Diseases Transmittable to Humans
There are quite a number of diseases that can be transferred between wildlife and humans. Here is a list of diseases, including ones that may come to Australia from overseas due to movement of animals or humans:
Reptiles
Salmonellosis
Yersiniosis
Western Equine Encephalomyelitis
Sparganosis
Amphibians
Salmonellosis
Sparganosis
Tetraodontiae Poisoning
Birds
Salmonellosis
Yersiniosis
Tuberculosis
Colibacillosis
Erysipeloid
Staphylococcosis
Psittacosis
Blastomycosis
Cryptococcosis
Histomycosis
Eastern and Western Equine Encephalitis
St. Louis Encephalitis
Newcastle's Disease
Acariasis
Marsupials
Rabies
Trichinosis
Sparganosis
Anthrax
Dermatophytosis
Leptospirosis
Meliodosis
Mycobacterium bovis
Pasteurella multocida
Q fever
Salmonellosis
Scabies
Insects
Dermatophytosis
Bats
Rabies
Lyssavirus
Rodents
Salmonellosis
Yersiniosis
Plague
Tuberculosis
Leptospirosis
Lyme Disease
Relapsing Fever
Campylobacteriosis
Melioidosis
Tularemia
Rat Bite Fever
Pasteurellosis
Rocky Mountain Spotted Fever
Rickettsial Pox
Murine Typhus
Dermatophytosis
Venezuelan Equine Encephalitis
Hantaviruses
Lymphocytic Choriomeningitis
LaCrosse Encephalitis
Rabies
Acariasis
Ticks
Fleas
Babesiosis
American Trypanosomiasis
Giardiasis
Leishmaniasis
Capillariasis
Trichinosis
Angiostrongyliasis
Cestodiasis
Sparganosis
Schistosomiasis
Carnivores
Rabies
Trichinosis
Visceral Larval Migrans
Echinococcosis
Sparganosis
Many of these diseases can cause serious illness in humans and some are potentially fatal. Volunteer wildlife carers should seek medical advice on suitable strategies to prevent or minimise the chances of contracting a zoonotic disease from animals in their care. Contact your local government authority or Department of Health or your medical practitioner for further information.
Here are some details about some of the more serious disease conditions that occur in Australia:
a) Australian Bat Lyssavirus (ABL);
Australian bat lyssavirus (ABL) is a virus that can be transmitted from bats to humans, causing serious illness. The virus was first identified in 1996 and has been found in four kinds of flying foxes/fruit bats and one species of insect-eating microbat. Evidence of previous infection has been found in blood tests from a number of other bat species. It is therefore assumed that any bat in Australia could potentially carry the virus. The behaviour or appearance of a bat is not an accurate guide to whether it is carrying the virus.
Since November 1996, two people have died as a result of ABL infection after being bitten by bats. ABL is one of seven types of lyssavirus which are found around the world. Six of these are known to exist in bats but only ABL is known to occur in Australia. ABL is closely related but not identical to rabies, a serious and invariably fatal disease in humans.
b) Q fever;
Q fever is an infection with flu-like symptoms. It is transmitted from cattle, sheep and goats. It is a risk for people who work with these animals, such as abattoir workers and meat inspectors. Symptoms include fever, headaches, chills and muscle pains. A vaccine is available to protect people who are at risk.
c) leptospirosis;
Many different mammals can carry leptospira bacteria. In Australia, these are most commonly rats and mice, dogs, cattle, native animals, pigs (both domestic and feral), horses, cats, and sheep. Infected animals may have symptoms of the disease or may be completely well. Leptospira bacteria usually enter the body through skin cuts or abrasions, and occasionally through the lining of the mouth, nose, and eyes. Many different animals can harbour leptospira bacteria in their kidneys. Transmission can occur after contact with infected animal urine or flesh. Soil, mud, or water that has been contaminated with animal urine can be the source of infection.
d) ornithosis (Psittacosis);
Psittacosis is caused by the infectious agent Chlamydia psittaci and is an obligate intracellular bacterium.
Birds of all types act as a reservoir. This is especially common for psittacine birds (parrots, lorikeets, cockatiels, budgerigars) but also pigeons, turkeys, ducks and occasionally chickens. Healthy birds may be carriers. Cats, dogs, goats or sheep may be infected but this is rare.
