Seabirds (Laridae) as a source of Campylobacter spp., Salmonella spp. and antimicrobial resistance in South Africa

• Published in: Environmental microbiology 2017-10, Vol.19 (10), p.4164-4176
• Main Authors: Moré, Elisabet, Ayats, Teresa, Ryan, Peter G., Naicker, Preneshni R., Keddy, Karen H., Gaglio, Davide, Witteveen, Minke, Cerdà‐Cuéllar, Marta
• Format: Article
• Language: English
• Subjects: Analytical methods; Animals; Anti-Bacterial Agents - pharmacology; Antiinfectives and antibacterials; Antimicrobial agents; Antimicrobial resistance; Aquatic birds; Bacteria; Bird Diseases - epidemiology; Bird Diseases - microbiology; Campylobacter; Campylobacter - classification; Campylobacter - drug effects; Campylobacter - isolation & purification; Campylobacter Infections - epidemiology; Campylobacter Infections - microbiology; Campylobacter Infections - transmission; Charadriiformes - microbiology; Chicks; Colonies; Drug resistance; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Gastroenteritis; Gel electrophoresis; Gels; Genotypes; Humans; Juveniles; Kelp; Microbial Sensitivity Tests; Microbiological strains; Multidrug resistance; Public health; Pulsed-field gel electrophoresis; Quinolones; Salmonella; Salmonella enterica - classification; Salmonella enterica - drug effects; Salmonella enterica - isolation & purification; Salmonella Infections - epidemiology; Salmonella Infections - microbiology; Salmonella Infections - transmission; Salmonellosis; Seabirds; South Africa - epidemiology; Tetracyclines; Thermophilic bacteria; Zoonoses
• ISSN: 1462-2912; 1462-2920
• DOI: 10.1111/1462-2920.13874

Summary Zoonotic thermophilic Campylobacter and nontyphoidal Salmonella enterica are a major cause of foodborne human gastroenteritis worldwide. There is little information about reservoirs of these zoonotic agents in Africa. Thus, chicks of kelp gulls (Larus dominicanus, n = 129) and greater crested terns (Thalasseus bergii, n = 100) were studied at five colonies on the Western Cape coast (South Africa) during summer 2013/2014. Campylobacter spp. occurrence was 14.0% (CI95%: 9.9–19.3), with C. jejuni the most frequently isolated species, whilst that of Salmonella was 27.5% (CI95%: 21.9–33.9) overall, with a higher prevalence in gulls (43.0%, CI95%: 34.8–52.4) than terns (7.0%, CI95%: 3.1–14.4). Among the 16 different S. enterica serovars found, Anatum, Enteritidis and Hadar were the most frequent. The same or highly similar pulsed‐field gel electrophoresis genotype was found in some Salmonella isolates from seabirds and humans presenting with salmonellosis in Cape Town hospitals. Both Campylobacter and Salmonella isolates exhibited antimicrobial resistance to several agents, including critically important antimicrobials (quinolones, tetracyclines and β‐lactams) and multidrug resistance in Salmonella serovars from kelp gulls. Our results highlight the importance of seabirds as reservoirs of Campylobacter and Salmonella resistant strains and their role in the maintenance and transmission of these bacteria in the environment, with implications for public health.