Leptospirosis

Leptospirosis is most common in Queensland and north-eastern NSW. 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 (eg, rats, mice and wildlife)
• certain work activities:
  • eg tasks that may cause skin injuries (scratches, thorn pricks, etc)
  • significant earthworks that could disturb and scatter animals (such as mice groups, forcing them to merge with other mice groups)
• insufficient protective measures.

Establish which animal species in your workplace and surrounding area can potentially carry leptospirosis then apply control measures:

• Vaccinate livestock and dogs (particularly if dogs are rodent-catchers and/or have regular access to areas where rodents are likely to live), where practicable. Vaccines are available for cattle, dogs and pigs that provide short-term protection. Discuss this approach with your vet.
• Conduct regular pest control (baiting / traps) and pest monitoring to reduce certain animal reservoir populations, eg rats, mice and feral pigs.
• Reconsider doing earthworks (or other environmental disturbance) after periods of heavy rain or flooding as it can disturb infected 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.
• Prevent flood and water run-off where practicable.

Isolation and engineering controls prevent exposure between infection source/s and workers. You should:

• Drain or fence off low-lying, swampy areas.
• Install suitable fencing / screening / netting to separate:
  • livestock from contact with potential contaminated bodies of water (eg valley dams, rivers, ponds etc) and surrounding areas
  • animals from pastures with water-logged areas, including after heavy rains or floods
  • livestock from contact with neighbouring livestock or wildlife that could potentially be infected
  • livestock from pigs, piggeries and piggery effluent
  • animal reservoirs from human habitations, stored food and other crops
  • infected animals from non-infected animals
  • workers from potentially contaminated mud / wet areas.
• Install barriers (eg splash guards) and covers for urine drainage channels in dairy sheds.
• Install 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.

You should:

• Identify rat and mice population group locations.
• Monitor animal breeding seasons – including rats and mice.
• Monitor weather forecasts for heavy rain, cyclones, flooding – and designated person/s responsible.
• Investigate and monitor known sources of infection to reduce the risk of further exposures.
• Promptly consult with a doctor if you or your staff have any health concerns.

You should also develop and implement suitable safe work systems in consultation with workers and / or their HSRs:

• Cover all broken skin (cuts, grazes, abrasions, blisters, rashes, etc) 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 (to kill the bacteria) and dry thoroughly with disposable towels – particularly after handling potentially infected material and before eating, drinking or smoking. Workers with facial hair should also wash their face.
• Do not scrub hands or skin too harshly as this may cause small tears in the skin.
• Take extra care when using high-pressure wash-down, ie wearing face shields and directing the spray away from people
• Do not put livestock straight into pasture when effluent has been sprayed (unless you are certain the effluent is from a ‘clean’ source) and, where possible, allow pastures to dry before grazing.
• Provide kitchen and dining areas that are separate to work areas.
• Provide showers for workers.
• Wash contaminated clothing immediately after any contact with potentially contaminated animals, animal carcasses, animal tissues (eg placentas, stillborn or aborted material, etc) or soils / vegetation. Anyone handling and washing these clothing items should be educated on the risks and wear appropriate personal protective equipment (PPE).
• 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)
  • 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 (eg animal feed) to reduce environmental contamination and rodent numbers
  • maintain fences / screens / barriers to ensure they remain effective
  • do not feed raw offal to dogs and other animals
  • do not use rodent-contaminated feed
  • ensure an appropriate number of first aiders are trained, know how to deal with exposure, and are rostered on all shifts
  • conduct regular workplace inspections to identify exposure hazards.

Establish suitable systems that:

• encourage hazard and incident reporting
• ensure potential exposures are diagnosed and treated early
• relocate at-risk workers (eg who have eczema, are pregnant or trying to become pregnant) to work away from high risk areas and activities
• accommodate workers with medically-ordered work restrictions so far as reasonably practicable
• display signage / information when exposure to leptospirosis is considered high-risk.

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 must cover:

• hazards that can cause leptospirosis
• risks of exposure
• controls and prevention strategies and how to use them, including good hygiene and decontamination practices
• how to recognise signs and symptoms of potential leptospirosis in themselves or their co-workers
• how to report potential exposure hazards and incidents
• the need to seek immediate medical treatment from a doctor skilled in leptospirosis diagnosis and treatment
• the type of PPE to be used, how to correctly wear it and maintain / dispose of it.

In high-risk workplaces:

• Animal handlers should treat all animals as if they are infected and wear full protection at all times.
• Agricultural and horticultural workers should treat all wet soil and vegetation as if it is infected and wear full protection, particularly after heavy rain, flooding or where significant earthworks were recently done in areas nearby your workplace.

Wearing or using different types of PPE does not eliminate or minimise the risk – it acts only as a barrier between the risk and the worker. In relation to 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 (eg dairy workers need different PPE to fruit pickers)
• the environmental conditions (indoors / outdoors)
• the worker’s general health status.

Workers at risk of exposure to leptospirosis must be provided with, and wear/use, correct PPE:

• suitable gloves for the work being done (eg: 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, eg task rotation, etc
• full-cover, waterproof boots or shoes that do not allow water to enter from the top

NOTE: Gloves or boots must be changed immediately if they split or leak (before water softens the skin and allows bacteria in).

• goggles or face shields that protect the eyes, nose and mouth may be necessary, for activities that pose a risk of contaminated 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, and
  • sun safe hats for outdoor workers
• for animal handlers (eg. 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 eg: overalls

Monitor the combination of 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 health and safety representatives 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 can only be 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 ensure ongoing prevention, control and monitoring is implemented to identify and 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.