The onset of psittacosis is usually abrupt with fever, prominent headache, photophobia, myalgia, and upper or lower respiratory tract symptoms. Dry cough is a common feature.
The illness usually lasts for seven to ten days and is mild or moderate. It may be severe in pregnant or older, untreated patients. Asymptomatic infection or mild flu-like illness may also occur.
Complications include encephalitis, endocarditis, myocarditis and thrombophlebitis. Relapses may occur, especially when there has been inadequate treatment.
Culture of the organism is generally not performed because of danger to laboratory workers.
Birds suspected of being infected should be referred to a veterinarian for diagnosis and treatment as required. The Avian Medicine Section at Primary Industries Research Victoria, Attwood (03) 9217 4200 has further details of specimen collection and transport requirements.
Most human cases are sporadic but outbreaks of infection may occur rarely within individual households or through contact with affected pet shops or poultry processing plants.
Infection is generally acquired by inhaling dust from dried faeces or fresh or dried ocular and nasal secretions from infected birds. Direct contact with birds is not required for infection. Rare person to person transmission has occurred.
Infected birds may shed the agent intermittently for a prolonged period. Shedding may be precipitated by stress on the birds such as cold, crowding or shipping. Dried secretions may remain infectious for many months.
Chlamydia psittaci is highly infectious. At risk groups include bird owners, pet shop employees, veterinarians, poultry-processing workers, zoo workers and taxidermists.
Wearing gloves and dust masks is recommended when cleaning areas with which birds have frequent contact such as cages and bird feeders.
For disinfection of floors and cages use a 1:100 dilution of household bleach in water or 70% isopropyl alcohol.
Outbreaks should be reported to your State Government department.
e) salmonellosis;
Human salmonellosis is one of the most common and economically important zoonotic diseases in the world (OIE, 2008). It is therefore important to recognise that macropods can harbour salmonellae without displaying clinical signs of disease (Samuel, 1982). It is not uncommon for people to come into
direct contact with macropods or their faeces in the urban environment, as kangaroos are commonly found grazing at local parks and golf courses and wildlife carers often hand-rear orphaned joeys.
Salmonellosis can affect anyone, however, it is more common in children under five years of age and young adults. The symptoms are often more severe in older people and people with other medical conditions.
The most common symptoms of salmonellosis are diarrhoea (which may contain blood or mucus), fever, stomach cramps, nausea, vomiting and headache.
Dehydration may occur, especially in infants and older people.
Illness usually lasts for a few days but Salmonella bacteria may be present in the faeces for several weeks or longer.
Salmonella bacteria are found in humans and in wild, farm and pet animals and birds, particularly chickens. They are also found in humans. As Salmonella infection of chickens is common, the bacteria can often be found in raw chicken meat and on eggs.
People with salmonellosis have Salmonella bacteria in their faeces. If they do not wash their hands properly after going to the toilet, then contaminated hands can spread the bacteria to surfaces and objects which may be touched by other people. Contaminated hands can also spread the bacteria to food which may be eaten by other people.
f) tuberculosis;
Tuberculosis is a sporadic cause of morbidity and mortality among fur seals and sea lions in Australia. In addition to its potential impact on the health of seal populations, tuberculosis originating in seals may have the potential to infect other mammalian species including humans and domestic livestock. It is important, therefore, to define the likelihood of transmission and disease-causing potential of seal tuberculosis to humans and livestock. This will enable public management strategies aimed at preventing pathogen transfer. In addition, knowledge of the epidemiology of seal tuberculosis will be of interest to livestock industries, particularly those involved in export of beef products.
Tuberculosis has never been reported in Australian brushtail possums (Trichosurus vulpecula). Given Australia’s strict quarantine system, and tight border controls, it is unlikely that M. bovis will be introduced by infected possums being brought into Australia from New Zealand.
g) yersiniosis;
Yersiniosis is a type of gastroenteritis caused by the bacterium Yersinia. Yersiniosis can affect anyone, however, it is more common in young children.
The most common symptoms of this disease are diarrhoea, fever, and vomiting.
Illness may last several weeks.
