Q Fever, or ‘Query’ fever, was first identified in Australia in the 1930s as workers at a meat processor developed fevers. The cause was unknown, leading to the diagnosis of ‘Query fever’, since abbreviated to Q fever.
What is Q fever?
Coxiella burnetii is an obligate intracellular bacterial pathogen that causes Q fever in humans. It is found in a variety of domestic and wild animals, which may not display signs of infection. In Australia, it is maintained in the bush by local species and their ticks. According to the Q fever information site, the infected animal will excrete large amounts of the organism in its urine, faeces, and milk, as well as birth fluids and uterine discharges following birth.
The key feature of the pathogen is its “ability to withstand harsh environmental conditions”. For example, it has been shown to remain infective for up to 9 months at 15-20 degrees C on wool. Furthermore, infected tick faeces demonstrated its ability to “remain infectious, in a dried state” for around 2 years.
Symptoms can be negligible or more severe, including fever, weight loss, and chronic fatigue. In some instances, it has led to liver inflammation, or inflammation of the membrane around the brain or spinal cord, and lung issues.
Recent cause for concern
The Guardian reported in September that an “increase in the number of Q fever cases” sparked calls for residents who work with animals to get vaccinated. An increase of cases from the “usual 3 to 7” up to 11 so far this year has prompted concern. Although person-to-person transmission is “rare”, vaccination is being promoted among those working in “high-risk industries” such as farmers, veterinarians, wildlife workers, and breeders.
Dr Josette Chor of the Wide Bay public health unit indicated that the recent increase may be due to more wildlife near residential areas. As well as domestic and wild animal species, she referred to “the general environment”, where the pathogen can “persist”.
“There is an effective vaccine available to protect people against Q fever…Vaccination is recommended for all people who are working in, or intend to work in, a high-risk occupation.”