild-caught bats. Completing the pre-exposure vaccine series does not eliminate the need for post-exposure treatment; it only reduces the need for the use of human rabies immune globulin.
In the event of a bat bite or mucous membrane exposure to bat saliva, it is critical that the following be done:
- Immediately wash the wound thoroughly with soap and water. Flush exposed mucous membranes of eye, nose, or mouth for 15 minutes at an eye wash station, sink drench hose, or hose from a potable water source.
- Proceed to the nearest emergency center for medical evaluation and appropriate post-exposure treatment.
Bird Zoonoses
Campylobacter
Campylobacter species can be found in pet and laboratory animal species. Transmission to humans is by the fecal-oral route and can produce an acute gastroenteritis. Symptoms include diarrhea, abdominal pain, fever, nausea, and vomiting.
Prevention: Use of personal protective clothing, good personal hygiene which include hand washing after contact with animals and their waste, and sanitation measures will help to prevent the transmission of the disease.
Influenza
Humans are the reservoir for the human-influenza virus but animal reservoirs are thought to contribute to the emergence of new human strains. Animal specific antigenic strains of influenza occur naturally in birds, swine, horses, mink and seals and may contribute to new human strains. Transmission is air-borne or by direct contact but the transmission of animal strains of influenza to humans is rare. Symptoms include fever, headache, sore throat, cough, and rhinitis. Pneumonia along with vomiting and diarrhea can also develop.
Prevention: Good hygiene and sanitation measures will help to prevent the transmission of the disease.
Newcastle Disease
Newcastle disease is caused by a paramyxovirus and can be seen in birds both wild and domestic. Transmi ssion is mainly by aerosol but contaminated food, water and equipment can also transmit the infection within bird colonies. Pathogenic strains produce anorexia and respiratory disease in adult birds. Young birds often show neurologic signs. In humans the disease is characterized by conjunctivitis, fever, and respiratory symptoms.
Prevention: The disease can be prevented by immunizing susceptible birds and obtaining birds from flocks free of infection. Good personal-hygiene practices which include hand washing after handling animals or their waste.
Psittacosis (Ornithosis, Chlamydiosis)
Psittacosis is caused by the bacteria Chlamydia psittaci. C. psittaci is common in wild birds and can occur in laboratory bird colonies. Infected birds are highly contagious to other birds and to humans. The organism is spread to humans by aerosolization of respiratory secretions or feces from the infected birds. Typical symptoms in the bird are diarrhea, ocular discharge, and nasal discharge. The infection in humans by C.psittaci, can cause fever, headache, myalgia chills, and upper and lower respiratory disease. Serious complications can occur and include pneumonia, hepatitis, myocarditis, thrombophlebitis and encephalitis. It is responsive to antibiotic therapy but relapses can occur in untreated infections.
Prevention: Only disease-free flocks should be allowed into the research facility. Wild-caught birds or birds of unknown status should be treated prophylactically for 45 days with chlortetracycline. Animal Biosafety Level 2 practices are recommended for personnel working with naturally infected birds or experimentally infected birds. Wearing NIOSH certified dust masks should be considered in rooms housing birds of unknown health status.
Salmonellosis
Along with a variety of other species, Salmonella, and other enteric bacteria are capable of causing disease in humans. Salmonellae are transmitted by the fecal-oral route. Infection produces an acute enterocolitis and fever with rare possible secondary complications such as septicemia.
Prevention: Use of personal protective clothing, good personal hygiene which include hand washing after contact with animals and their waste, and sanitation measures will help prevent the transmission of the disease.
Fish Zoonoses
Cryptosporidia
Cryptosporidium species have a worldwide distribution and can be found in many animal species including fish. Cryptosporidiosis is caused by protozoan parasites that live in the intestines of mammals. Cryptosporidiosis is transmitted by the fecal-oral route and can cause diarrhea in humans. Usually the diarrhea is self-limiting but in immunocompromised individuals the disease can have a prolonged course.
Prevention: Appropriate personal-hygiene practices which include washing hands after contact with animals or their waste should prevent spread of this organism.
