Q fever is the zoonotic disease caused by infection with the bacteria Coxiella burnetti.This bacteria is endemic in domestic animals throughout the world, with the exception of New Zealand, and there is an increasing awareness of the role of wildlife in the maintenance of this disease.
The disease has been best characterized in domestic ruminants including sheep, goatsand cattle but has the potential to infect a wide range of wild and domestic species including cats and dogs.
There are recent reports of infection or exposure to the bacteria being detected in a range of European wildlife species including species of migratory birds in Cyprus, wild deer and wild sheep in the Czech republic, Slovakia and Spain, bison in Poland,brown rats in the UK, and wild rabbits, hares, wild boar and birds of prey in Spain.In the Netherlands C. burnettiinfection has been found inroe deer investigated by the DWHC.
Humans can also be infected with this bacteria.
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Infection with this bacteria can be subclinicalbutcan cause acute disease in some animals.
C. burnettibacteria has an affinity for the mammary glands and placenta and infected pregnant animals may abort or deliver still-born young. These animals may show a period offever and appetite loss but tend to recover spontaneously despite remaining persistently infected, potentially shedding the bacteria in milk, birthing fluids, urine and feces. When antibodies are present, re-infection or re-emergence of latent infection may be subclinical.
Infected cats may have a short period of fever, appetite loss and apathy.
Infectious Diseases of Wild Mammals and Birds in Europe (1). Somerset, GB: Wiley-Blackwell, 2012. ProQuest ebrary. Web. 6 October 2016.
Animals are typically infected via direct contact with other infected animals orindirectly by contact with food or beddingcontaminated with infectious particles. Spread of aeorsolised infectious particles on the wind is also an important route of infection. In addition, the bacteria has also been found in several species of ticks and it is believed that tick bites are another potential route of infection.
The majority of people who become infected will experience no or only mild signs of disease oneto three weeks after exposure and will often recover without requiring treatment. Those who do become ill in the acute phase may show vague signs of illness including headaches, muscle pain, night sweats and fever; an atypical pneumonia is also described in some patients. In pregnant women it can result in abortion. Treatment is usually effective in clearing the infection however, complications can occur. In addition, some individuals may develop chronic disease only manifesting years after the infection; symptoms caninclude infection of the heart, joints and liver.
McQuiston, Jennifer H., James E. Childs, and Herbert A. Thompson. “Zoonosis Update.” AVMA
Infection withC.burnetti occurs predominantly via inhalation of infectious airbourne particles for example downwind of sites where infected animals are kept. The people who are most at risk of inhaling or ingesting infectious particles are those who come into close contact with infected animals, particularly placentas or birthing fluids insheep and goat lambing operations. The organism can be shed in the milk of infected animals but is effectively killed by the pasteurization process. Whilst ticks are believed to play a role in the circulationof disease in other animals species, it is not thought thatthey play an important role in the transmission of disease to humans.
This bacteria is endemic in domestic and some wild animal populations throughout the world, with the exception of New Zealand where, as of 2012, there was no evidence of infection.
Standard hygiene measures should be observed by people who come into close contact with the high-risk species. To this end, protective equipment including face masks are advisable to minimise exposure to small droplets and aerosolised infectious particles. Farmers can minimize the risk of animal to animal spread by ensuring the appropriate removal of aborted materials, regular testing of blood or milk samples as well as post-morteminvestigation of still-born animals, and thorough disinfection of areas used for lambing.
