Leptospirosis
Leptospirosis is considered a serious illness under Work Health and Safety laws in NSW. All cases acquired in the workplace must be reported to SafeWork NSW on 13 10 50.
Leptospirosis is an infectious zoonotic disease that is transmitted from animals to humans. The bacteria have been found in both domestic and wild animals including rodents, livestock, pigs, pets and wildlife.
There's no human vaccine for leptospirosis in Australia. The main source of infection occurs through work-related exposure.
How to manage leptospirosis risks in your workplace
Persons conducting a business or undertaking (PCBU), usually an employer or business, must take a risk management approach, in consultation with workers and/or their health and safety representatives to identify and eliminate and/or minimise the risk of exposure to leptospirosis in the workplace so far as is reasonably practicable.
Identify and control infection sources
Leptospirosis outbreaks usually follow periods of heavy rain. Outbreaks can be caused by a combination of factors including:
- Climatic conditions – heavy rain, flooding, rainfall runoff
- Local animal populations and breeding seasons (e.g. rats, mice and wildlife)
- Environmental changes such as significant earthworks that could disturb and scatter animals (such as rodents and mice groups)
- Certain work tasks and insufficient control measures
Identify environmental hazards and animal species in your workplace and surrounding area that could potentially carry leptospirosis then implement control measures to manage the risk of infection. This may include:
Environment
- Monitor weather forecasts for heavy rain, cyclones, flooding - prevent flood and water run-off where practicable.
- Identify rat and mice population group locations and monitor animal breeding seasons.
- Conduct regular pest control (baiting / traps) and pest monitoring to reduce certain animal reservoir populations (e.g. rats, mice and feral pigs).
- Clean-up rubbish and remove food sources around your workplace or onsite accommodation.
- Reconsider undertaking earthworks (or other environmental disturbance) after periods of heavy rain or flooding as it can disturb rat and mice population groups. In at-risk areas, an environmental health risk assessment should be considered when planning any work that involves significant environmental disturbance.
Animal Management
Good animal management can reduce the likelihood of infection or reinfection.
- Vaccinate livestock and dogs (particularly if dogs are rodent-catchers and/or have regular access to areas where rodents are likely to live). Vaccines are available for cattle, dogs and pigs that provide short-term protection. Discuss this approach with your vet.
- Install suitable fencing / screening / netting to separate:
- livestock from access to potentially contaminated bodies of water (e.g. valley dams, rivers, ponds) and surrounding areas.
- animals from pastures with water-logged areas, including after heavy rains or floods
- infected animals from non-infected animals
- livestock from contact with neighbouring livestock or wildlife that could potentially be infected
- animal reservoirs from human habitations, stored food and other crops
- Do not put livestock straight into pasture when effluent has been sprayed (unless you are certain the effluent is from a ‘clean’ source).
- Where possible, allow pastures to dry before grazing.
Isolation and engineering controls
Isolation and engineering controls prevent worker exposure to infection source/s. Some examples of isolation and engineering controls may include:
- Providing kitchen and dining areas that are separate to work areas.
- Draining or fencing off low-lying, swampy areas to prevent worker access to potentially contaminated mud / wet areas.
- Installing barriers (e.g. splash guards) and covers for urine drainage channels in dairy sheds.
- Installing properly built ponds or pits to contain effluent disposal.
Farming families should also have systems in place that segregate children and domestic animals from access to sheds, cattle yards and other potential infection sources.
Safe Systems of Work
Safe systems of work should be developed in consultation with workers and/or their health and safety representatives (HSRs) and implemented to manage the risk of exposure to leptospirosis including good hygiene practices, cleaning, training and information and personal protective equipment.
Hygiene
- Cover all broken skin such as cuts, grazes, abrasions, blisters and rashes with waterproof dressings or bandages before starting work. Ensure deeper wounds are fully healed before doing contact work like shearing or crutching.
- Regularly wash hands and arms with soap and dry thoroughly – particularly after handling potentially infected material and before eating, drinking or smoking. Do not scrub hands or skin too harshly as this may cause small tears in the skin.
- Shower after work and wash all cuts and scratches with clean water and soap.