Leptospirosis
Leptospirosis is widely distributed in domestic and wild animals. The possibility of transmission to humans from most animal species maintained in the laboratory should be considered but livestock and dogs would be the most common reservoirs. Fish and crustaceans are rarely, if ever, infected. Trapping of fish in the wild or growing fish in aquaculture settings is a risk for contracting Leptospirosis. Transmission of the organism to humans can occur through skin abrasions and mucous membranes by contact with urine or tissues of animals infected with Leptospirosis. Inhalation or ingestion of organisms can also transmit the diseases. Disease can vary from asymptomatic infection to severe disease ranging from flu-like symptoms to liver and kidney failure, encephalitis, and pulmonary involvement.
Prevention: Control of this infection in laboratory animal populations along with use of protective clothing and gloves by persons working with and caring for infected animals will help prevent disease.
Mycobacteriosis/Norcardiosis
Mycobacteriosis and nocardiosis are bacterial diseases of fish. In the fish external as well as internal lesions can be found resulting in anorexia, popeye, shin discolouration and external lesions such as ulcers, and fin rot. Transmission to humans is by bacteria entering abrasions. Persons infected with these bacteria may develop cysts or abscesses at the site of the abrasion that may ulcerate and scar.
Prevention: Wear protective gloves when cleaning fish aquaria or tanks as well as when handling or gutting fish.
Researchers and staff collecting fish from wild sources are at risk for other water-borne diseases, including Giardiasis and Cryptosporidiosis.
Rabbit & Other Lagomorph Zoonoses (Lab & Wild Caught)
Cryptosporidia
Cryptosporidium species have a world wide distribution and can be found in many animal species including guinea pigs. Cryptosporidiosis is caused by a protozoan parasite which lives in the intestine of mammals. Cryptosporidiosis is transmitted by the fecal-oral route and can cause diarrhea in humans. Usually the diarrhea is self-limiting but in immunocompromised individuals the disease can have a prolonged course.
Prevention: Appropriate personal-hygiene practices which include washing hands after contact with animals or their waste should prevent spread of this organism
Leptospirosis
Leptospirosis is widely distributed in domestic and wild animals. The possibility of transmission to humans from most animal species maintained in the laboratory should be considered but livestock and dogs would be the most common reservoirs. Transmission of the organism to humans can occur through skin abrasions and mucous membranes by contact with urine or tissues of animals infected with Leptospirosis. Inhalation or ingestion of organisms can also transmit the diseases. Disease can vary from asymptomatic infection to severe disease ranging from flu-like symptoms to liver and kidney failure, encephalitis, and pulmonary involvement.
Prevention: Control of this infection in laboratory animal populations along with use of protective clothing and gloves by persons working with and caring for infected animals will help prevent disease.
Pasteurella Multocida
Rabbits can transmit bacteria through bites and scratches. One of the common agents involved is Pasteurella multocida, a bacterium that resides in the oral cavity and upper respiratory tract of rabbits. Human infection is generally characterized by local inflammation with occasional abscess formation and ascending infection. Wounds can be readily treated with oral antibiotics.
Prevention: The use of protective clothing, disposable gloves, and hand washing along with good personal hygiene and proper animal handling techniques helps to reduce infection by Pasturella multocida.
Ringworm
Dermatophytes, which are fungi, cause ringworm in humans and animals. Infection in animals may be inapparent and is transmitted to humans by direct contact with infected animals or by indirect contact with contaminated equipment or materials. Dermatophytes produce flat, circular lesions that are clear in the center and crusted and red on the periphery.
Prevention: The use of protective clothing, disposable gloves, and hand washing along with good personal hygiene will help to reduce the spread of dermatophytosis in a laboratory animal facility.