Yersinia bacteria are found in wild, farm and pet animals and birds, particularly chickens and pigs.
h) aspergillosis;
Aspergillus is a common fungus that can be found in indoor and outdoor environments. Most people breathe in Aspergillus spores everyday without being affected. Aspergillosis is a disease caused by this fungus and usually occurs in people with lung diseases or weakened immune systems. The spectrum of illness includes allergic reactions, lung infections, and infections in other organs.
Aspergillosis is a disease affecting the respiratory tract of birds and mammals. In regards to wildlife, aspergillosis is almost entirely confined to birds. It is caused by fungi in the genus Aspergillus, most commonly A. fumigatus. These fungi are ubiquitous in the environment and are especially common in soil and decaying plant matter. Birds are constantly exposed to the spores of Aspergillus. Under normal circumstances a bird's immune system will prevent infections from developing. If the immune system has been compromised, or if the bird has been exposed to an overwhelming number of spores, chronic or acute forms of the disease may develop.
The chronic form of the aspergillosis generally occurs in birds that have been weakened and stressed by malnutrition, injury, other disease, or exposure to toxicants. In the wild in New York, chronic aspergillosis is most often seen in gulls, common loons and raptors. It is a fairly common complication in wild birds that are held captive for rehabilitation.
i) scabies;
Sarcoptes scabiei is an obligate parasitic mite, 200-500 μm in length. Humans are the original host.
Scabies occurs throughout the world.
Scabies is widespread throughout Australia.
Australian native mammals affected: common wombat (Vombatus ursinus), southern hairy-nosed wombat (Lasiorhinus latifrons), koala (Phascolarctos cinereus), agile wallaby (Macropus agilis) and common ringtail possum (Pseudocheirus peregrinus). Introduced animals affected: red fox (Vulpes vulpes), dingo and dog (Canis familiaris), pig (Sus scrofa), horse (Equus caballus) and one-humped camel (Camelus dromedaries). Humans are also affected. Sarcoptic mange is endemic in common wombat populations throughout their range. The disease is relatively common in red fox populations.
The Sarcoptes scabiei mite is a tiny eight-legged creature barely visible to the naked eye. Females are 0.3 to 0.4mm long and 0.25 to 0.35 mm wide. Males are less than half the size of the female.
Scabies is a highly contagious parasitic skin infestation characterised by thin, slightly elevated, wavy grey-white burrows that contain the mites and eggs. Multiple papules and vesicles soon appear.
Immunosuppressed people, those living in institutions and the elderly may also show a clinical pattern of infestation similar to that in infants.
Scabies occurs worldwide regardless of age, sex, race, socio-economic status or standards of personal hygiene.
Humans are the primary reservoir. Other species of mite from animals or birds can also live on humans but do not reproduce in the skin.
Scabies is transmitted by:
· skin contact with an infected person
· contact with towels, bedclothes and under-garments if these have been contaminated by infested persons within the last four to five days.
The mites cannot jump or fly. Adult scabies mites may survive off the skin for up to 48 hours in room conditions.
j) ticks and lice
It is worth noting that lice are very host specific and thus animal lice do not attack humans (and vice versa). Ticks, however, are mostly not very host specific, and thus they may often attack humans, some species causing tick paralysis and many species transmitting viral, bacterial and protozoan diseases of animals to humans.
k) toxoplasmosis
Toxoplasmosis is caused by the protozoan parasite Toxoplasma gondii.
Cats, both domestic and feral cat species, are the definitive host. Australian marsupials can act as an intermediate host. Although toxoplasmosis is a significant cause of morbidity and mortality in wild marsupials
throughout Australia, its impact at a population level is not known.
The disease occurs world wide, wherever cats are found.
The disease occurs Australia wide.
While infection appears to be common in mammals and birds, relatively few individuals develop overt disease, with the exception of marsupials that seem to be much more sensitive. Infection is contracted through exposure to cat faeces, food or water that has been contaminated by cat faeces, or by eating the flesh of another animal that contains the parasite encysted in its muscles.
Clinical signs in marsupials are variable and include sudden death, blindness, keratitis, chorioretinitis, neurological signs, depression, anorexia, fever and dyspnoea. Toxoplasmosis should be high on the list of differential diagnoses for any marsupial that is displaying neurological signs, found dead, or showing vague symptoms with no obvious cause.