- Wash clothing with laundry detergent in hot water if exposed to potentially contaminated animals, animal carcasses, animal tissues (including animal urine and droppings) or soil / vegetation. Anyone handling and washing clothing items should be aware of the risks and wear appropriate personal protective equipment.
Cleaning
- Practice good housekeeping.
- Regularly clean and tidy workplaces (including kitchen dining, toilets and hand-washing facilities) as well as domestic and recreational areas (where applicable).
- Take extra care when using high-pressure wash-down - i.e. wear face shields and direct the spray away from people.
- Control the build-up of vegetation and wood piles that may harbour rodents.
- Regularly remove rubbish (which can block drains in floods/heavy rain) and potential food sources for rodents (e.g. animal feed) to reduce environmental contamination and rodent numbers.
- Do not use rodent-contaminated feed.
Other workplace systems
- Conduct regular workplace inspections to identify sources of infection and exposure risks.
- Encourage hazard and incident reporting.
- Investigate and monitor known sources of infection to reduce the risk of exposure.
- Display signage / information when workplace exposure to leptospirosis is considered high-risk.
- Ensure an appropriate number of first aiders are trained in leptospirosis exposure and are available on all shifts.
- Ensure all possible infections are diagnosed and treated early.
- Reallocate at-risk workers (e.g. who have eczema, are pregnant or trying to become pregnant) to work away from high risk areas and activities.
Training and information
Training and information must be provided to all workers – including workers from culturally and linguistically diverse (CALD) backgrounds. Training should be competency-based, provided on commencement of employment and regularly reviewed.
Training and information should include:
- Hazards and infection sources
- Risks of exposure
- How to report hazards and incidents
- Controls and prevention strategies including good hygiene and cleaning practices
- The type of PPE to be used and how to correctly use, wear, store, maintain and dispose of it.
- How to recognise symptoms of leptospirosis in themselves and/or co-workers
- The need to seek immediate medical treatment from a doctor skilled in leptospirosis diagnosis and treatment
Use PPE
In high-risk workplaces:
- Animal handlers should treat all animals as if they are infected and wear full protection at all times.
- Farm, agricultural and horticultural workers should treat all wet soil and vegetation as if it is contaminated and wear full protection, particularly after heavy rain, flooding or where significant earthworks were recently done in areas nearby your workplace.
PPE does not eliminate or minimise the risk – it acts only as a barrier between the infection source and the worker. For leptospirosis, the aim of PPE is to prevent contaminated urine, water and fluids from getting through broken skin or the mucous membranes of the eyes, nose or mouth.
PPE type and effectiveness depends on:
- The work being done (e.g. dairy workers need different PPE to fruit pickers)
- The environmental conditions (indoors / outdoors)
- The worker’s general health status.
PCBUs must provide suitable PPE for workers at risk of exposure to leptospirosis and provide information, training and instruction on how to use, wear, storage, maintain and dispose of it. PPE may include:
- Gloves for the work being undertaken (e.g. full-fingered, puncture-resistant gloves for fruit pickers; mesh gloves for meat processing; nitrile/neoprene for milking cows; etc). Be mindful that prolonged use of some glove types may cause skin irritation and/or dermatitis for some workers – ensure these risks are appropriately managed, e.g. task rotation.
- Full-cover, waterproof boots or shoes that do not allow water to enter from the top. *Gloves or boots must be changed immediately if they split or leak (before water softens the skin and allows bacteria in).
- Goggles and/or face shields that protect the eyes, nose and mouth may be necessary for activities that pose a risk of splashes / airborne bacteria being ingested, inhaled or entering eyes.
- For agricultural and horticultural workers:
- long sleeve shirts when having contact with soil, vegetation or animal feed that is possibly contaminated
- sun safe hats for outdoor workers
- For animal handlers (e.g. milking, trimming, tagging, birthing, etc):
- disposable hats
- milking sleeves
- plastic aprons
- extra PPE may be needed when working in wet conditions or assisting with birthing e.g. overalls
Health monitoring
Monitor factors (animal, climate and environmental) that can initiate a leptospirosis outbreak.
Develop and implement systems to monitor the health of workers at risk of exposure to leptospirosis infection. Do this in consultation with workers and/or HSRs immediately before and during identified at-risk periods / conditions / situations.