Tularemia
Tularemia is a disease of rabbits and rodents caused by the bacteriumFrancisella tularensis. It is rarely found in laboratory-reared animals; more often found in wild-caught animals. The organism can be transmitted by a variety of ectoparasites, by contact with animal skin or environmental contamination, by inhalation of feces-contaminated dust, or by ingestion of insufficiently cooked infected animals. Human infections are usually the result of handling infected rabbits. In the U.S., wild rabbits are the source of infection in 90% of human cases. Symptoms of tularemia could include flu-like symptoms, diarrhea, progressive weakness, pneumonia-like symptoms, mouth ulcers, painful lymph swelling, and possibly painful swollen eyes.
Prevention: The use of DEET while working in the field, hand washing after handling animals along with good personal hygiene will help to reduce the risks for contracting tularemia from wild-caught animals.
Reptile & Amphibian Zoonoses
Cryptosporidia
Cryptosporidium species have a worldwide distribution and can be found in many animal species including cats. Cryptosporidiosis is caused by protozoan parasites that live in the intestines of mammals. Cryptosporidiosis is transmitted by the fecal-oral route and can cause diarrhea in humans. Usually the diarrhea is self-limiting but in immunocompromised individuals the disease can have a prolonged course.
Prevention: Appropriate personal-hygiene practices which include washing hands after contact with animals or their waste should prevent spread of this organism.
Salmonellosis
Along with a variety of other species, Salmonella, and other enteric bacteria are capable of causing disease in humans. Salmonellae are transmitted by the fecal-oral route. Infection produces an acute enterocolitis and fever with possible secondary complications such as septicemia.
Prevention: Use of protective clothing, personal hygiene which include hand washing after contact with animals or their waste, and sanitation measures prevent the transmission of the disease.
Laboratory-Reared Rodent, Hamster, Guinea Pig Zoonoses
Lymphocytic Choriomeningitis Virus
Lymphocytic choriomeningitis virus infects wild mice world-wide and laboratory animal species including mice, hamsters and guinea pigs. Humans can be infected by inhalation and by contact with tissues or fluids from infected animals. Symptoms include fever, myalgia, headache and malaise. More severe symptoms can occur such as lymphadeopathy, meningoencephalitis and neurologic signs.
Prevention: Serologic surveillance of animal colonies at risk and screening of all tumors and cell lines intended for animal passage will help to prevent LCM. Personnel should wear gloves when handling animals and practice appropriate personnel hygiene which includes hand washing.
Rat-Bite Fever
Rat-bite fever is caused by Streptobacillus monilformis or Spirillum mino., These organisms are in the respiratory tracts and mouths of rodents, especially rats. Most human infections are the result of a bite wound. Symptoms include chills, fever, malaise, headache and muscle pain. A rash can develop along with painful joints, abscesses, endocarditis, pneumonia, hepatitis pyelonephritis, and enteritis.
Prevention: Animals need to be handled properly to prevent bites.
Campylobacter
Campylobacter species can be found in pet and laboratory animal species. Transmission to humans is by the fecal-oral route and can produce an acute enteritis. Symptoms include diarrhea, abdominal pain, fever, nausea, and vomiting.
Prevention: Use of personal protective clothing, good personal hygiene, and sanitation measures will help to prevent the transmission of the disease.
Wild Rodent Zoonoses
Campylobacter
Campylobacter species can be found in pet and laboratory animal species. Transmission to humans is by the fecal-oral route and can produce an acute enteritis. Symptoms include diarrhea, abdominal pain, fever, nausea, and vomiting.
Prevention: Use of personal protective clothing, good personal hygiene, and sanitation measures will help to prevent the transmission of the disease.
Hantavirus Infection
Hantaviruses occur in rodent populations world-wide. Generally, wild-caught mice and sometimes other rodents have been implicated in outbreaks and infection of laboratory personnel has resulted from infected rats. The virus is shed in the respiratory secretions, saliva, urine, and feces of infected animals and is transmitted to humans by aerosol. Clinical signs in humans include fever, myalgia, headache, and cough followed by rapid respiratory failure.
Prevention: Hantavirus infections should be prevented through the detection of infection in incoming rodents and rodent tissues prior to their introduction into existing colonies. Animal biosafety level 4 guidelines are recommended for animal studies involving hantavirus infections in hosts such as Peromyscus maniculatus and wild caught rodents brought into the facility that are susceptible to hantaviruses.
