Q fever is an infectious disease caused by a type of bacteria (Coxiella burnetii) that infects some livestock, companion animals and wildlife. It's a zoonosis, which means that infected animals can spread infection to people.
Infected animals shed bacteria in their urine, faeces and milk, and in especially high numbers in birth products. This can cause widespread contamination of the animal's environment. The bacteria tolerate harsh conditions (including drought) and may persist in the environment for months to years.
Q fever and people
The bacteria can get into your lungs through normal breathing if the bacteria are airborne in dust or aerosols (e.g. aerosols are created when you use high-pressure sprays to clean equipment). Infection can also occur from close (physical) contact with infected animals.
Many people who are infected with Q fever do not become sick or they have a mild illness that is sometimes mistaken for a cold. People who become acutely ill with Q fever usually develop an influenza (flu)-like illness which can sometimes require admission to hospital.
Most people make a full recovery from Q fever. However, some people with Q fever infection develop chronic fatigue or other health problems. Early treatment with appropriate antibiotics can reduce the time people are unwell with Q fever. Further information on Q fever and human health can be found on the Queensland Health website.
Are construction workers at risk of Q fever?
While Q fever most commonly infects people who work with animals and associated products and waste, there is a risk to people doing construction work if the site has previously been used for livestock grazing or is heavily contaminated with kangaroo excreta (urine and faeces). The risk varies depending on:
- how long ago the land was used for livestock grazing
- the extent to which the site is contaminated with excreta from livestock, kangaroos and wallabies
- the extent of soil disturbance and dust
- the prevailing weather conditions, especially dry and windy conditions.
Managing Q fever risks at construction workplaces
Airborne dust from earthworks, excavation and digging activities can potentially expose people to the risk of Q fever if the site has recently been used for livestock grazing or is densely populated with kangaroos. You should identify construction activities that are likely to generate dust and plan how to prevent or suppress the dust. This should be prepared well in advance of works starting on the site and communicated to the people who will be required to apply them.
Environmental sampling to test for the presence of Q fever bacteria in soil is not recommended as this does not provide a reliable indicator of risk.
Ways to manage dust include:
- Use engineering and design controls to manage dust (e.g. dust screens, dust catchers fitted to equipment, mechanical ventilation systems, wind breaks and barriers).
- Use water to suppress dust and prevent it from becoming airborne (e.g. use water tankers, static sprinklers and other watering methods).
- Protect the soil from wind erosion (e.g. by applying protective ground cover such as mulch and vegetation, using chemical bonding agents or treatments, and covering or sealing transitory mounds of soil).
- Revegetate or seal exposed soil once earthworks are completed.
- Equip earthmoving machinery with an enclosed and ventilated cabin.
- Fitting high efficiency air filtering systems (e.g. HEPA filters) to the intake and cabin recirculation air intake of front end loaders, excavators and other machinery.
- Locate car parks, site entry, offices, washing facilities and dining facilities away from areas where dust is generated and keep doors and windows closed to keep the dust out.
- Avoid using high pressure water systems to clean dirt and dust from surfaces and equipment.
- Provide vehicle washing facilities and where necessary wash down vehicles before leaving the site.
- Minimise site disturbance (e.g. by keeping vehicle movements to a minimum, limiting traffic movement over loose soil, keeping general site traffic to watered, treated or sealed haul roads and limiting vehicle speed).
- Wash hands regularly and clean dust and soil off work boots before entering site buildings.
- Use a properly fitted (PDF, 0.86 MB) particulate respirator to protect against dust and instruct workers in its correct use and fit.
- Ensure regular cleaning of areas to minimise the accumulation of dust and dirt.
- Clean surfaces and equipment using wet cleaning rather than dry sweeping or using compressed air.
Inform workers about the possible risk of Q fever and to tell their doctor about their work if they become sick with a flu-like illness. The doctor can test for Q fever if indicated and treat the person with antibiotics if they are found to be infected.
If workers have unavoidable exposure to potentially infectious dust, seek medical advice about Q fever screening and vaccination. Screening consists of a skin and blood test and a detailed medical history. Workers with a positive skin or blood test do not require vaccination. Immunity generally develops 15 days after vaccination and is long lasting.
The Q Fever Register has a list of doctors who provide Q fever screening and vaccination.
Workers who have completed Q fever screening and vaccination are able to store this information on the Q Fever Register.
Is there an ongoing Q fever risk on completion of construction work?
There may be an ongoing risk of Q fever at workplaces such as solar and wind farms once construction work is completed and the site becomes operational, especially if livestock are kept at the site or it is densely populated with kangaroos and wallabies.
People who have contact with livestock or who mow and slash grass contaminated with animal excreta are most at risk. Apply controls to this work and seek medical advice about Q fever screening and vaccination for these workers.
You must notify Workplace Health and Safety Queensland if a worker has acquired Q fever at work.
Contact the Workplace Health and Safety on 1300 362 128 for information on managing Q fever at work.
Contact Queensland Health on 13HEALTH (13 43 25 84) for information on Q fever and human health. Seek advice from your general practitioner or local public health unit if you have concerns about possible exposure to Q fever.
Contact the Q Fever Register on 1300 QFEVER (1300 733 837) or visit www.qfever.org for information on Q fever vaccine providers and to register immune workers.