Eurosurveillance - Volume 24, Issue 37, 12 September 2019

The occurrence of antibiotic resistance in faecal bacteria in sewage is likely to reflect the current local clinical resistance situation.

This observational study investigated the relationship between Escherichia coli resistance rates in sewage and clinical samples representing the same human populations.

E. coli were isolated from eight hospital (n = 721 isolates) and six municipal (n = 531 isolates) sewage samples, over 1 year in Gothenburg, Sweden. An inexpensive broth screening method was validated against disk diffusion and applied to determine resistance against 11 antibiotics in sewage isolates. Resistance data on E. coli isolated from clinical samples from corresponding local hospital and primary care patients were collected during the same year and compared with those of the sewage isolates by linear regression.

E. coli resistance rates derived from hospital sewage and hospital patients strongly correlated (r² = 0.95 for urine and 0.89 for blood samples), as did resistance rates in E. coli from municipal sewage and primary care urine samples (r² = 0.82). Resistance rates in hospital sewage isolates were close to those in hospital clinical isolates while resistance rates in municipal sewage isolates were about half of those measured in primary care isolates. Resistance rates in municipal sewage isolates were more stable between sampling occasions than those from hospital sewage.

Our findings provide support for development of a low-cost, sewage-based surveillance system for antibiotic resistance in E. coli, which could complement current monitoring systems and provide clinically relevant antibiotic resistance data for countries and regions where surveillance is lacking.

Escherichia coli ST131, a global, high-risk clone, comprises fluoroquinolone resistance (FQ-R) mutations and CTX-M extended-spectrum beta-lactamases associated with the fimH30-encoding clades, C1 and C2. Further carbapenem resistance development in ST131 is a public health concern.

This observational study aimed to probe the diversity of carbapenemase-producing E. coli (CP E. coli) ST131 across England.

ST131 isolates were identified using whole-genome sequencing (WGS) data generated for all non-duplicate CP E. coli from human samples submitted to the national reference laboratory from January 2014 to June 2016. Antimicrobial resistance (AMR) gene content and single nucleotide polymorphism (SNP) data were compared against a published ST131 phylogeny and analysed alongside patient metadata.

Thirty-nine genetically diverse ST131 CP E. coli, from eight of nine regions, represented 10% of CP E. coli isolates sequenced. Ten and eight isolates were from the FQ-susceptible (FQ-S) clades A and B, while eight and 15 isolates belonged to the FQ-R clades C1 or C2, respectively. Seven distinct carbapenemases were identified: KPC-2 (21 isolates, 6 regions) frequently occurred among clade C2 isolates (n = 10). OXA-48-producers (10 isolates, 3 regions) were often from clade A (n = 5). NDM-1 (n = 4), NDM-5 (n = 1), VIM-1 (n = 1), VIM-4 (n = 1) and OXA-181 (n = 1) were also identified. Clade C2 isolates encoded more AMR genes than those from clades A (p = 0.02), B (p = 9.6 x 10⁻³) or C1 (p = 0.03).

When compared with its global predominance among ESBL-E. coli, ST131 represented a fraction of the CP E. coli received, belonging to diverse clades and encoding diverse carbapenemases. The greater accumulation of resistance genes in clade C2 isolates highlights the need for ongoing monitoring of this high-risk lineage.

Q fever is a zoonosis, included in category B of particularly dangerous infectious agents and as such merits careful surveillance and regular updating of the information about its distribution.

This observational retrospective study aimed to provide an overview of Q fever incidence in Bulgaria in the period 2011 to 2017.

Aggregated surveillance data from Bulgaria’s mandatory surveillance system, laboratory data on individual samples received at the National Reference Laboratory Rickettsiae and Cell Cultures and outbreak reports sent by the regional health authorities to the National Centre of Infectious and Parasitic Diseases, were used in this analysis. Cases were described by year, region, age group and most commonly identified risk behaviours.

A total of 139 confirmed cases were reported in the study period (average annual incidence: 0.27 cases/100,000 inhabitants). No seasonality or trend in reported cases was observed. Cases were mostly sporadic, with two small outbreaks in 2017. Identified risk behaviours among cases were occupational exposure and consumption of milk and dairy products, although exposure data were incomplete. The male/female ratio was 1.4. The identification and resolution of the two rural outbreaks in 2017 with a total of 18 cases involved good practices: active case finding and collaboration between public health and veterinary authorities.

Between 2011 and 2017, Bulgaria retained low Q fever incidence, mostly sporadic cases and two small outbreaks. Occupational exposure and consumption of milk and dairy products were the most often reported likely exposures among cases. The outbreak investigations demonstrate the application of good control practices.