Local circulating clones of Staphylococcus aureus in Ecuador

Abstract

The spread of pandemic Staphylococcus aureus clones, mainly methicillin-resistant S. aureus (MRSA), must be kept under surveillance to assemble an accurate, local epidemiological analysis. In Ecuador, the prevalence of the USA300 Latin American variant clone (USA300-LV) is well known; however, there is little information about other circulating clones. The aim of this work was to identify the sequence types (ST) using a Multiple-Locus Variable number tandem repeat Analysis 14-locus genotyping approach. We analyzed 132 S. aureus strains that were recovered from 2005 to 2013 and isolated in several clinical settings in Quito, Ecuador. MRSA isolates composed 46.97% (62/132) of the study population. Within MRSA, 37 isolates were related to the USA300-LV clone (ST8-MRSA-IV, Panton-Valentine Leukocidin [PVL] +) and 10 were related to the Brazilian clone (ST239-MRSA-III, PVL-). Additionally, two isolates (ST5-MRSA-II, PVL-) were related to the New York/Japan clone. One isolate was related to the Pediatric clone (ST5-MRSA-IV, PVL-), one isolate (ST45-MRSA-II, PVL-) was related to the USA600 clone, and one (ST22-MRSA-IV, PVL-) was related to the epidemic UK-EMRSA-15 clone. Moreover, the most prevalent MSSA sequence types were ST8 (11 isolates), ST45 (8 isolates), ST30 (8 isolates), ST5 (7 isolates) and ST22 (6 isolates). Additionally, we found one isolate that was related to the livestock associated S. aureus clone ST398. We conclude that in addition to the high prevalence of clone LV-ST8-MRSA-IV, other epidemic clones are circulating in Quito, such as the Brazilian, Pediatric and New York/Japan clones. The USA600 and UK-EMRSA-15 clones, which were not previously described in Ecuador, were also found. Moreover, we found evidence of the presence of the livestock associated clone ST398 in a hospital environment.

Molecular Diversity of Staphylococcus aureus Colonizing the Upper Respiratory Tract of Residents and Staff in A Nursing Home

“…The MLVF of the 66 S. aureus strains isolated from 47 individuals resulted in 51 banding patterns: 36 unique banding patterns were represented by only one strain and 15 banding patterns consisted of two identical S. aureus strains each. In accordance with our results, a high genetic diversity of MSSA has been reported in other studies (Emaneini et al 2011;Karynski et al 2008;Zurita et al 2016 Note. S. aureus strains marked with the same number were retrieved from the anterior nares (N) and the throat (T) of one resident (R) or staff member (S) and had 100% genetic homology according to the MLVF analysis.…”

“…Staphylococcus aureus is an opportunistic human pathogen known for its increasing prevalence in both hospitals and the general community. An incremental rise in drug-resistance and high disease-causing capabilities has also been observed (Zhang et al 2015;Zurita et al 2016). The most common anatomical location for the commensal carriage of S. aureus is the anterior nares (Kluytmans et al 1997;Pollitt et al 2018), although recent epidemiological studies highlight the role of pharyngeal carriage in S. aureus transmission (Nilsson and Ripa 2006;Hamdan-Partida et al 2010).…”

“…S. aureus is also one of the most genetically diverse bacteria and the mechanisms by which the predominant strains are selected within each biological niche depends on the geographic location as well as the studied human host (Zurita et al 2016). MSSA strains are more prevalent than MRSA strains and have a higher genetic diversity, whereas MRSA outbreaks are usually caused by only a few different MRSA clones (Goering et al 2008).…”

Molecular Typing of ST239-MRSA-III From Diverse Geographic Locations and the Evolution of the SCCmec III Element During Its Intercontinental Spread

“…These isolates originated from hospitals in Ireland, Germany, Romania, Kuwait, Saudi Arabia, Russia, Pakistan, China/Hong Kong, Australia, Trinidad&Tobago, and Ecuador as well as some reference strains (see Supplemental Table 1 and below). Some of the isolates were a convenience sample from previous studies (Monecke et al, 2008a , 2011 , 2012b , c , 2014a , b , 2016 ; Albrecht et al, 2011 ; Boswihi et al, 2016 ; Senok et al, 2016 ; Zurita et al, 2016 ; Gostev et al, 2017 ; Jamil et al, 2017 ). Others came from ongoing routine diagnostics, outbreak investigations or typing tasks performed by the authors and have not been published previously.…”

“…In Eastern Australia and New Zealand it was a common cause of HCA infection, and it has been reported in association with large MRSA outbreaks (Coombs et al, 2004 ; Howden et al, 2010 ). In the western hemisphere, CC239-MRSA-III has been reported from the United States (Schaefler et al, 1981 ), Brazil (Vivoni et al, 2006 ), Paraguay (Mayor et al, 2007 ), Ecuador (Zurita et al, 2016 ), and Trinidad & Tobago where it recently was still the predominant MRSA strain (Akpaka et al, 2007 ; Monecke et al, 2012b , 2014b ).…”