Q Fever

Coxiella burnetii
Phylum	Proteobacteria
Class	Zymobacteria
Sub-class	Alphaproteobacteria
Order	Legionellales
Family	Coxiellaceae
Genus	Coxiella
Species	C. burnetii

Goat placenta from Q fever abortion. Note the thickened intracotyledonary areas and tan exudate. The cotyledons have tan necrotic margins and congested, red centres. Copyright CFSPH Iowa State.

Q fever

• Caused by Coxiella burnetti
• Influenza-like disease of humans in contact with farm animals
• Transmitted to humans by inhalation from parturient sheep, goats and cattle
• Organisms replicate in female genital tract and mammary glands of ruminants
• Shedding occurs in uterine discharges, foetal fluid and milk
• Infections in animals usually subclinical
• Sporadic abortions occur in sheep, goats, cattle, cats
• Infertility may result in ruminants, as well as placentitis or endometritis
• Hepatitis, myocarditis and interstitial pneumonia may occur in affected foetuses
• Diagnosis: MZN-stained smears of placental tissue and uterine discharges; immunofluorescence; PCR; culture; serology
• Control: disposal of infected placenta and separation of pregnant ruminants; inactivated vaccines

Coxiella burnetti (rickettsia) Infection by inhalation, ingestion or tick bites. Leads to late abortion or birth of weak lambs/kids. See a thickened leathery placenta covered in exudate. ZN stains can be use to demonstrate organisms.