A nasopharynx swab is a diagnostic procedure involving the collection of a sample from the nasopharynx, the area behind the nose and above the throat, using a sterile swab. This procedure is crucial for identifying respiratory pathogens, including viruses like SARS-CoV-2 and bacteria such as Streptococcus pneumoniae, aiding in the diagnosis of infections like COVID-19 and pharyngitis. A key complication can be discomfort or bleeding at the site of swabbing.