Anaplasma Phagocytophilum - the Most Widespread Tick-Borne Infection in Animals in Europe

Abstract

The bacterium Anaplasma phagocytophilum (formerly Ehrlichia phagocytophila) may cause infection in several animal species including human. The disease in domestic ruminants is also called tick-borne fever (TBF), and has been known for at least 200 years. In Europe, clinical manifestations due to A. phagocytophilum have been recorded in sheep, goat, cattle, horse, dog, cat, roe deer, reindeer and human. However, seropositive and PCR-positive mammalian have been detected in several other species. Investigations indicate that the infection is prevalent in Ixodes ricinus areas in most countries in Europe. A. phagocytophilum infection may cause high fever, cytoplasmatic inclusions in phagocytes and severe neutropenia, but is seldom fatal unless complicated by other infections. Complications may include abortions, and impaired spermatogenesis for several months. However, the most important aspect of the infection at least in sheep is its implication as a predisposing factor for other infections. Factors such as climate, management, other infections, individual conditions etc. are important for the outcome of the infection. A. phagocytophilum may cause persistent infection in several species. Based on the 16S rRNA gene sequences several variants exist. Different variants may exist within the same herd and even simultaneously in the same animal. Variants may behave differently and interact in the mammalian host.

PCR detection of re-emerging tick-borne pathogen, Anaplasma phagocytophilum, in deer ked (Lipoptena cervi) a blood-sucking ectoparasite of cervids

“…Anaplasma phagocytophilum DNA and/or antibodies have been detected in humans (e.g., Chen et al 1994;Lotric-Furlan et al 1998;Blanco & Oteo 2002;Petrovec et al 1997;Kocianová et al 2008;Nováková et al 2010, etc. ) and in wide range of animals worldwide (e.g., Stuen et al 2003;Stuen et al 2007;Woldehiwet et al 2006). In Europe, red deer (Cervus elaphus) and roe deer (Capreolus capreolus) are considered as persistently infected with A. phagocytophilum and serve as the source of infection in natural foci (Liz et al 2002;Petrovec et al 2002;Polin et al 2004;Smetanová et al 2006;de la Fuente et al 2008;Štefanidesová et al 2008, etc.).…”

Infection of Ixodes spp. tick cells with different Anaplasma phagocytophilum isolates induces the inhibition of apoptotic cell death

“…This is one of the most prevalent tick-borne diseases in the United States (Goodman, 2005) while, although increasingly detected, it is still rare in Europe (Edouard et al, 2012). A. phagocytophilum is also an economically important pathogen of sheep in Europe where it causes tick-borne fever (TBF) (Stuen, 2007;Stuen et al, 2009). This disease has not been reported in the United States but cases of equine and canine granulocytic anaplasmosis caused by A. phagocytophilum have been recorded (Severo et al, 2015).…”

“…In the United States, the main vector is Ixodes scapularis, with a prevalence ranging from <1% to 50% (Goltz et al, 2013). In Europe, the main vector is Ixodes ricinus, with pathogen-prevalence ranging from <1% to 20% although it varies between geographical areas and stages of tick development (Stuen, 2007).…”

Toxoplasma gondii, Neospora caninum and tick-transmitted bacterium Anaplasma phagocytophilum infections in one selected goat farm in Slovakia

“…Moreover, infected animals are more sensitive to the infection with other pathogens. The clinical symptoms are represented by sudden high fever, inappetence, lower production yield, weight loss and abortions in pregnant ewes (Scott et al 1991;Stuen 2007). In Slovakia, the presence of A. phagocytophilum was detected previously in ticks and wild living animals (Šte-fančíková et al 2008;Štefanidesová et al 2008;Víchová et al 2010).…”