ABSTRACT
To estimate the prevalence of West Nile virus (WNV) immunoglobulin G (IgG) antibodies in residents of northern Greece before the large outbreak of 2010, stored serum samples collected during 2003-2004 from 626 apparently healthy residents of northern Greece were tested. A seroprevalence of 0.62% was detected, with no statistically significant differences among the various prefectures, gender, and age groups, suggesting that the lineage 2 WNV strain that caused the outbreaks for 3 consecutive years was introduced recently. Data from the present study can be used as a threshold in future comparisons with respective data after the outbreaks to estimate and assess the public health impact, as well as for WNV evolutionary studies.
Subject(s)
Antibodies, Viral/blood , Disease Outbreaks , Immunoglobulin G/blood , West Nile Fever/epidemiology , West Nile virus/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Greece/epidemiology , Humans , Infant , Male , Middle Aged , Public Health , Retrospective Studies , Seroepidemiologic Studies , West Nile Fever/virology , West Nile virus/isolation & purification , Young AdultABSTRACT
OBJECTIVES: To characterize UK clinical isolates of Enterobacteriaceae producing OXA-48-like carbapenemases and to compare their resistance plasmids. METHODS: Twenty-six enterobacteria producing OXA-48-like enzymes were studied. These were from 22 diverse hospitals in the UK. Isolates of Escherichia coli and Klebsiella pneumoniae were assigned to clonal lineages by multilocus sequence typing. Carbapenemase genes and their genetic environments were characterized by PCR and sequencing. Resistance plasmids were transferred by transformation or conjugation and compared by restriction analysis and PCR for genes encoding critical plasmid functions. RESULTS: Thirteen isolates of K. pneumoniae, 10 E. coli and 2 Enterobacter cloacae harboured a classical bla(OXA-48) gene; the K. pneumoniae isolates belonged to 11 sequence types (STs) and the E. coli to 7 STs, including ST131 and ST38. The bla(OXA-48) genes were located within either Tn1999 or Tn1999.2 transposons on related ≈ 50 kb or ≈ 62 kb plasmids, which lacked other resistance genes or, in one isolate, on an ≈ 140 kb plasmid that also encoded OXA-9 and CTX-M group-9 ß-lactamases. One India-linked K. pneumoniae isolate had a bla(OXA-181) gene in association with an ISEcp1 insertion sequence on a 7 kb plasmid. CONCLUSIONS: Horizontal transfer of related plasmids has facilitated the spread of OXA-48 carbapenemase into multiple strains of several Enterobacteriaceae species. The clonal diversity of the producers suggests repeated introduction into the UK. Low carbapenem MICs for some producers complicates detection and creates a risk for unrecognized spread.
