All Posts Tagged With: "Anaplasma"

Excerpt:

Among the 20 tick species described in Switzerland, Ixodes ricinus, the most
frequent one, is implicated in the transmission of pathogenic agents. Lyme
borreliosis and tick-borne encephalitis (TBE) are the major tick-borne
diseases transmitted to human. 
**Presently 5 Borrelia species, belonging to the group Borrelia burgdorferi,
are recognized as human pathogens**. 
The risks of infection depend on the stage of the vector, the multiple
hosts, the pathogenic agent, as well as human behavior in nature. 
The detection of other pathogenic agents in ticks: Anaplasma, Babesia and
Rickettsia predispose to infections or co-infections. Results of
sero-epidemiologic studies suggest human infections. Active surveillance by
physicians is necessary and clinical studies are required to evaluate the
importance of these infections in Switzerland.

Full article: http://www.parasitesandvectors.com/content/3/1/42

Excerpt:

Lizards are considered zooprophylactic for almost all Borrelia burgdorferi species, and act as dilution hosts in parts of North America. Whether European lizards significantly reduce the ability of B. burgdorferi to maintain itself in enzootic cycles, and consequently decrease the infection rate of Ixodes ricinus ticks for B. burgdorferi and other tick-borne pathogens in Western Europe is not clear.

Results

Ticks were collected from sand lizards, their habitat (heath) and from the adjacent forest. DNA of tick-borne pathogens was detected by PCR followed by reverse line blotting. Tick densities were measured at all four locations by blanket dragging. Nymphs and adult ticks collected from lizards had a significantly lower (1.4%) prevalence of B. burgdorferi sensu lato, compared to questing ticks in heath (24%) or forest (19%). The prevalence of Rickettsia helvetica was significantly higher in ticks from lizards (19%) than those from woodland (10%) whereas neither was significantly different from the prevalence in ticks from heather (15%). The prevalence of Anaplasma and Ehrlichia spp in heather (12%) and forest (14%) were comparable, but significantly lower in ticks from sand lizards (5.4%). The prevalence of Babesia spp in ticks varied between 0 and 5.3 %. Tick load of lizards ranged from 1 – 16. Tick densities were ~ 5-fold lower in the heather areas than in woodlands at all four sites.

The use of new, highly sensitive diagnostic methods has revealed persistent
infections to be a common feature of different tick-borne diseases, such as
babesiosis, anaplasmosis and heartwater. Antigenic variation can contribute to
disease persistence through the continual elaboration of new surface structures,
and we know in several instances how this is achieved. Continued