Leptospirosis
Leptospirosis is widely distributed in domestic and wild animals. The possibility of transmission to humans from most animal species maintained in the laboratory should be considered. Transmission of the organism to humans can occur through skin abrasions and mucous membranes by contact with urine or tissues of animals infected with Leptospirosis. Inhalation or ingestion of organisms can also transmit the diseases. Disease can vary from asymptomatic infection to severe disease ranging from flu-like symptoms to liver and kidney failure, encephalitis, and pulmonary involvement.
Prevention: Control of this infection in laboratory animal populations along with use of protective clothing and gloves by persons working with and caring for infected animals will help prevent disease
Lymphocytic Choriomeningitis Virus
Lymphocytic choriomeningitis virus infects wild mice world-wide and laboratory animal species including mice, hamsters and guinea pigs. Humans can be infected by inhalation and by contact with tissues or fluids from infected animals. Symptoms include fever, myalgia, headache and malaise. More severe symptoms can occur such as lymphadeopathy, meningoencephalitis and neurologic signs.
Prevention: Serologic surveillance of animal colonies at risk and screening of all tumors and cell lines intended for animal passage will help to prevent LCM. Personnel should wear gloves when handling animals and practice appropriate personnel hygiene which includes hand washing.
Rat-Bite Fever
Rat-bite fever is caused by Streptobacillus monilformis or Spirillum mino., These organisms are in the respiratory tracts and mouths of rodents, especially rats. Most human infections are the result of a bite wound. Symptoms include chills, fever, malaise, headache and muscle pain. A rash can develop along with painful joints, abscesses, endocarditis, pneumonia, hepatitis pyelonephritis, and enteritis.
Prevention: Animals need to be handled properly to prevent bites.
Rodentolepsis
The tapeworm Rodentolepsis nana infects rats, mice and hamsters. Humans can be infected by ingestion of tapeworm eggs resulting in abdominal distress, enteritis, anorexia and headache.
Prevention: Preventing contact with the tapeworm ova present in feces and on fomites will help to control this zoonotic disease. Hand washing after contact with animals or their waste and wearing disposable gloves is appropriate. As cockroaches, beetles and fleas can act as intermediate hosts in the life cycle of this tapeworm in rodents, effective pest control should be in place.
Salmonellosis
Along with a variety of other species, Salmonella, and other enteric bacteria are capable of causing disease in humans. Salmonellae are transmitted by the fecal-oral route. Infection produces an acute enterocolitis and fever with possible secondary complications such as septicemia.
Prevention: Use of protective clothing, personal hygiene which include hand washing after contact with animals or their waste, and sanitation measures prevent the transmission of the disease.
Sheep, Cattle, Goat Zoonoses
Contagious Echthyma (Orf)
Orf is caused by a pox virus and is endemic in sheep and goat herds in the United States. Orf produces pustular lesions on the lips, nostrils, mucous membranes of the oral cavity in infected animals. Humans are infected by direct contact with exudates from the lesions or from fomites. The disease in humans is characterized by similar lesions on the hand, arm, or face or the person infected.
Prevention: Personnel who handle sheep, goats and cattle should wear protective clothing and gloves and practice good personal hygiene.
Cryptosporidia
Cryptosporidium species have a world wide distribution and can be found in many animal species including sheep, cattle, and goats. Cryptosporidiosis is caused by a protozoan parasite which lives in the intestine of mammals. Cryptosporidiosis is transmitted by the fecal-oral route and can cause diarrhea in humans. Usually the diarrhea is self-limiting but in immunocompromised individuals the disease can have a prolonged course.
Prevention: Appropriate personal-hygiene practices which include washing hands after contact with animals or their waste should prevent spread of this organism
Escherichia coli 0157:H7
The bacterial organism E. coli strain 0157:H7 can be found in the intestines of healthy cattle, sheep and goats. Meat can become contaminated during slaughter and milk can be contaminated from bacteria on the cow’s udder or on milking equipment. Other sources of infection include eating sprouts, lettuce, salami, unpasteurized milk and juice and swimming in or drinking sewage-contaminated water. Infected persons often have bloody diarrhea and abdominal cramps. In children under 5 years of age and the elderly, an E. coli 0157:H7 infection may cause hemolytic uremia and resulting kidney failure. Persons with diarrhea can transmit this organism to other people if personal hygiene is inadequate.
