When Sampling Nasopharyngeal Swab is used for collection, the subject should tilt his head back. Sampling Nasopharyngeal Swab is not along the direction of nostrils, but perpendicular to the face and enters from the common nasal meae. Sampling Nasopharyngeal Swab should be pressed down as far as possible, close to the lower wall of the nasal cavity. After entering the nasopharynx, when there is an obvious "wall feeling", it should be gently rotated around and taken out vertically.
During collection, if there is resistance or when the tested person feels obvious pain, do not enter violently, Sampling Nasopharyngeal Swab slightly back. Meanwhile, adjust the Angle slightly in the sagittal plane before attempting to enter.
When Sampling Nasopharyngeal Swab collection is used, the operator can stand at the side and rear of the tested person without looking directly into the mouth, and there is basically no pharyngeal reflex, and the tolerance is good, and the exposure risk is relatively low. A sneeze reflex may occur in individual subjects after sampling and should be immediately covered with an elbow or tissue. A small number of subjects may have a little nosebleed after sampling, which can generally be stopped on its own. If necessary, a cotton swab with epinephrine can be used to slightly shrink the bleeding site. When Sampling Nasopharyngeal Swab is used for collection, it can stay in the nasopharynx for a longer time in order to obtain a more sufficient amount of samples.
Studies have shown that the positive rate of nasal swabs is higher than that of pharyngeal swabs, that is, the sampling efficiency of nasal swabs sensitive to viral nucleic acid detection is higher than that of pharyngeal swabs. Nasal swabs for viral nucleic acid testing should be given priority in clinical practice. This reduces missed diagnoses and reduces the potential exposure of health care workers to the virus.