ESBL-producing Escherichia coli in Swedish gulls—A case of environmental pollution from humans?

Abstract

ESBL-producing bacteria are present in wildlife and the environment might serve as a resistance reservoir. Wild gulls have been described as frequent carriers of ESBL-producing E. coli strains with genotypic characteristics similar to strains found in humans. Therefore, potential dissemination of antibiotic resistance genes and bacteria between the human population and wildlife need to be further investigated. Occurrence and characterization of ESBL-producing E. coli in Swedish wild gulls were assessed and compared to isolates from humans, livestock and surface water collected in the same country and similar time-period. Occurrence of ESBL-producing E. coli in Swedish gulls is about three times higher in gulls compared to Swedish community carriers (17% versus 5%) and the genetic characteristics of the ESBL-producing E. coli population in Swedish wild gulls and Swedish human are similar. ESBL-plasmids IncF- and IncI1-type carrying ESBL-genes blaCTX-M-15 or blaCTX-M-14 were most common in isolates from both gulls and humans, but there was limited evidence of clonal transmission. Isolates from Swedish surface water harbored similar genetic characteristics, which highlights surface waters as potential dissemination routes between wildlife and the human population. Even in a low-prevalence country such as Sweden, the occurrence of ESBL producing E. coli in wild gulls and the human population appears to be connected and the occurrence of ESBL-producing E. coli in Swedish gulls is likely a case of environmental pollution.

High Colonization Rate and Heterogeneity of ESBL- and Carbapenemase-Producing Enterobacteriaceae Isolated from Gull Feces in Lisbon, Portugal

“…Our study revealed frequent occurrence of carbapenemase- and ESBL-producing Enterobacteriaceae (16% and 55%, respectively) colonizing gulls from the Lisbon coastline, Portugal. ESBL-producing Enterobacteriaceae among gulls were previously reported in USA [ 6 ], Canada [ 4 ], Chile [ 5 ], and in different countries in Europe [ 8 , 31 , 32 , 33 , 34 ], including Portugal in 2008 [ 12 , 13 ]. The high heterogeneity observed here in terms of bacterial species, ST, and resistance determinants showed that the high resistance rates observed were basically not simply consequences of shared microbiota between bird individuals, that could have biased our observation.…”

Antimicrobial resistant and extended‐spectrum β‐lactamase producing Escherichia coli in common wild bird species in Switzerland

“…Overall, five different STs were detected among the ESBL E. coli (Table ). The majority of these, including ST58, ST205, ST540, and ST1722, have already been reported in ESBL‐producing E. coli from waterfowl in Pakistan (Mohsin et al., ), gulls in Chile (Hernandez et al., ) Portugal (Guenther et al., ) and Sweden (Atterby et al., ). Interestingly, E. coli ST1193 belongs to extraintestinal pathogenic pandemic clonal group associated with urinary tract infections (UTIs) in humans and is, similar to the E. coli ST131 H30 clone, an important contributor to fluoroquinolone resistance worldwide (Tchesnokova et al., ).…”

Wildlife Is Overlooked in the Epidemiology of Medically Important Antibiotic-Resistant Bacteria

“…Some of the main anthropogenic sources of the AMR bacteria in wildlife already suggested were landfills, insufficiently treated wastewaters draining into rivers and lakes, and waste from intensively managed livestock farms (2,8). Several studies have proven that the bacterial genotypes found in wildlife in terms of sequence types and clinically relevant antibiotic resistance determinants resemble those found in humans and animals (10). Other reports found only a limited overlap in this regard, indicating that the horizontal transfer of genes via mobile genetic elements might play a more central role (11).…”