Vergara Andrea, Montalvo Tomás, Sabaté Sara, Villanueva-Cañas José Luis, Vilanova David, Planell Raquel, Roca Ignasi, Ballesté Clara, Hurtado Juan Carlos, Figuerola Jordi, González Raquel, Vila Jordi
Department of Microbiology, Hospital Clínic-CDB, University of Barcelona, Barcelona, Spain; Institute of Global Health (ISGlobal), Barcelona, Spain; CIBER Enfermedades Infecciosas (CIBERINFEC), Instituto Salud Carlos III, Madrid, Spain.
Agencia de Salut Pública de Barcelona, Barcelona, Spain; Institut d'Investigació Biomèdica Sant Pau (IIB Sant Pau), Barcelona, Spain; CIBER Epidemiologia y Salud Pública (CIBERESP), Instituto Salud Carlos III, Madrid, Spain.
J Infect Public Health. 2025 Oct;18(10):102933. doi: 10.1016/j.jiph.2025.102933. Epub 2025 Aug 21.
A better understanding of Salmonella epidemiology at the human-wildlife interface, emphasizing the importance of One Health strategies in controlling zoonotic disease transmission is needed. This study aimed to investigate the epidemiological relationship between Salmonella spp. isolated from wild-living birds and human patients in Barcelona, Spain.
The presence of Salmonella spp. was tested in faecal samples of young specimens of Yellow-legged gull (Larus michahellis, n = 129), Audouin's gull (Ichthyaetus audouinii, n = 97), and pigeon (Columba livia, n = 324) specimens. Similarly, 36 isolates of S. enterica serovar Typhimurium were collected from human patients. The isolates were characterised by chromosomal DNA analysis using pulsed-field gel electrophoresis (PFGE) or whole-genome sequencing.
All Salmonella isolates recovered from the bird samples were identified as S. enterica serovar Typhimurium with an overall prevalence of 3.1 % (17/550). Twelve isolates were recovered from 129 Yellow-legged gulls (9.3 %), 3 from 97 Audouin's gulls (3.1 %), and 2 from 324 pigeons (0.6 %). In total, 25/36 (69.5 %) human and 9/17 (52.9 %) bird samples were identified as monophasic species. The PFGE strain typing results with XbaI grouped S. Typhimurium monophasic isolates into eight different clusters. Three pairs of strains (one from a human and one from a seagull) were subjected to whole-genome sequencing. All strains belonged to the same sequence type (ST34), and sequencing data confirmed that all strains analysed corresponded to the monophasic variant of S. Typhimurium and that both 13_13995 (Audouin's gull isolate) and 14_28806 (human isolate) strains were different in only 4 SNPs. The following acquired resistance genes were found in sequenced strains: aph(3'')-Ib, aph(6)-Id, bla, sul2 and tet(B).
Our results indicate that seagulls may act as reservoirs for S. Typhimurium and pose a potential risk of transmission to humans.
需要更好地了解人类与野生动物界面的沙门氏菌流行病学，强调“同一健康”策略在控制人畜共患病传播中的重要性。本研究旨在调查西班牙巴塞罗那从野生鸟类和人类患者中分离出的沙门氏菌属之间的流行病学关系。
检测了黄腿鸥（Larus michahellis，n = 129）、奥杜邦鸥（Ichthyaetus audouinii，n = 97）和鸽子（Columba livia，n = 324）幼体粪便样本中沙门氏菌属的存在情况。同样，从人类患者中收集了36株肠炎沙门氏菌血清型鼠伤寒菌株。使用脉冲场凝胶电泳（PFGE）或全基因组测序通过染色体DNA分析对分离株进行鉴定。
从鸟类样本中分离出的所有沙门氏菌分离株均被鉴定为肠炎沙门氏菌血清型鼠伤寒，总体患病率为3.1%（17/550）。从129只黄腿鸥中分离出12株（9.3%），从97只奥杜邦鸥中分离出3株（3.1%），从324只鸽子中分离出2株（0.6%）。总共，25/36（69.5%）的人类样本和9/17（52.9%）的鸟类样本被鉴定为单相菌株。用XbaI进行的PFGE菌株分型结果将单相鼠伤寒沙门氏菌分离株分为八个不同的簇。对三对菌株（一对来自人类，一对来自海鸥）进行了全基因组测序。所有菌株属于同一序列类型（ST34），测序数据证实所有分析的菌株均对应于鼠伤寒沙门氏菌的单相变体，并且13_13995（奥杜邦鸥分离株）和14_28806（人类分离株）菌株仅在4个单核苷酸多态性上不同。在测序菌株中发现了以下获得性耐药基因：aph(3'')-Ib、aph(6)-Id、bla、sul2和tet(B)。
我们的结果表明，海鸥可能是鼠伤寒沙门氏菌的储存宿主，并对人类构成潜在的传播风险。
