Publications by authors named "Laure Bournez"

Article Synopsis
  • Lyme borreliosis, transmitted by Ixodes ticks, is the most common zoonotic disease in the northern hemisphere, and a study was conducted in northeastern France from 2020 to 2022 to understand the factors influencing tick presence in private yards.
  • Citizen scientists collected ticks and assessed various yard and landscape features to determine their association with tick occurrences, particularly focused on the nymph stage of the Ixodes ricinus tick that primarily bites humans.
  • The study found that ticks were present in 32% of yards, with higher nymph presence in shaded areas and increased likelihood in yards with deer signs and brush piles, highlighting the need for public awareness about tick exposure in urban environments.
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Article Synopsis
  • Tick-borne encephalitis (TBE) outbreaks in Europe have been linked to the consumption of raw milk products, highlighting a need for better detection methods of the virus in these foods.
  • Researchers developed a sensitive cell culture-based method for detecting infectious TBEV in artificially contaminated raw goat milk and cheese, achieving varying levels of viral detection.
  • The study showed that this method successfully identified infectious TBEV in both milk and cheese samples, supporting its potential use in future foodborne outbreak investigations.
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The eco-epidemiology of tick-borne diseases hinges on the abundance and distribution of hosts that sustain tick populations and the pathogens they carry. Research into the role of bird species in the feeding of Ixodes ricinus ticks, the primary tick species of veterinary and public health importance in Europe, remains scarce. This study endeavors to bridge these knowledge gaps by (i) assessing the density of feeding ticks (DFT) within a bird community to pinpoint species making substantial contributions, and (ii) exploring interannual variations in DFT over an extended timeline.

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Background: Tick-borne encephalitis (TBE) is a severe human neuroinfection caused by TBE virus (TBEV). TBEV is transmitted by tick bites and by the consumption of unpasteurized dairy products from infected asymptomatic ruminants. In France, several food-borne transmission events have been reported since 2020, raising the question of the level of exposure of domestic ungulates to TBEV.

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Tick-borne flaviviruses and spp. are globally spread pathogens of zoonotic potential that are maintained by a transmission cycle at the interface between ticks and vertebrate hosts, mainly wild animals. Aside data on pathogen burden in ticks, information on the status of various hosts relative to infection is important to acquire.

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Article Synopsis
  • * Researchers conducted a study involving 40 European experts to identify and evaluate 59 potential drivers of TBE's emergence and rising incidence, categorizing them into eight domains.
  • * The top drivers identified include changes in human behavior, eating habits, landscape alterations, environmental factors like humidity and temperature, and the presence of various tick species and wildlife reservoirs.
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Birds play a role in maintaining tick-borne diseases by contributing to the multiplication of ticks and pathogens on a local scale during the breeding season. In the present study, we describe the diversity of tick and pathogen species of medical and veterinary importance in Europe hosted by 1040 captured birds (56 species) during their breeding season in France. Of the 3114 ticks collected, was the most prevalent species (89.

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Ixodes ricinus ticks (Acari: Ixodidae) are the most important vector for Lyme borreliosis in Europe. As climate change might affect their distributions and activities, this study aimed to determine the effects of environmental factors, i.e.

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Tick-borne encephalitis virus' (TBEV) geographic range and the human incidence are increasing throughout Europe, putting a number of non-endemic regions and countries at risk of outbreaks. In spring 2020, there was an outbreak of tick-born encephalitis (TBE) in Ain, Eastern France, where the virus had never been detected before. All patients but one had consumed traditional unpasteurised raw goat cheese from a local producer.

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The transmission of tick-borne encephalitis virus (TBEV) through food is rare, but can occur through the consumption of raw milk products from animals infected by tick bites. In 2020, France faced a TBEV outbreak linked to the consumption of unpasteurized goat cheese. The aim of this study was to develop and characterize a molecular method for the detection of TBEV in raw milk products based on the recent international standard PR ISO/DIS 16140-4.

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Mass-participation events in temperate forests are now well-established features of outdoor activities and represent high-risk activities regarding human exposition to tick bites. In this study we used a citizen science approach to quantify the space-time frequency of tick bites and undetected tick bites among orienteers that participated in a 6-day orienteering competition that took place in July 2018 in the forests of Eastern France, and we looked at the use and efficacy of different preventive behaviors. Our study confirms that orienteers are a high-risk population for tick bites, with 62.

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Tick-borne encephalitis virus (TBEV) depends mainly on a fragile mode of transmission, the co-feeding between infected nymphs and larvae on rodents, and thus persists under a limited set of biotic and abiotic conditions. If these conditions change, natural TBEV foci might be unstable over time. We conducted a longitudinal study over seven years in a mountain forest in Alsace, Eastern France, located at the western border of known TBEV distribution.

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A greater knowledge of the ecology of the natural foci of tick-borne encephalitis virus (TBEV) is essential to better assess the temporal variations of the risk of tick-borne encephalitis for humans. To describe the seasonal and inter-annual variations of the TBEV-cycle and the epidemiological parameters related to TBEV nymph-to-larva transmission, exposure of small mammals to TBEV, and tick aggregation on small mammals, a longitudinal survey in ticks and small mammals was conducted over a 3-year period in a mountain forest in Alsace, eastern France. TBEV prevalence in questing nymphs was lower in 2013 than in 2012 and 2014, probably because small mammals ( and ) were more abundant in 2012, which reduced tick aggregation and co-feeding transmission between ticks.

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Flaviviruses have become increasingly important pathogens in Europe over the past few decades. A better understanding of the spatiotemporal distribution of flaviviruses in France is needed to better define risk areas and to gain knowledge of the dynamics of virus transmission cycles. Serum samples from 1014 wild boar and 758 roe deer from 16 departments (administrative units) in France collected from 2009 to 2014 were screened for flavivirus antibodies using a competitive ELISA (cELISA) technique.

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Bluetongue is a vector-borne disease of ruminants with economic consequences for the livestock industry. Bluetongue virus serotype 8 (BTV-8) caused a massive outbreak in Europe in 2006/2009 and re-emerged in France in 2015. Given the unprecedented epidemiological features of this serotype in cattle, the importance of secondary routes of transmission was reconsidered and transplacental transmission of BTV-8 was demonstrated in naturally and experimentally infected cattle.

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Background: Ehrlichia ruminantium is the causal agent of heartwater, a fatal tropical disease affecting ruminants with important economic impacts. This bacterium is transmitted by Amblyomma ticks and is present in sub-Saharan Africa, islands in the Indian Ocean and the Caribbean, where it represents a threat to the American mainland.

Methods: An automated DNA extraction method was adapted for Amblyomma ticks and a new qPCR targeting the pCS20 region was developed to improve E.

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The disease, Heartwater, caused by the , represents a major problem for tropical livestock and wild ruminants. Up to now, no effective vaccine has been available due to a limited cross protection of vaccinal strains on field strains and a high genetic diversity of within geographical locations. To address this issue, we inferred the genetic diversity and population structure of 194 isolates circulating worldwide using Multilocus Sequence Typing based on , and .

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