Prevention: Good personal hygiene to include frequent handwashing and observing no eating or smoking rules in animal areas will help to prevent this zoonotic disease.
Leptospirosis
Leptospirosis is widely distributed in domestic and wild animals. The possibility of transmission to humans from most animal species maintained in the laboratory should be considered but livestock and dogs would be the most common reservoirs. Transmission of the organism to humans can occur through skin abrasions and mucous membranes by contact with urine or tissues of animals infected with Leptospirosis. Inhalation or ingestion of organisms can also transmit the diseases. Disease can vary from asymptomatic infection to severe disease ranging from flu-like symptoms to liver and kidney failure, encephalitis, and pulmonary involvement.
Prevention: Control of this infection in laboratory animal populations along with use of protective clothing and gloves by persons working with and caring for infected animals will help prevent disease.
Psisttacosis (Ornithosis, Chlamydiosis)
Psittacosis is caused by the bacteria Chlamydia psittaci. C. psittaci is common in wild birds but can also cause enzootic abortion in sheep, goats, and cattle. Exposure to birth fluids and membranes of infected sheep and goats has been reported to cause gestational psittacosis in pregnant women. Symptoms of this zoonotic disease can include pneumonia, sepsis, and placental insufficiency resulting in premature birth or miscarriage.
Prevention: Pregnant animal workers should avoid contact with parturient sheep and goats.
Q Fever
Q fever is caused by, Coxiella burnetii which is a rickettsial organism. Infection is widespread in domestic animals and includes sheep, goats and cattle. Humans can be infected by inhalation of infectious particles. The organism is shed in urine, feces, milk, and birth products of domestic sheep, goats, and cattle. Symptoms in humans are usually flu-like. In some cases more serious symptoms can occur especially in elderly patients or in immuno-suppressed people. During pregnancy, Q fever infection has been associated with prematurity, low birth weights and placentitis with miscarriage possible. Thus, pregnant animal handlers should not expose themselves to animals or their birth products which could potentially carry the Q-fever organism.
Prevention: Serologic status of individual sheep is not an accurate indicator of whether an animal is shedding organisms but consistently negative serology on a herd basis does provide some assurance of Q fever – free status.
Rabies
The incidence of rabies in wildlife in the United States has increased in recent years and there is a possibility of skunk rabies to farm mammals, including horses and cows which are normally not vaccinated against rabies. Rabies is very rare in the laboratory environment but any random source animal, farm animal or wild animal showing central nervous system signs must be considered a potentially rabid animal. The rabies virus is most commonly transmitted to other animals or humans by the bite of a rabid animal or by introduction of saliva containing the virus into skin wounds or intact mucous membranes. Rabies produces a fatal acute viral encephalomyelitis.
Prevention: Pre-exposure immunization should be available to personnel working with or caring for animals of uncertain vaccination status or those who work with wildlife known to be reservoirs of rabies.
Ringworm
Dermatophytes, which are fungi, cause ringworm in humans and animals. Infection in animals may be inapparent and is transmitted to humans by direct contact with infected animals or by indirect contact with contaminated equipment or materials. Dermatophytes produce flat, circular lesions that are clear in the center and crusted and red on the periphery.
Prevention: The use of protective clothing, disposable gloves, and hand washing along with good personal hygiene will help to reduce the spread of dermatophytosis in a laboratory animal facility.
Salmonellosis
Along with a variety of other species, Salmonella, and other enteric bacteria are capable of causing disease in humans. Salmonellae are transmitted by the fecal-oral route. Infection produces an acute enterocolitis and fever with possible secondary complications such as septicemia.
Prevention: Use of protective clothing, personal hygiene which include hand washing after contact with animals or their waste, and sanitation measures prevent the transmission of the disease.