To the average patient, a flu test may seem simple. Stick a long swab up someone's nose and test the swab for the virus. Easy, right?
We know differently.
Diagnosing the flu is a process, and like any other scientific process, it requires specific tools, the first of which is a specimen collection swab. But which type of swab is the best tool for the job?
The American Society for Microbiology (ASM) recommends flocked swabs as the preferred specimen collection device for flu testing. In fact, flocked swabs have been hailed by the microbiology and diagnostic communities for their ability to absorb and elute more specimen than traditional spun fiber or foam swabs.
At the microscopic level, the synthetic tip of a flocked swab is brush-like, and has more surface area than cotton and is, therefore, able to collect and elute more material. The brush-like tip of the flocked swab also provides for better specimen collection and release during testing.
Many physicians also find specimen collection with flocked swabs easier and less likely to cause patient discomfort than with other swab types.
Looking for more? Here's a step-by-step guide on how to swab for the flu with flocked swabs.
Like the cotton swabs, rayon tipped swabs are made from spun fiber. This fiber is synthetic, low cost, soft and absorbent, and can be used for many applications where cotton would not be suitable, such as for diagnostic specimen collection.
While not quite as efficient as the flocked swab, the rayon swab fiber is produced from weed through a denaturing process that eliminates any natural materials that may damage the specimen or interfere with specimen processing.
Polyester tipped swabs are the next step-up when it comes to specimen collection. They have excellent collection properties and, while somewhat more costly than cotton or rayon, boast superior release properties. Polyester fiber has been tested and validated for use in specimen collection in microbiology, rapid diagnostic tests and PCR analysis.
Medical grade polyurethane foam is also used as a tip material for diagnostics. The advantage of using a foam-tipped swab is that this tip type come in various tip shapes, sizes and porosities, so your intended use dictates which foam-tipped swabs will work best.
All of these swab options are offered in sterile individually wrapped peel pouches or in dry transport tubes.
The traditional spun cotton-tipped swab is the most familiar single-use device in the medical industry. It is absorbent, soft, low cost, safe and incredibly useful in many applications, but it is not recommended for specimen collection.
Why is that, you ask? Two reasons: Cotton fiber entraps the specimen, and the result is very poor release. And, the naturally occurring fatty acids inherent in this fiber interfere with the processes used in microbiology.
Interested in learning more about why flocked swabs are the superior tool for the job?