Salmonella and Listeria spp. carriage by gulls (larids)

• Author(s): Duarte, Elsa Leclerc ; Guerra, Maria Manuela ; Bernardo, Fernando Manuel
• Date: 2010
• Persistent ID: http://hdl.handle.net/10174/1965
• Origin: Repositório Científico da Universidade de Évora
• Subject(s): Larídeos; Salmonella sp.; Listeria sp.
• Document Type: Journal article
• Language: English

Description

As in other countries, the population of gulls (Laridae) has been increased exponentially in Portugal. To evaluate the public health implications of this development, two hundred and eighty-five samples of gulls’ faeces were investigated for two bacteria species of zoonotic importance, Salmonella spp. and Listeria sp. Thirty-seven (13.0 %) samples were positive for Salmonella spp. Amongst these, teh most common serovars were Salmonella Typhimurium (37.8%) and Salmonella Derby (18.9%). Simultaneously presence of two different serovars was detected in six samples. Twenty four different antibioresistance profiles were detected in Salmonella sp. isolates (68.7%).Phage-types found for Salmonella Typhimurium 5+ were PT 12 and U302. Listeria spp. were present in twenty-eight (9.8%) samples, seventeen of which had Listeria monocytogenes (6.0%). Other species isolated were Listeria seeligeri (0.7%), L. innocua (5.3%), and L.welshimeri (0.7%). Seven samples were co-contaminated with two or more species. A combination of serotyping, phage-typing, cadmium and arsenic sensitivities were used to subtype 18 of the L. monocytogenes isolates recognising at least 10 different strains. Both bacterial genera were simultaneously isolated from twelve samples (4.2%). Several epidemiological explantion and the possible significance as markers waste management in the geographical area studied are discussed.