Q fever in a Queensland meatworks

Area of Science:

• Veterinary Epidemiology
• Infectious Diseases
• Occupational Health

Background:

• Q fever is an infectious disease caused by Coxiella burneti.
• Meatworks environments present unique occupational health risks.
• Previous studies indicated cattle as the primary source of Q fever in meat processing facilities.

Purpose of the Study:

• To investigate the epidemiology of Q fever in a Brisbane meatworks.
• To identify sources and transmission routes of Coxiella burneti.
• To analyze factors contributing to a Q fever outbreak in 1969.

Main Methods:

• Retrospective epidemiological study over 10 years (1968-1977).
• Analysis of incidence rates and seasonal distribution.
• Serological survey of meatworks employees.
• Investigation of outbreak-specific contributing factors.

Main Results:

• Average annual Q fever incidence was 1%, with a significant outbreak (7.9%) in 1969.
• Cattle were the main source, with highest risk on the cattle slaughter floor.
• The 1969 outbreak showed increased incidence in small stock workers and non-meat handlers.
• Inhalation of infectious dust/aerosols was the primary transmission route.
• Serological survey revealed a 15.8% prevalence of Q fever antibodies among employees.

Conclusions:

• Cattle are the primary reservoir for Q fever in this meatworks.
• The 1969 outbreak suggests a potential role for sheep and/or swine.
• Inhalation is the predominant route for Q fever transmission in this setting.
• A significant proportion of infected individuals may remain asymptomatic.