Autor(es): Ferreira, Eduardo M ; Cunha, Monica ; Duarte, Elsa Leclerc ; Mira, António ; Pinto, Daniela ; Mendes, Inês ; Pereira, André C ; Pinto, Tiago ; Acevedo, Pelayo ; Santos, Sara M
Data: 2025
Identificador Persistente: http://hdl.handle.net/10174/38531
Origem: Repositório Científico da Universidade de Évora
Assunto(s): Transmission risk; tuberculosis; Mycobacterium bovis; Environmental contamination; Camera-Trapping
In many Mediterranean ecosystems, animal tuberculosis (TB), caused by Mycobacterium bovis, an ecovar of Mycobacterium tuberculosis complex (MTBC), is maintained by multi-host communities. It is hypothesised that interspecies transmission is mainly indirect via shared contaminated environments. Therefore, identifying spatial areas where MTBC bacteria occur and quantifying space use by susceptible hosts might help predict the spatial likelihood of transmission across the landscape. Here, we aimed to evaluate the transmission risk of MTBC in a multi-host system involving wildlife (ungulates and carnivores) and cattle (Bos taurus). We collected eighty-nine samples from natural substrates (water, soil, and mud) at 38 sampling sites in a TB endemic area within a Mediterranean agroforestry system in Portugal. These samples were analysed by real-time PCR to detect MTBC DNA. Additionally, host-specific space use intensity maps were obtained through camera-trapping covering the same sampling sites. Results evidenced that a significant proportion of samples were positive for MTBC DNA (49 %), suggesting that the contamination is widespread in the area. Moreover, they showed that the probability of MTBC occurrence in the environment was significantly influenced by topographic features (i.e., slope), although other non-significant predictor related with soil conditions (SMI: soil moisture index) incorporated the MTBC contamination model. The integration of host space use intensity maps with the spatial detection of MTBC showed that the red deer (Cervus elaphus) and wild boar (Sus scrofa) exhibited the highest percentages of high-risk areas for MTBC transmission. Furthermore, when considering the co-occurrence of multiple hosts, transmission risk analyses revealed that 26.5 % of the study area represented high-risk conditions for MTBC transmission, mainly in forest areas.
This study was funded by the Fundação para a Ciência e a Tecnologia (FCT), namely with a PhD grant [SFRH/BD/146037/2019; DOI: 10.54499/SFRH/BD/146037/2019] to EMF; EMF was also financed by MED (doi: 10.54499/UIDB/05183/2020) and CHANGE (doi:10.54499/LA/P/0121/2020) funds to PhD students. This work was also funded by FCT within the scope of MOVERCULOSIS project [2022.06014.PTDC] - Combining animal behaviour and movement to assess the influence of wildlife-livestock interactions on the spatio-temporal transmission risk of animal tuberculosis [https://doi.org/10.54499/2022.06014.PTDC
