Comparison of the Copan ESwab™ System with Traditional Charcoal Swab in Stuarts Transport Medium


To compare the traditional system with charcoal swab in Stuarts medium with ESwab™ in Amies transport medium in a clinical setting in order to optimize the results of swab cultures from complicated wounds.


The Copan ESwab™ is a new nylon-flocked swab designed to optimize specimen collection and to minimize entrapment of the specimen in combination with liquid Amies transport medium, Fig 1. The ESwab™ has met the CLSI criteria for maintenance of viability of aerobic bacteria stored in both room and refrigerated temperature and anaerobic bacteria stored at refrigerated temperature.


One hundred and sixty hospitalized patients and outpatients at The Copenhagen Wound Healing Center, Bispebjerg Hospital were included.

On clinical indication, each patient had swabs taken from leg or foot wounds with both a charcoal swab and an ESwab™, from exactly the same part of the wound, Fig 2. The two swabs were placed in Stuarts medium and Amies medium, respectively and immediately transported at ambient temperature to the Department of Clinical Microbiology and cultured for aerobic and anaerobic bacteria.

Charcoal swabs in Stuarts medium were processed using standard routine procedures. From the ESwab™/Amies medium all plates were inoculated with 30 microliter/plate in order to detect at least 103 CFU/mL. The plates were incubated in aerobic and anaerobic atmosphere and read after 24h and 48h, respectively.