A swab culture is a sample of bodily fluid taken for testing, using a sterile swab that appears similar to the common cotton swab found in many bathrooms. A medical swab is larger and may or may not be cotton. Once the sample is taken, the swab is generally placed into a sterile container and sent to a lab where the actual culture is performed. This is done by smearing the swab over a plate or slide and allowing the bacteria and other organisms to incubate and grow.
The sample is then viewed to determine which if any abnormalities are present. Different types of medicine may be applied to see which is the most effective, so the doctor or other healthcare provider can prescribe the best medicine. This is referred to as sensitivity testing. A swab culture can be used to test for many different types of health issues.
One common type is a throat swab culture used to test for strep throat. Samples are collected from the back of the throat and tonsil area and may be grown for several days before lab results are available. There is also an immediate test, which utilizes a coated strip with the swab. Antibodies on the strip, when combined with the body fluid on the swab, will create a reaction if there is strep. These quick tests don’t tend to be as reliable as a full swab culture performed by a lab.
Other types of swab cultures can be used in a similar manner to remove fluids from other areas of the body to test for disease or to identify DNA. Testing for health issues can include everything from testing for a simple urinary infection to testing for life threatening illnesses. Paternity testing kits are now available for home use, but there are other types of DNA testing, for purposes ranging from finding long-lost relatives to solving crimes.
A urethra swab culture for men or a cervical or vaginal swab culture for women may be used to test for particular types of sexually transmitted diseases. In some cases, a less intrusive, more superficial swab culture can be taken such as where sores or lesions are present. With wounds, including burns, a quantitative culture may be used to test for infection. A sputum swab, one that is used to collect a sample from what most people refer to as “phlegm,” can be used to test for tuberculosis.