Zoonotic Diseases and Medical Hazards

What is a zoonotic disease?

Zoonotic diseases are diseases carried by animals, which can be transmitted to humans. For more information on zoonotic diseases carried by wildlife, please see the Index of Zoonoses.

How are zoonotic diseases spread?

There are several ways in which zoonotic diseases can be spread, some animals present higher risks of zoonosis because of increased shedding of harmful micro-organisms through their faeces, urine etc.

• Inhalation - Humans may inhale droplets containing harmful organisms originated from an infected animal. Dried faecal matter and dust in enclosures and cages may also contain harmful organisms; these can also be inhaled when they become airborne.
• Faecal-oral route - Animal faeces may pass directly from hands to mouth, or indirectly by way of objects, surfaces, water or food contaminated with faeces. The spread may occur after handling animals or coming into contact with their enclosures or cages.
• Skin or mucous membrane contact - Infections can be spread directly through animal bites and scratches, or indirectly when broken skin or mucous membrane comes in contact with contaminated animals and surfaces.
• Ingestion – consumption of contaminated food or water
• Urine - This occurs when urine is transferred from soiled hands or objects to the mouth.

Risk of contracting zoonotic diseases

Some people are more at risk of contracting a zoonotic disease than others and may also suffer more severe symptoms, these may include:

• Infants under the age of 1. This group is particularly at risk from both direct and indirect contact with animals, it is highly recommended that they do not have any contact whatsoever.
• Children under the age of 5. Closely supervise these children; never allow animals to lick their faces and hands.
• The elderly. This group is likely to have acquired immunity and therefor have a lesser risk of contracting disease; they may however suffer more severe symptoms to any disease in which they do not have immunity.
• Pregnant woman.
• Immuno-compromised children or adults. Includes people with diabetes, chronic kidney or liver disease, HIV and other severe illness, also those who are taking medications that impair their immune system.
• People with known allergies to some animals should be aware of the potential risk for an allergic reaction, and in the case of asthmatics, carry their relievers with them.

How to reduce the risk of spreading disease

Avoid activities with a higher risk. When rescuing or rehabilitating animals:

• Do not lick fingers or touch mouth or face with hands
• Do not consume food intended for animals
• Do not consume food when tending to animals
• Do not leave wounds uncovered
• Do not wipe hands on clothing or personal items
• Never allow children to touch anything from enclosures/cages until they have been thoroughly washed

Hand washing

Infectious diseases may be spread from either animals or their environment to people via contaminated hands, therefore hand washing is the most important practice in preventing both contraction and the spreading of disease. Correct hand-washing techniques and washing hands at the appropriate times will decrease the risk of disease.

Always wash hands with soap and running water after:

• Being licked or bitten by animals
• Contact with urine, faeces and soil in enclosures/cages
• Touching animals, their enclosures/cages, or food containers.

Proper hand-washing methods

• Using soap and running water, warm to hot is best
• Wetting hands thoroughly and lathering with soap
• Rubbing hands vigorously for at least 10-15 seconds (singing happy birthday slowly is a good measure of time)
• Pay attention to the back of hands, wrists, between fingers and under nails.
• Rinse hands well under running water
• Dry hands with disposable paper towel
• Use paper towel to turn off tap