What’s New in the World of Swabs?

Every microbiologist knows that the best specimens for culture are fluids or tissue. However, we rarely get what we want. The majority of the specimens that microbiology laboratories receive are collected on swabs. Clinicians favor the swab as a collection and transport system because of its ease of use, low cost, and availability. What is the laboratory to do? We need to understand the various swab transport systems, encourage our clinical colleagues to give us the best specimens possible and when we are stuck with swabs, make them the best swab we can find for the specific job. The use of the swab to collect a specimen was first recorded in 1893. Since then various holding media, shafts, and tip material have been used in attempts to find the best swab transport system. For this review we will present the components of swabs and compare some commercial brands, including the newest commercially available swab, the flocked swab. Swab transport and collection systems are composed of two parts: the swab and the medium in the bottom of the tube. The swab is composed of the tip, which is made of some material designed to collect, hold, and release the organism onto or into a culture medium, and the shaft, which enables the tip to reach the desired sight for testing without contaminating the swab or the user. In the bottom of the tube is the medium designed to maintain viability of any collected organisms. The medium can be a gel or can be a medium-soaked polyurethane foam sponge.