Identify doctors in the local area who are skilled in leptospirosis diagnosis and treatment and ensure a contact list is available to workers.
Leptospirosis is diagnosed by two blood tests taken more than two weeks apart – confirmation of infection can take a further two weeks. In this period more workers could be exposed to the same source of leptospirosis infection.
If a worker is diagnosed with leptospirosis, the PCBU must have systems in place to prevent, manage and monitor exposure to prevent future cases or outbreaks. You should:
- Have a qualified occupational physician with experience in leptospirosis monitor workers and the workplace
- Conduct health monitoring for each worker involved in similar work activities
Provide workers who are diagnosed with leptospirosis with a report identifying their definitive test results and any recommendations regarding treatment and management of their disease.
Report leptospirosis cases
A ‘notifiable incident’ under the work health and safety legislation relates to:
- the death of a person
- a serious injury or illness of a person (eg being diagnosed with leptospirosis)
- a dangerous incident
arising out of the conduct of a business or undertaking at a workplace.
Leptospirosis is a prescribed serious illness under WHS legislation. If a worker is diagnosed with leptospirosis arising from work, you must notify SafeWork NSW by calling 13 10 50.
Cases of leptospirosis must also be notified to NSW Health – Public Health Unit.
About leptospirosis
Leptospirosis is most common in Queensland and north-eastern NSW. Outbreaks are more common in wet seasons following periods of heavy rain or cyclones and are usually associated with flood water contaminated with the urine from infected animals. Rainfall runoff and flood waters can also spread the bacteria to previously uninfected properties.
Exposure to leptospirosis
Leptospira bacteria colonise in an infected animal’s urine, birthing products and body tissues and when shed, contaminate their environment. Many infected animals do not display any signs of illness but can carry the bacteria for a long period of time.
The bacteria thrive in areas with warm, hot and humid climates with high rainfall and marshy/wet regions with alkaline soils which allow the bacteria to survive in the environment.
Human leptospiral infections may come from direct or indirect exposure to the bacteria:
- Direct contact with an infected animal’s urine, body tissues, birthing fluids or unpasteurised milk
- Indirect contact via contaminated water supply, moist/damp soil, mud or vegetation.
The bacteria from infected animals or environmental sources can enter the body in three ways:
- Absorption – through broken skin (cuts, abrasions, rashes, etc) via direct or indirect exposure
- Ingestion – via intact mucous membranes (nose, mouth, eyes) when eating / drinking, licking your lips or smoking using unwashed, contaminated hands
- Inhalation – via droplets of urine from infected cattle or rats and mice.
Eating contaminated food or drinking contaminated water has occasionally been responsible for transmission. Leptospirosis is not generally spread from person to person.
Workers at risk
Workers most at risk of exposure to leptospirosis are those who have close contact with animals or who are exposed to water, mud, soil or vegetation that has been contaminated with animal urine.
Some occupations are at higher risk of exposure such as:
- Farmers – particularly sugar cane and banana farmers.
- Agricultural and horticultural workers such as berry pickers
- Livestock and dairy workers (and any residents of the farming property)
- People who work with animals such as veterinarians and veterinary nurses, animal carers, zoo workers and wildlife carers
- Abattoir and meat processing workers; meat inspectors
- People who work with or are exposed to water sources, mud, soil or vegetation in high-risk areas such as plumbers, sewerage workers, drain layers, fishing industry workers, forestry workers, miners and emergency services personnel.
Some recreational activities that involve prolonged contact with contaminated water or soil such as camping, gardening, bushwalking, hunting and water sports can allow leptospirosis to be transmitted.
Symptoms and treatment
Symptoms of leptospirosis may vary – some people have no symptoms. Some may suffer flu-like symptoms such as fever and chills, headaches, muscle aches, cough, abdominal pain, nausea, vomiting, diarrhoea and red eyes. Some people go on to develop severe disease. Severe leptospirosis can sometimes be fatal.
Leptospirosis is commonly treated with antibiotics. Workers in high-risk occupations are advised to seek medical attention from a doctor skilled in leptospirosis diagnosis and treatment if they develop any of the above symptoms so symptoms can be properly investigated and diagnosed.