Canada inks deal to produce Novavax COVID-19 vaccine “They just don’t go deep enough into the nasal cavity,” said Sowerby, who is an expert in the anatomy of the head, neck and inside of the nose.He says the results from the study caught him off guard.“As a surgeon who works inside the nose all the time, I was surprised to find that most of the instructions in Canada aren’t effective to reach the nasopharynx.”Sowerby says less than a quarter of public health instructions tell practitioners to insert the swab deep enough to reach the nasopharynx, which is the top of a person’s throat, behind their nose.Sowerby, along with Dr.