Search results for "Arachnid Vectors"
showing 9 items of 9 documents
Competition between strains of Borrelia afzelii inside the rodent host and the tick vector
2018
Multiple-strain pathogens often establish mixed infections inside the host that result in competition between strains. In vector-borne pathogens, the competitive ability of strains must be measured in both the vertebrate host and the arthropod vector to understand the outcome of competition. Such studies could reveal the existence of trade-offs in competitive ability between different host types. We used the tick-borne bacteriumBorrelia afzeliito test for competition between strains in the rodent host and the tick vector, and to test for a trade-off in competitive ability between these two host types. Mice were infected via tick bite with either one or two strains, and these mice were subse…
Epidemiology and clinical features of Mediterranean spotted fever in Italy
2006
Mediterranean Spotted Fever is caused by Rickettsia conorii and is transmitted to humans by Rhipicephalus sanguineus, the common dog tick. It is characterized by the symptomatologic triad: fever, exanthema and "tache noire", the typical eschar at the site of the tick bite. In Italy the most affected region is Sicily. The seasonal peak of the disease (from June through September) occurs during maximal activity of immature stage ticks. Severe forms of the disease have been reported in 6% of patients, especially adults with one of the following conditions: diabetes, cardiac disease, chronic alcoholism, glucose-6-phosphate dehydrogenase deficiency, end stage kidney disease. The mortality rate m…
[Mediterranean spotted fever in paediatric and adult patients: two clinical aspects of the same disease].
2012
Mediterranean Spotted Fever is an acute febrile disease caused by Rickettsia conorii and transmitted to humans by the brown dog tick Rhipicephalus sanguineus. Nearly 400 cases are reported every year in Sicily, mainly from June to September. The aim of this study is to compare the clinical and laboratory features of two different groups of patients , one of adults and one of children. The analysis included all adult patients with MSF diagnosed at the Institute of Infectious Diseases, Paolo Giaccone University Polyclinic in Palermo, during the period January 2007- August 2010 and all the children diagnosed with MSF at the G. Di Cristina Children Hospital in Palermo during the period January …
Detection of tick-borne encephalitis virus in I. ricinus ticks collected from autumn migratory birds in Latvia.
2014
Birds have a potential of spreading ticks via bird migration routes. In this study, we screened 170 ticks removed during autumn 2010 from 55 birds belonging to 10 species for the presence of tick-borne encephalitis virus (TBEV). In total, TBEV RNA was detected in 14% of I. ricinus tick samples obtained from different birds species. The results of this study indicate the possible role of migrating birds in the dispersal of TBEV-infected ticks along the southward migration route.
Prevalence of Borrelia burgdorferi in Ixodes ricinus ticks collected from moose (Alces alces) and roe deer (Capreolus capreolus) in southern Norway
2010
As part of a larger survey, ears from 18 roe deer (Capreolus capreolus) and 52 moose (Alces alces) shot in the 2 southernmost counties in Norway were collected and examined for Ixodes ricinus ticks. Seventy-two adult ticks, 595 nymphs, and 267 larvae from the roe deer, and 182 adult ticks, 433 nymphs, and 70 larvae from the moose were investigated for infection with Borrelia burgdorferi sensu lato (s.l.). The results showed the presence of B. burgdorferi s.l. DNA in 2.9% of the nymphs collected from roe deer and in 4.4% of the nymphs and 6.0% of the adults collected from moose. The spirochetes were not detected in adult ticks from roe deer, or in larvae feeding on roe deer or moose. In comp…
Tick-borne bacteria in Ixodes ricinus collected in southern Norway evaluated by a commercial kit and established real-time PCR protocols
2015
Ticks are important vectors of human pathogens. The knowledge of disease causing agents harboured by ticks in Norway is limited. The focus of this study was (a) to detect the bacteria of medical importance in ticks collected from the vegetation at locations in the southern part of the country and (b) to evaluate a novel commercially available multiplex PCR based method by comparing results with conventional established real-time PCR protocols. Borrelia burgdorferi sensu lato was confirmed to be the most prevalent pathogen detected (31%) among one hundred individually analysed adult ticks. Borrelia miyamotoi, a spirochete associated with relapsing fever, was detected in one sample. Anaplasma…
Israeli Spotted FeverRickettsiain SicilianRhipicephalus sanguineusTicks
2003
To the Editor: Mediterranean spotted fever (MSF) is endemic in Italy, where it is a reportable disease. From 1992 to 1998, the Italian Ministry of Health was notified of approximately 8,500 cases of human rickettsioses presumed to be MSF. MSF occurs more commonly in some central (Lazio) and southern (Sardinia, Sicily, and Calabria) regions (1,2); in 1998, an average of 8.8 cases occurred for every 100,000 persons in Sicily, compared with the national average of 1.6 cases per 100,000 persons. Rickettsia conorii has been thought to be the only pathogenic Rickettsia of the spotted fever group in Sicily (3,4) or the western Mediterranean area. Recently, three different spotted fever group ricke…
Prevalence of tick-borne pathogens in ticks collected from migratory birds in Latvia.
2014
Migratory birds act as hosts and long-distance vectors for several tick-borne infectious agents. Here, feeding Ixodes ticks were collected from migratory birds during the autumn migration period in Latvia and screened for the presence of epidemiologically important non-viral pathogens. A total of 93 DNA samples of ticks (37 larvae and 56 nymphs) removed from 41 birds (order Passeriformes, 9 species) was tested for Lyme borreliosis spirochaetes, Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp. Borrelia burgdorferi DNA was detected in 18% of the tick samples, and a majority of infected ticks were from thrush (Turdus spp.) birds. Among the infected ticks, Borrelia valaisiana was de…
Rodent host population dynamics drive zoonotic Lyme Borreliosis and Orthohantavirus infections in humans in Northern Europe
2021
Zoonotic diseases, caused by pathogens transmitted between other vertebrate animals and humans, pose a major risk to human health. Rodents are important reservoir hosts for many zoonotic pathogens, and rodent population dynamics affect the infection dynamics of rodent-borne diseases, such as diseases caused by hantaviruses. However, the role of rodent population dynamics in determining the infection dynamics of rodent-associated tick-borne diseases, such as Lyme borreliosis (LB), caused by Borrelia burgdorferi sensu lato bacteria, have gained limited attention in Northern Europe, despite the multiannual abundance fluctuations, the so-called vole cycles, that characterise rodent population d…