Diagnosis can by made in the live animal by submitting serum for testing.
Reptiles
Salmonellosis
Yersiniosis
Western Equine Encephalomyelitis
Sparganosis
Amphibians
Salmonellosis
Sparganosis
Tetraodontiae Poisoning
Birds
Salmonellosis
Yersiniosis
Tuberculosis
Colibacillosis
Erysipeloid
Staphylococcosis
Psittacosis
Blastomycosis
Cryptococcosis
Histomycosis
Eastern and Western Equine Encephalitis
St. Louis Encephalitis
Newcastle's Disease
Acariasis
Marsupials
Rabies
Trichinosis
Sparganosis
Anthrax
Dermatophytosis
Leptospirosis
Meliodosis
Mycobacterium bovis
Pasteurella multocida
Q fever
Salmonellosis
Scabies
Insects
Dermatophytosis
Bats
Rabies
Lyssavirus
Rodents
Salmonellosis
Yersiniosis
Plague
Tuberculosis
Leptospirosis
Lyme Disease
Relapsing Fever
Campylobacteriosis
Melioidosis
Tularemia
Rat Bite Fever
Pasteurellosis
Rocky Mountain Spotted Fever
Rickettsial Pox
Murine Typhus
Dermatophytosis
Venezuelan Equine Encephalitis
Hantaviruses
Lymphocytic Choriomeningitis
LaCrosse Encephalitis
Rabies
Acariasis
Ticks
Fleas
Babesiosis
American Trypanosomiasis
Giardiasis
Leishmaniasis
Capillariasis
Trichinosis
Angiostrongyliasis
Cestodiasis
Sparganosis
Schistosomiasis
Carnivores
Rabies
Trichinosis
Visceral Larval Migrans
Echinococcosis
Sparganosis
Many of these diseases can cause serious illness in humans and some are potentially fatal. Volunteer wildlife carers should seek medical advice on suitable strategies to prevent or minimise the chances of contracting a zoonotic disease from animals in their care. Contact your local government authority or Department of Health or your medical practitioner for further information.
Here are some details about some of the more serious disease conditions that occur in Australia:
a) Australian Bat Lyssavirus (ABL);
Australian bat lyssavirus (ABL) is a virus that can be transmitted from bats to humans, causing serious illness. The virus was first identified in 1996 and has been found in four kinds of flying foxes/fruit bats and one species of insect-eating microbat. Evidence of previous infection has been found in blood tests from a number of other bat species. It is therefore assumed that any bat in Australia could potentially carry the virus. The behaviour or appearance of a bat is not an accurate guide to whether it is carrying the virus.
Since November 1996, two people have died as a result of ABL infection after being bitten by bats. ABL is one of seven types of lyssavirus which are found around the world. Six of these are known to exist in bats but only ABL is known to occur in Australia. ABL is closely related but not identical to rabies, a serious and invariably fatal disease in humans.
b) Q fever;
Q fever is an infection with flu-like symptoms. It is transmitted from cattle, sheep and goats. It is a risk for people who work with these animals, such as abattoir workers and meat inspectors. Symptoms include fever, headaches, chills and muscle pains. A vaccine is available to protect people who are at risk.
c) leptospirosis;
Many different mammals can carry leptospira bacteria. In Australia, these are most commonly rats and mice, dogs, cattle, native animals, pigs (both domestic and feral), horses, cats, and sheep. Infected animals may have symptoms of the disease or may be completely well. Leptospira bacteria usually enter the body through skin cuts or abrasions, and occasionally through the lining of the mouth, nose, and eyes. Many different animals can harbour leptospira bacteria in their kidneys. Transmission can occur after contact with infected animal urine or flesh. Soil, mud, or water that has been contaminated with animal urine can be the source of infection.
d) ornithosis (Psittacosis);
Psittacosis is caused by the infectious agent Chlamydia psittaci and is an obligate intracellular bacterium.
Birds of all types act as a reservoir. This is especially common for psittacine birds (parrots, lorikeets, cockatiels, budgerigars) but also pigeons, turkeys, ducks and occasionally chickens. Healthy birds may be carriers. Cats, dogs, goats or sheep may be infected but this is rare.
