What Is a Sterile Swab?

Typically, a sterile swab has a collecting material, which may be a natural material or a synthetic material like polyester, at the tip of a stem or shaft. To use a swab, usually the user holds the stem and swipes the collecting material against a surface to collect a specimen. There are several varieties of swabs available because no single type is appropriate for all situations. Swabs are sterile to preserve the integrity of the samples and often have a resealable sterile container or bag to preserve that integrity during handling and transportation to the laboratory. Many different people use sterile swabs, including medical personnel, food producers, and crime scene investigators.

Sterile swab tips may vary in material, size, and shape, such as rounded or pointed. The swabs may be made of cotton fibers, polyester, or calcium alginate. Some companies manufacture the swab tips in different styles, including the flocking technique that uses blown fibers and an electrostatic environment. Typically, manufacturers wind the fibers around the tip of the stem. Wood, plastic, or metal are standard materials for the stem.

Some users, who need sterile collection products, collect samples from living beings, such as people, animals, or even plants. Other users collect samples from inert surfaces, including crime scenes, furnishings like food processing tables, and other areas. Many times the type of specimen required directs the type of sterile swab the user selects. For example, some Centers for Disease Control and Prevention (CDC) documents recommend using non-cotton swabs for checking for anthrax.

Sterile swab manufacturers offer dry and wet swabs. Typically, they pack sterile swabs in sterile packaging, such as paper, plastic, or plastic-coated paper sleeves. Many manufacturers offer packaging that is gamma-irradiated and hermetically sealed to protect the integrity of the swab. Some swabs are available in tubes and may contain a liquid, such as sterile water, sterile saline solution, or sodium chloride. A user should check with the laboratory that is going to process the specimen to learn which type of swab or solution to use.

For many applications, maintaining the integrity of the specimen is as important as using a sterile swab. Many companies have developed vials for this purpose. As with choosing the correct swab, a user should choose the proper specimen vessel. An example of a situation that requires special consideration is collecting blood-borne pathogens. To protect the people who handle the sample, some vials have breathable filters that allow the specimen to air dry without releasing contaminants into the air.

Collecting unadulterated specimens begins with sterile equipment, including the swab. Many places use sterile swabs to monitor the environment or work area, to control infections and their spread, and to monitor hygiene management programs. Some examples of these businesses include hospitals and health care facilities, food and pharmaceutical processing facilities, and animal care facilities such as veterinarian clinics and zoos.