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Fourtune, L.

Publications and source records attributed to Fourtune, L..

5 recordsLinked to original sources
bioRxiv2026

Territorial risk of high pathogenicity avian influenza in France is associated with farmed species diversity

Animal infectious diseases threaten food security, livestock production and public health. While disease prevention strategies typically target risk factors associated with high-competence hosts or environmental conditions, we hypothesise that lower-competence species can reduce disease risk by diluting effective contact rates between farms. Using spatial statistical models calibrated on three successive French high pathogenicity avian influenza (HPAI) epidemics (2020-2023), we show that greater local diversity of livestock farms, including cattle and pig farms, is associated with significantly lower HPAI risk. Moreover, we show that the positive association between duck houses and HPAI risk weakens as the number of less-competent non-duck poultry houses increases, revealing a dilution effect within poultry production systems. These findings suggest that livestock diversity is a previously overlooked determinant of disease spread and open new research avenues on territorial diversification to complement traditional approaches for the long-term control of high-impact animal infectious diseases.

ecology↗
bioRxiv2025

Highly pathogenic avian influenza management in high-density poultry farming areas

The continuous spread of highly pathogenic avian influenza H5 viruses poses significant challenges, particularly in regions with high poultry farm densities where conventional control measures are less effective. Using phylogeographic and phylodynamic tools, we analysed virus spread in Southwestern France in 2020-21, a region with recurrent outbreaks. Following a single introduction, the virus spread regionally, mostly affecting duck farms, peaking in mid-December with a velocity of 27.8 km/week and an effective reproduction number between farms (Re) of 3.8, suggesting the virus can spread beyond current control radii. Transmission declined after late December following preventive culling. Farm infectiousness was estimated around 9 days. Duck farm density was the main driver of virus spread and we identified farm density and proximity thresholds required to maintain effective control (Re < 1). These findings offer actionable guidance to support regional biosecurity and to improve the robustness of the poultry sector to mitigate future outbreaks.

evolutionary biology↗
bioRxiv2022

Two major epidemics of highly pathogenic avian influenza virus H5N8 and H5N1 in domestic poultry in France, 2020-2022

The spread of highly pathogenic avian influenza (HPAI) viruses worldwide has serious consequences for animal health and a major economic impact on the poultry production sector. Since 2014, Europe has been severely hit by several HPAI epidemics, with France being the most affected country. Most recently, France was again affected by two devastating highly pathogenic avian influenza epidemics in 2020-21 and 2021-22. We conducted a descriptive analysis of the 2020-21 and 2021-22 epidemics, in a first step towards identifying the poultry sectors remaining vulnerabilities regarding HPAI viruses in France. We examined the spatio-temporal distribution of outbreaks that occurred in France in 2020-21 and 2021-22, and we assessed the outbreaks spatial distribution in relation to two High-Risk Zones recently incorporated into French legislation to strengthen HPAI prevention and control. There were 468 reported outbreaks during the 2020-21 epidemic, and 1,223 outbreaks during the 2021-22 epidemic. In both epidemics, most outbreaks (80.6% and 74.0%) were located into the two High-Risk Zones. The southwestern High-Risk Zone was affected in both epidemics, while the western High-Risk Zone was affected for the first time in 2021-22, explaining the extremely high number of outbreaks reported. We showed that the spatial distribution model used to create the two High-Risk Zones was able to predict the location of outbreaks for the 2020-21 and 2021-22 epidemics. These zones were characterized by high poultry farm densities; future efforts should therefore focus on reducing the density of susceptible poultry in highly dense areas.

ecology↗
bioRxiv2018

Intraspecific genetic and phenotypic diversity: parallel processes and correlated patterns?

Intraspecific diversity plays a key role for evolutionary and ecological dynamics. It is the raw material on which acts selection, it improves species and communities resilience to disturbance and it affects the way species modulate their biotic and abiotic environment. Understanding patterns and underlying determinants of genetic and phenotypic intraspecific diversity is therefore of critical importance for ecological, evolutionary and conservation sciences. Here, focusing on two freshwater fish species (Gobio occitaniae and Phoxinus phoxinus) sampled across a large river basin (the Garonne-Dordogne river basin, France), we used causal analyses to test for genetic-phenotypic intraspecific diversity correlations (GPIDCs) and unravel the processes underlying intraspecific diversity patterns. Genetic diversity was assessed using microsatellite markers and phenotypic diversity was assessed through geometric morphometrics. We found disparities in the distribution of genetic and phenotypic diversity in the two species, suggesting higher level of local adaptation in G. occitaniae, and our results revealed common and contrasted processes shaping diversity at the - and {beta}-level. At the -level, we found no GPIDC in both species despite common relations between isolation and genetic and phenotypic -diversity in G. occitaniae. At the {beta}-level, we found no GPIDC in P. phoxinus but we found a positive GPIDC in G. occitaniae. This correlation appeared to be caused by a direct impact of one facet of intraspecific diversity on the other, and we speculated that it could originate from positive assortative mating. Studying neutral genetic diversity and phenotypic diversity within an integrative framework appears as a valuable way of deciphering the complex and diverse impacts of neutral and adaptive processes on intraspecific diversity patterns.

evolutionary biology↗