Possible healthcare-associated transmission as a cause of secondary infection and population structure of Staphylococcus aureus isolates from two wound treatment centres in Ghana

Abstract

We have previously shown that secondary infections of Buruli ulcer wounds were frequently caused by Staphylococcus aureus. To gain understanding into possible routes of secondary infection, we characterized S. aureus isolates from patient lesions and surrounding environments across two Ghanaian health centres. One hundred and one S. aureus isolates were isolated from wounds (n = 93, 92.1%) and the hospital environment (n = 8, 7.9%) and characterized by the spa gene, mecA and the Panton–Valentine leucocidin toxin followed by spa sequencing and whole genome sequencing of a subset of 49 isolates. Spa typing and sequencing of the spa gene from 91 isolates identified 29 different spa types with t355 (ST152), t186 (ST88), and t346 dominating. Although many distinct strains were isolated from both health centres, genotype clustering was identified within centres. In addition, we identified a cluster consisting of isolates from a healthcare worker, patients dressed that same day and forceps used for dressing, pointing to possible healthcare-associated transmission. These clusters were confirmed by phylogenomic analysis. Twenty-four (22.8%) isolates were identified as methicillin-resistant S. aureus and lukFS genes encoding Panton–Valentine leucocidin were identified in 67 (63.8%) of the isolates. Phenotype screening showed widespread resistance to tetracycline, erythromycin, rifampicin, amikacin and streptomycin. Genomics confirmed the widespread presence of antibiotic resistance genes to β-lactams, chloramphenicol, trimethoprim, quinolone, streptomycin and tetracycline. Our findings indicate that the healthcare environment probably contributes to the superinfection of Buruli ulcer wounds and calls for improved training in wound management and infection control techniques.

Molecular characterization of methicillin-resistant <i>Staphylococcus aureus</i> isolates from a hospital in Ghana

“…The frequency of tetK gene found in this study (19.0%) is close to that reported in another study in Ghana (16.3%) (28).…”

Challenges associated with the treatment of Buruli ulcer

“…All lesions were culture positive until 2 weeks but thereafter all were culture negative . Some follow‐up studies have indicated that healing delay may occur in up to two‐thirds of patients within 25 weeks from the start of SR treatment . Sarfo et al.…”

“…Reported practices, including not washing of wounds and surrounding intact skin, removal of old dressings without moistening exposing the wounds to trauma, wounds being cleaned by rubbing cotton wool soaked with dressing solutions on the wound instead of the application of moderate‐pressure irrigation, the choice of using different topical antiseptics instead of normal saline for wound cleaning, frequency of dressing changes not based on wound characteristics but on hospital policy, and the use of unsterilized materials for dressing wounds, have the potential of negatively impacting the healing of patients, increasing the risk of secondary infection of wounds, and ultimately delaying their reintegration into their families and society . The WHO guidelines for wound management exist and reports have shown that health workers have adequate knowledge and training on these guidelines; however, in some health facilities, adherence to the guidelines and delivery of proper wound care is hampered by the lack of adequate infrastructure, equipment, and wound dressing supplies . Providing appropriate facilities and tools to these health centers will empower them to be able to provide good care to patients.…”

Multi-Drug Resistant (MDR) Bacterial Isolates on Close Contact Surfaces and Health Care Workers in Intensive Care Units of a Tertiary Hospital in Bulawayo, Zimbabwe

“…Conventional PCR was used for the genetic detection of three major ESBL genes namely; blaTEM, blaSHV and blaCTX-M from the E. coli (11), Klebsiella pneumonia (13) and Pseudomonas aeruginosa (8) isolates obtained in the study. The primers used for each gene have been described in previous studies [33].…”

“…The increased interest in the use of copper surfaces in ICUs to reduce surface microbial load is testament of the potential role the environment may play in cross-transmission of HAIs [12]. Furthermore, numerous studies have employed molecular characterisation techniques including whole genome sequencing and Pulsed-field gel Electrophoresis (PFGE) to determine definitive genomic similarities between pathogens isolated from the hospital environment, HCWs hands as well as clinical specimens from admitted patients [7,8,13,14]. It has also been extensively reported that patients admitted into rooms previously occupied by a patient infected by MRSA, Clostridium difficile, Acinetobacter baumannii or vancomycinresistant enterococci (VRE) were more likely to acquire the infection of a previously admitted patient [15][16][17] .…”