A rectal swab sample refers to a biological specimen collected from the rectum using a swab for diagnostic or research purposes. Rectal swabs are commonly used in medical settings to detect various infections, particularly those caused by bacteria, viruses, or parasites that can affect the gastrointestinal tract.

The process typically involves inserting a swab into the rectum and gently rotating it to collect a sample of cells or secretions. This sample is then sent to a laboratory for analysis, where it can be cultured, examined under a microscope, or subjected to molecular testing methods such as PCR (polymerase chain reaction) to identify the presence of pathogens or abnormalities.

Rectal swab samples may be collected for various reasons, including screening for sexually transmitted infections (STIs), investigating gastrointestinal symptoms, monitoring the effectiveness of treatment, or conducting research on the microbiome of the gut. The procedure is usually quick and relatively non-invasive, though it may cause some discomfort or embarrassment for the patient.