{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T17:44:40Z","timestamp":1785433480513,"version":"3.56.0"},"reference-count":37,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T00:00:00Z","timestamp":1782432000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100019370","name":"Foundation for Science and Technology","doi-asserted-by":"publisher","award":["UID\/00772\/2025"],"award-info":[{"award-number":["UID\/00772\/2025"]}],"id":[{"id":"10.13039\/501100019370","id-type":"DOI","asserted-by":"publisher"}]},{"award":["UID\/00772\/2025"],"award-info":[{"award-number":["UID\/00772\/2025"]}],"id":[{"id":"https:\/\/ror.org\/00snfqn58","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Tularemia is a zoonotic disease caused by the highly contagious bacterium Francisella tularensis, with rabbits, hares, and rodents considered as primary reservoirs. Clinical manifestations in humans can range from mild to life-threatening, depending on the mode of exposure (ingestion, inhalation, skin contact, injection, or tick bite), with high fever being a common feature. The primary aim of the present research was to evaluate the circulation of F. tularensis and the potential infection among wild boar (Sus scrofa) and red deer (Cervus elaphus) from the central region of Portugal. A total of 368 samples (including serum and organ samples) were collected from 184 wild boar and 184 red deer. For serological analysis, two commercially available enzyme-linked immunosorbent assay (ELISA) kits were used to detect immunoglobulin M (IgM) and G (IgG) antibodies to F. tularensis. Antibodies to F. tularensis (IgG and IgM) were detected in one adult male wild boar, corresponding to a seroprevalence of 0.54% (1\/184, 95% confidence interval [95% CI]: 0.01\u20133.0%). No antibodies to F. tularensis were detected in red deer. Molecular detection by PCR was negative in the seropositive animal, in which submandibular lymph node, liver, and spleen samples were analysed targeting the 16S rRNA gene. These findings indicate exposure of wild boar to F. tularensis in central Portugal, suggesting a sporadic presence of the pathogen. Although no evidence of active infection was detected in the analysed tissues, the presence of seropositive individuals highlights the need for further investigation. Despite the very low seroprevalence observed, the zoonotic potential of F. tularensis supports the importance of continued surveillance within a One Health perspective.<\/jats:p>","DOI":"10.3390\/pathogens15070675","type":"journal-article","created":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T05:52:11Z","timestamp":1782453131000},"page":"675","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Very Low Serological Evidence of Exposure to Francisella spp. in Wild Boar and Red Deer from Central Portugal"],"prefix":"10.3390","volume":"15","author":[{"given":"Humberto","family":"Pires","sequence":"first","affiliation":[{"name":"Polytechnic Institute of Castelo Branco (IPCB), 6000-909 Castelo Branco, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8857-4038","authenticated-orcid":false,"given":"S\u00f3nia","family":"Saraiva","sequence":"additional","affiliation":[{"name":"Animal and Veterinary Research Centre (CECAV), University of Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Vila Real, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9584-6636","authenticated-orcid":false,"given":"Manuela","family":"Matos","sequence":"additional","affiliation":[{"name":"Centre for the Research and Technology of Agro-Environmental and Biological Science (CITAB), University of Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, 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Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5433-4258","authenticated-orcid":false,"given":"Cristina","family":"Pintado","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Castelo Branco (IPCB), 6000-909 Castelo Branco, Portugal"},{"name":"Centre Research for Natural Resources, Environment and Society (CERNAS-IPCB), 6001-909 Castelo Branco, Portugal"},{"name":"ICBAS\u2014School of Medicine and Biomedical Sciences, Porto University, 4050-313 Porto, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lu\u00eds","family":"Figueira","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Castelo Branco (IPCB), 6000-909 Castelo Branco, Portugal"},{"name":"ICBAS\u2014School of Medicine and Biomedical Sciences, Porto University, 4050-313 Porto, 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