Zoonotic infections

Zoonotic infections    

Download Prospect's guide on zoonotic infections.

Zoonoses are diseases that can be passed from animals to humans. They are transmitted by viruses, bacteria, parasites and fungi. Animals carrying zoonotic germs may be unaffected and appear healthy, but the effects of infections on people can range from mild to deadly.

According to the Health and Safety Executive, approximately 300,000 people in a variety of occupations are potentially exposed. People at risk include employees in animal-related occupations, forestry workers and engineers who may be exposed to ticks when walking through bracken. The law requires employers to implement and follow precautionary and preventative measures to control risks where possible.

Symptoms and conditions

About 40 potential zoonoses exist in the UK, each with its own particular channel for infection and mode of transmission. Symptoms caused by a zoonotic infection can range from the mild to severe, depending on the particular disease.

Some examples of zoonoses are:

  • Bovine tuberculosis – a bacterial disease of humans and animals, which presents similar symptoms to other forms of TB. In the UK it is most commonly found in cattle, deer and badgers
  • Avian influenza – a disease of birds caused by influenza A viruses. Human illness can range from conjunctivitis or mild flu-like symptoms to severe respiratory illness
  • Leptospirosis – a bacterial infection spread either via direct or indirect contact with rat urine (Weil’s Disease) or cattle urine (Hardjo). Some cases are asymptomatic or have mild flu-like symptoms. In more severe cases, symptoms include fever, severe headache, muscle pain and vomiting, and may lead to jaundice, meningitis and kidney failure.


Transmission can occur by a number of routes, from indirect contact through food or drink to direct contact through occupational exposure. The five most common routes to a zoonotic infection are:

  • direct contact with an infected animal’s saliva, blood, urine, faeces or other bodily fluids
  • indirect contact with objects that have been contaminated, such as feeding bowls, shovels and clothing
  • vector-borne transmission through mosquito, tick and flea bites or contact with flies
  • oral transmission, for example by eating contaminated food
  • aerosol transmission, where pathogenic agents are carried in aerosol droplets (this can also occur with dust)

The most common route to infection in occupational settings is by direct contact. But exposure can also occur through aerosol or vector borne transmission.

What your employer should do

Like other occupational health and safety risks, employers are required to protect the health, safety and wellbeing of their staff under the Health and Safety at Work Act 1974. But more specific regulations also apply in the workplace for preventing, controlling and reporting zoonotic infections.

Micro-organisms that present a risk to human health are classed as substances hazardous to health in the Control of Substances Hazardous to Health (COSHH) Regulations 2002. These require employers to carry out a COSHH assessment to:

  • identify work that may involve exposure to zoonotic pathogens
  • establish how they may cause harm
  • determine measures to put in place to prevent or reduce the risk of harm.

Find out more about controlling risks posed by hazardous substances.

Two main approaches are used to control infection in the workplace:

  • disciplined personal hygiene – this includes things like washing hands, wearing suitable protective clothing and safely disposing of contaminated waste
  • good environmental hygiene and design – this includes using equipment that is easy to clean and decontaminate, keeping equipment clean and ensuring, where possible, that the workplace is designed to be safe to use and easy to clean and decontaminate.

What you can do

  • wash your hands (and arms if necessary) before eating, drinking, smoking, using phones etc
  • cover cuts and grazes with waterproof dressings and/or gloves before starting work
  • if cuts and grazes occur while you are working, wash them immediately with soap and running water and apply a waterproof dressing
  • take rest breaks and meal breaks away from the main working area
  • wear appropriate protective clothing to stop personal contamination eg, waterproof/water-resistant protective clothing, plastic aprons, gloves, rubber boots/disposable overshoes
  • ensure protective clothing is safely disposed of or, if appropriate, cleaned thoroughly
  • dispose of all contaminated waste safely.

Find out more