The onset of psittacosis is usually abrupt with fever, prominent headache, photophobia, myalgia, and upper or lower respiratory tract symptoms. Dry cough is a common feature.
The illness usually lasts for seven to ten days and is mild or moderate. It may be severe in pregnant or older, untreated patients. Asymptomatic infection or mild flu-like illness may also occur.
Complications include encephalitis, endocarditis, myocarditis and thrombophlebitis. Relapses may occur, especially when there has been inadequate treatment.
Culture of the organism is generally not performed because of danger to laboratory workers.
Birds suspected of being infected should be referred to a veterinarian for diagnosis and treatment as required. The Avian Medicine Section at Primary Industries Research Victoria, Attwood (03) 9217 4200 has further details of specimen collection and transport requirements.
Most human cases are sporadic but outbreaks of infection may occur rarely within individual households or through contact with affected pet shops or poultry processing plants.
Infection is generally acquired by inhaling dust from dried faeces or fresh or dried ocular and nasal secretions from infected birds. Direct contact with birds is not required for infection. Rare person to person transmission has occurred.
Infected birds may shed the agent intermittently for a prolonged period. Shedding may be precipitated by stress on the birds such as cold, crowding or shipping. Dried secretions may remain infectious for many months.
Chlamydia psittaci is highly infectious. At risk groups include bird owners, pet shop employees, veterinarians, poultry-processing workers, zoo workers and taxidermists.
Wearing gloves and dust masks is recommended when cleaning areas with which birds have frequent contact such as cages and bird feeders.
For disinfection of floors and cages use a 1:100 dilution of household bleach in water or 70% isopropyl alcohol.
Outbreaks should be reported to your State Government department.
e) salmonellosis;
Human salmonellosis is one of the most common and economically important zoonotic diseases in the world (OIE, 2008). It is therefore important to recognise that macropods can harbour salmonellae without displaying clinical signs of disease (Samuel, 1982). It is not uncommon for people to come into
direct contact with macropods or their faeces in the urban environment, as kangaroos are commonly found grazing at local parks and golf courses and wildlife carers often hand-rear orphaned joeys.
Salmonellosis can affect anyone, however, it is more common in children under five years of age and young adults. The symptoms are often more severe in older people and people with other medical conditions.
The most common symptoms of salmonellosis are diarrhoea (which may contain blood or mucus), fever, stomach cramps, nausea, vomiting and headache.
Dehydration may occur, especially in infants and older people.
Illness usually lasts for a few days but Salmonella bacteria may be present in the faeces for several weeks or longer.
Salmonella bacteria are found in humans and in wild, farm and pet animals and birds, particularly chickens. They are also found in humans. As Salmonella infection of chickens is common, the bacteria can often be found in raw chicken meat and on eggs.
People with salmonellosis have Salmonella bacteria in their faeces. If they do not wash their hands properly after going to the toilet, then contaminated hands can spread the bacteria to surfaces and objects which may be touched by other people. Contaminated hands can also spread the bacteria to food which may be eaten by other people.
f) tuberculosis;
Tuberculosis is a sporadic cause of morbidity and mortality among fur seals and sea lions in Australia. In addition to its potential impact on the health of seal populations, tuberculosis originating in seals may have the potential to infect other mammalian species including humans and domestic livestock. It is important, therefore, to define the likelihood of transmission and disease-causing potential of seal tuberculosis to humans and livestock. This will enable public management strategies aimed at preventing pathogen transfer. In addition, knowledge of the epidemiology of seal tuberculosis will be of interest to livestock industries, particularly those involved in export of beef products.
Tuberculosis has never been reported in Australian brushtail possums (Trichosurus vulpecula). Given Australia’s strict quarantine system, and tight border controls, it is unlikely that M. bovis will be introduced by infected possums being brought into Australia from New Zealand.
g) yersiniosis;
Yersiniosis is a type of gastroenteritis caused by the bacterium Yersinia. Yersiniosis can affect anyone, however, it is more common in young children.
The most common symptoms of this disease are diarrhoea, fever, and vomiting.
Illness may last several weeks.
