Final answer:
A rectal swab should be gently inserted only 1 to 2 inches (2.5 to 5 cm) into the rectum for sample collection, ensuring sterility and patient comfort.
Step-by-step explanation:
When collecting a sample using a rectal swab, it is important to be gentle and follow proper guidelines to avoid discomfort or injury. The rectum is the final 20.3 cm (8 in) of the alimentary canal, extending anterior to the sacrum and coccyx. Based on medical standards and anatomical considerations, the swab should not be inserted more than 1 to 2 inches (approximately 2.5 to 5 cm) into the rectum to ensure that it is within the correct sampling area while minimizing discomfort.
Make sure that you are using a sterile swab and that the procedure is performed in a sanitary environment to prevent contamination or infection. The collected sample can then be used for microbiological analysis, similar to the process mentioned for an oral mucosa sample, but the specifics of the handling and culturing will be different and must adhere to rectal sampling protocols.