Edition 17: Zoonotic diseases

• What are zoonotic diseases?
• Reducing exposure to zoonoses
• Personal health and hygiene
• Managing animal health
• I suspect a zoonotic disease – what do I do?
• Further information

Zoonotic diseases are infectious diseases that can pass between animals to humans or humans to animals.

Figure 1 https://www.cdc.gov/onehealth/basics/zoonotic-diseases.html

Zoonotic pathogens may be bacterial, viral, parasitic, or other agents that spread to humans through direct contact or through food, water, or the environment. Zoonotic diseases can range from minor short-term illnesses to major life-changing illnesses - some can even cause death.

People most at risk of being affected by a zoonotic disease are those in close contact with animals or animal products, including veterinarians, farmers, abattoir workers, shearers, , pet owners, and pig hunters. Children, elderly people, pregnant women, and people with impaired immunity are also generally at higher risk.

Understanding the risks and knowing how to manage zoonotic diseases is an important part of backyard biosecurity and should be included in your farm biosecurity plan.

Some examples of zoonotic diseases include:

Q Fever

Q fever is an infectious disease that produces flu-like symptoms in humans but shows little or no symptoms in animals.

Q fever is spread to humans from cattle, sheep, goats, and wild pigs.  People can become infected when splashed with infected body fluids or by breathing infected dust.

Q fever vaccination is highly recommended for people working in the livestock industry. Visit the Victorian Department of Health or the National Centre for Farmer Health for more information.

Hydatids

In the past, hydatids were a significant cause of illness in Australian rural communities due largely to the practice of feeding offal of sheep to farm dogs, the absence of treatment of tapeworm in farm dogs, and the close physical connection between farmers and their dogs.

Hydatids continue to remain a threat to human health and children are at particular risk due to their close contact with dogs.

When a person becomes infected, cysts may develop in the liver, lungs, or brain and the consequences may be fatal. The only treatment in humans is radical surgery to remove the cysts.

Hydatid disease can be prevented by:

• Worming dogs regularly with an all-wormer that is effective against tapeworm.
• Never feeding raw offal to dogs.
• Promptly disposing of dead stock
• Keeping dogs kennelled or chained when not working, to prevent them from finding offal or dead stock.
• Restricting access of dogs to household vegetable gardens and washing all vegetables thoroughly before consumption.
• Good hygiene, such as ALWAYS washing hands after handling dogs and before eating.

Salmonella

Salmonellosis (or Salmonella) is a disease caused by infection with Salmonella bacteria. Salmonella is usually spread to humans through eating undercooked food made from infected animals (for example undercooked meat, poultry, or eggs). It can also be spread from animals to humans in contaminated manure.

Poddy calves, although friendly, their habits of, licking clothes, sucking on fingers, and wanting to play, can present a significant risk, as carriers of zoonotic diseases including Salmonella and ringworm. 

Safe food handling and thorough handwashing can help prevent salmonellosis.

For more information visit the Victorian Government’s BetterHealth Channel.

Other zoonoses include (but are not limited to):

• Anthrax
• Avian influenza
• Australian bat lyssavirus
• Brucellosis
• Hendra virus disease
• Leptospirosis
• Psittacosis
• Ringworm
• Toxoplasmosis

There are several things you can do to reduce exposure to a zoonotic disease:

• Use personal protective equipment (PPE). The use of PPE is particularly important where contact with animal tissues, faeces or urine is likely, or the risk of infection is high. 
• Wear PPE like overalls, gloves, eye protection and masks and take care when assisting or being near animals when they are birthing or are sick.
• Regularly clean and disinfect workspaces and equipment, including PPE, instruments, harnesses, and rugs.
• Children and pregnant women should avoid areas where animals (especially cats) may defecate.
• Dog owners should appropriately dispose of their animals’ faeces, especially from public places.

There are simple things you can do to protect yourself and your family from zoonotic diseases:

• Wash hands with soap for 10-20 seconds under running water after handling animals and before preparing or eating food/drink.
• Use hand sanitisers, such as alcohol-based hand rubs, where there is no water.
• Promptly treat cuts or abrasions.
• Vaccinate for key zoonoses, for example Q fever.

To maintain good animal health, include the following management practices on farm and keep records in your farm biosecurity plan:

• Keep livestock healthy and vaccinate them for known zoonotic diseases where appropriate. Keep a record of vaccinations and identify any changes.
• Monitor stock health and seek early advice from a veterinarian or Agriculture Victoria animal health officer about unusual sickness or death.
• Regularly worm pets as appropriate.
• Control pest animals such as rats, feral pigs, wild dogs, and feral cats that may spread zoonotic diseases.
• Practice good hygiene with livestock feeds and prevent access from rodents and cats.
• Isolate and treat sick animals to reduce the risk of spreading disease to other animals and humans.
• Dispose of carcasses and afterbirth appropriately to prevent the spread or recurrence of diseases.

Report any unusual signs or suspected cases of an emergency animal disease immediately to the Emergency Animal Disease Hotline on 1800 675 888. Early reporting increases the chance of effective control and eradication.

Seek urgent medical attention for suspicious signs of zoonotic disease – if you live or work with livestock or wildlife inform your doctor so they can check for zoonotic diseases.

For human health advice, visit your GP, closest public health unit or the Victorian Government’s BetterHealth Channel – ensure you advise medical staff that you have been in contact with livestock or animals.

• Animal Health Australia – Zoonotic Diseases
• Australian Q Fever Register – About Q Fever
• Farm Biosecurity - Are you zoonosis aware?
• Safework Australia – How personal protective equipment helps to manage risks
• Victorian Government - BetterHealth Channel

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Regards

Agriculture Victoria