Yersinia bacteria are found in wild, farm and pet animals and birds, particularly chickens and pigs.
h) aspergillosis;
Aspergillus is a common fungus that can be found in indoor and outdoor environments. Most people breathe in Aspergillus spores everyday without being affected. Aspergillosis is a disease caused by this fungus and usually occurs in people with lung diseases or weakened immune systems. The spectrum of illness includes allergic reactions, lung infections, and infections in other organs.
Aspergillosis is a disease affecting the respiratory tract of birds and mammals. In regards to wildlife, aspergillosis is almost entirely confined to birds. It is caused by fungi in the genus Aspergillus, most commonly A. fumigatus. These fungi are ubiquitous in the environment and are especially common in soil and decaying plant matter. Birds are constantly exposed to the spores of Aspergillus. Under normal circumstances a bird's immune system will prevent infections from developing. If the immune system has been compromised, or if the bird has been exposed to an overwhelming number of spores, chronic or acute forms of the disease may develop.
The chronic form of the aspergillosis generally occurs in birds that have been weakened and stressed by malnutrition, injury, other disease, or exposure to toxicants. In the wild in New York, chronic aspergillosis is most often seen in gulls, common loons and raptors. It is a fairly common complication in wild birds that are held captive for rehabilitation.
i) scabies;
Sarcoptes scabiei is an obligate parasitic mite, 200-500 μm in length. Humans are the original host.
Scabies occurs throughout the world.
Scabies is widespread throughout Australia.
Australian native mammals affected: common wombat (Vombatus ursinus), southern hairy-nosed wombat (Lasiorhinus latifrons), koala (Phascolarctos cinereus), agile wallaby (Macropus agilis) and common ringtail possum (Pseudocheirus peregrinus). Introduced animals affected: red fox (Vulpes vulpes), dingo and dog (Canis familiaris), pig (Sus scrofa), horse (Equus caballus) and one-humped camel (Camelus dromedaries). Humans are also affected. Sarcoptic mange is endemic in common wombat populations throughout their range. The disease is relatively common in red fox populations.
The Sarcoptes scabiei mite is a tiny eight-legged creature barely visible to the naked eye. Females are 0.3 to 0.4mm long and 0.25 to 0.35 mm wide. Males are less than half the size of the female.
Scabies is a highly contagious parasitic skin infestation characterised by thin, slightly elevated, wavy grey-white burrows that contain the mites and eggs. Multiple papules and vesicles soon appear.
Immunosuppressed people, those living in institutions and the elderly may also show a clinical pattern of infestation similar to that in infants.
Scabies occurs worldwide regardless of age, sex, race, socio-economic status or standards of personal hygiene.
Humans are the primary reservoir. Other species of mite from animals or birds can also live on humans but do not reproduce in the skin.
Scabies is transmitted by:
· skin contact with an infected person
· contact with towels, bedclothes and under-garments if these have been contaminated by infested persons within the last four to five days.
The mites cannot jump or fly. Adult scabies mites may survive off the skin for up to 48 hours in room conditions.
j) ticks and lice
It is worth noting that lice are very host specific and thus animal lice do not attack humans (and vice versa). Ticks, however, are mostly not very host specific, and thus they may often attack humans, some species causing tick paralysis and many species transmitting viral, bacterial and protozoan diseases of animals to humans.
k) toxoplasmosis
Toxoplasmosis is caused by the protozoan parasite Toxoplasma gondii.
Cats, both domestic and feral cat species, are the definitive host. Australian marsupials can act as an intermediate host. Although toxoplasmosis is a significant cause of morbidity and mortality in wild marsupials
throughout Australia, its impact at a population level is not known.
The disease occurs world wide, wherever cats are found.
The disease occurs Australia wide.
While infection appears to be common in mammals and birds, relatively few individuals develop overt disease, with the exception of marsupials that seem to be much more sensitive. Infection is contracted through exposure to cat faeces, food or water that has been contaminated by cat faeces, or by eating the flesh of another animal that contains the parasite encysted in its muscles.
Clinical signs in marsupials are variable and include sudden death, blindness, keratitis, chorioretinitis, neurological signs, depression, anorexia, fever and dyspnoea. Toxoplasmosis should be high on the list of differential diagnoses for any marsupial that is displaying neurological signs, found dead, or showing vague symptoms with no obvious cause.
Diagnosis can by made in the live animal by submitting serum for testing.