Wildlife Diseases and Wildlife Carers

 

Nigel Brown, District Veterinarian, Northern Tablelands Local Land Services, Glen Innes.

Introduction

Wildlife (animals and birds, insects and reptiles) can be affected by many diseases that can also infect people. Without showing any signs, they can also carry some infections that are a severe threat to people who handle them. Wildlife Carers are at extra risk because of the frequency with which they handle sick and injured animals. The dangers can be minimised by understanding the risks, effective hygiene procedures and, in some cases, vaccination against specific diseases.

Why are rescued wildlife such a risk?

Naturally, wildlife tries to stay distant from people but rescued animals are unable to escape. After rescue, they are passed along to carers. All animals, including wildlife, carry a normal burden of infectious organisms.

Healthy animals have developed a natural immunity which keeps those pathogens in small numbers but some wild animals naturally become infected with a new disease, fall sick and may be rescued. Similarly, the stresses of injury, becoming an orphan or starvation reduce an animal’s resistance to disease organisms allowing them to multiply in number so that animals can become sick themselves or discharge large amounts of infection to spread to other susceptible animals.

All rescued animals are therefore a serious disease risk to handlers. A disease which can affect both animals and people is called a ‘zoonosis’ (plural = zoonoses).

What are the most important zoonoses to think about?

The most common zoonotic diseases are shown in Table 1. Always seek medical advice for prevention and treatment. Do not attempt to treat yourself – these diseases can be dangerous or fatal in some people.

How can I reduce the risk of infection?

The most common routes of infection are by mouth, breathing in aerosols and through wounds while the most dangerous materials are body fluids. Faeces and urine are therefore probably the most likely source of infection – but it depends on the diseases involved. Respiratory diseases, for instance, will largely be spread by inhaling infected air. Always use good hygiene practices.

Discuss vaccinations against tetanus, Q fever and Australian bat lyssavirus with your doctor

Avoid mouth contact with wildlife.

Wash your hands frequently (preferably using water with soap or chlorhexidine disinfectants rather than chemical hand-sterilisers)

  • after handling animals and waste
  • before eating or drinking (and smoking!)
  • wear gloves when handling dead animals, as well as washing adfterwards

Seek urgent veterinary assistance for animals showing signs of respiratory or nervous diseases. Wear a face mask and avoid working with such animals in confined spaces to reduce the chances of inhaling infection.

Only handle bats after receiving full vaccinations.

Use appropriate protective equipment, especially when handling unknown animals.

And, most importantly, do no put your family at risk, especially if they have weakened immunity by being young, old or sick themselves.

Table 1 Some Zoonoses found in Wildlife

Wildlife

Major Infections

Notes about Disease in People

All mammals, reptiles and birds Salmonella / Campylobacter / Giardia / Cryptosporidium Diarrhoea
Tetanus Environment is contaminated by spores which enter through wounds, scratches or bites. Vaccination is available.
All mammals Ringworm Several types of skin disease, can take some time for disease to develop.
All marsupials Toxoplasma gondii Abortion in people, birth defects. Spread by cats and rodents especially in cat faeces.
Bats Hendra virus Brain disease. No vaccine – fatal disease.
Australian Bat Lyssavirus Preventive vaccine recommended.
Macropods Ross River virus Spread by mosquito bites. Rash, joint-pains, headache and fever,
Coxiella burnetii (Q fever) Flu-like. Spread by inhalation of dust.

Vaccine available.

Echinococcus granulosus

(= hydatid tapeworm)

Abdominal pain, cysts develop in various organs. Also found in environment from dog and dingo faeces.
Wombats and Koalas Sarcoptes scabei Skin disease – rash and itchiness.
Bandicoots Coxiella burnetii (Q fever) Flu-like. Spread by inhalation of dust.

Vaccine available.

Rodents, Possums and Platypus Leptospira Flu-like. Spread in urine.
Birds Chlamydia (Psittacosis) Flu-like disease.
Murray Valley encephalitis virus Spread from birds by mosquito bites – fever, headaches and vomiting.
Avian influenza virus (bird-flu) Flu-like disease.
Mycobacterium avium Pneumonia.
Reptiles Mycobacteria Skin ulcer or respiratory disease.
Salmonella Intestinal problems.

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