Browsing by Issue Date, starting with "2017-10-02"
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- The role of wild leporids as reservoirs of infectious agentsPublication . Carvalho, Carina Luísa da Costa; Duarte, Elsa Leclerc; Duarte, Margarida; Zé-Zé, LíbiaThe European wild rabbit (Oryctolagus cuniculus) and the Iberian hare (Lepus granatensis), are keystones species in various ecosystems of the Iberian Peninsula and on the local game-based economy. This thesis aimed to investigate the rabbit haemorrhagic disease virus 2 (RHDV2), detected in Portugal in 2012 and currently disseminated in the continent and autonomous regions (Azores, Madeira, Berlengas). Given its alarming impact in the wild rabbit populations, the Portuguese Government has recently activated a plan aiming the control of the disease (Despatch 4757/2017 of May 31st). A second objective of this thesis was the epidemiological surveillance of Francisella tularensis zoonotic vector-borne pathogenic bacterium, with potential impact on Human Health. The Iberian hare is considered reservoir and potential sentinel species for this pathogen. Several methodologies were used to carry out the studies presented in this work, including basic pathology, microbiology and molecular methods. Data analysis involved the resource to phylogenetic inference, statistical programs and bioformatics (e.g. R software). This work enabled the development and validation of the first molecular diagnostic method for RHDV2, currently figuring in the OIE manual, and allowed insights into to the virus dynamic evolution in different epidemiologic and geographic contexts, widening the comprehension of RHDV2 phylogenetic relations among the strains that circulate in Portugal from 2012 until 2017. This study also made possible to ascertain the tularaemia epidemiologic situation in Portugal, confirming the role of wild leporids as reservoirs for the agent and enabling preliminary conclusions on Public Health risk in the country. Moreover, this work allowed confirming ticks as the main vectors for Francisella tularensis in Portugal. Globally, this work contributed to the state-of-the-art of both infections and produced relevant information that can be used to adjust the medical and sanitary prophylactic measures of both diseases to the present reality.
- Improving risk assessment of chemicals by the use of human biomonitoring - HBM4EU project activitiesPublication . Santonen, T.; Alvito, Paula; Bessems, J.; Borges, T.; Brunet, D.; Buekers, J.; Cornelis, C.; van Engelen, J.; Gonzalez Caballero, M.C.; Humar-Juric, T.; Heinälä, M.; Klaus, A.; Kononenko, L.; Krul, L.; Lamkarkach, F.; Louro, Henriqueta; Pronk, A.; Ormsby, J-N.; Viegas, S.; Rousselle, C.; Schaddelee-Scholten, B.; Silva, Maria João; Stierum, R.; Vinggaard, S A.M.; Vermeire, T.; Woutersen, M.The default approach in the risk assessment (RA) of chemicals is to assess external exposure by combining different sources and routes of exposure. This kind of approach contains various uncertainties and may overestimate exposure, since conservative estimates are needed due to the limited data on, for example, the absorption of the chemical and interspecies and intraspecies differences. Human biomonitoring (HBM) can help improve RA by providing measured data on combined exposures. In some cases, biomonitoring data can even provide a direct link to health effects. In some cases, biomonitoring allows to link exposure to specific contexts such as occupational settings. Although recent years have seen good examples of the use of biomonitoring in the risk assessment of chemicals, much work is still needed to improve its use in regulatory RA and human impact assessment (HIA). The European Human Biomonitoring Initiative (HBM4EU) was recently launched for fulfilling the gap between the exposure to hazardous chemical agents and their impact on human health. One of the aims of the HBM4EU project is to enhance the use of HBM data in RA and HIA of chemicals in different regulatory contexts including legislations on chemicals, plant protection products and biocides, as well as legislation on cosmetics, food safety and occupational safety. RA models for mixtures are also considered. Firstly, current RA practices are evaluated: is the use of biomonitoring integrated in the available RA guidance, and do given RA schemes have good examples of the advanced use of biomonitoring? A survey is also conducted to gather information from national regulatory risk assessors (in the EU, but also in non-EU countries) on their risk assessment practices, the use of HBM, and the obstacles and challenges related to its use. The challenges of the use of HBM data in RA may include a lack of guidance in the use of biomonitoring, a lack of knowledge regarding the interpretation of biomonitoring results, or the inability to link biomonitoring data to different exposure sources. Using a selected group of priority chemicals as example, we can determine whether these challenges can be overcome by including the recent HBM data, collected during the HBM4EU project, in the existing RA schemes. Finally, proposals will be made for the better use of HBM in RA and HIA in different policy domains.