Throat and nasal swabs are one of the most extensively used methods for detecting the presence of coronavirus in a person. Both fast antigen and RT-PCR tests, which are now in widespread use, involve healthcare practitioners inserting a swab and gently pushing the inside of a person’s nostrils to collect as much nasal discharge as possible for testing.
But why do certain healthcare staff go the extra mile?
Our nasal cavity is far bigger than our nose, reaching into the skull and flowing down the back of our throat.
Coronavirus particles inhaled can adhere to various soft tissues in the nasal cavity or throat. The goldmine is the nasopharynx, which is located in the upper portion of the throat behind the nose and is used by healthcare practitioners to determine whether or not a person has caught the virus.
The nasopharynx is located in the upper respiratory system, and the Centers for Disease Control and Prevention (CDC) has established recommendations for sampling mucosa from there. It specifies that only synthetic fiber swabs with thin plastic or wire shafts, rather than calcium alginate swabs or swabs with wooden shafts, should be used to capture the specimen.
However, getting to the nasopharynx might be unpleasant since the testing swab must pass through four inches of delicate, sensitive tissues. And, according to the standards, must remain for 15 seconds for sample collection.
The virus is less likely to be detected in a sample taken from the middle of shallow portions of the nose. It is only beneficial if a person possesses a viral load in the nose.
Covid-19 test types
According to Dr. Hanan Balkhy, Assistant Director-General for Antimicrobial Resistance at the World Health Organization (WHO), there are three types of testing.
The first is a NAAT test, which determines whether the real Covid viral genetic material exists. A nasal pharyngeal swab or pharyngeal swab would be obtained for PCR testing. Then, she said, they seek the virus’s genetic material.
The second form of testing is attempting to identify one of the viral shells or envelope’s outer protesting. This is known as antigen testing. The third type is to identify whether antibodies have evolved within the human body, she noted.