Dr. Prashant Ved (Emergency Medicine) needs a second opinion on this medical case.
Saliva As Protective Shield Against SARS-Cov-2
Hyposalivation as a potential risk factor for a SARS‐CoV‐2 infection was discussed in an article published in Oral Diseases. Human saliva is a very complex fluid and plays a crucial role in the prevention of viral infections and protection against them, since it contains a large number of proteins and peptides with antiviral effects. Previous studies have documented the antiviral effects of some of those proteins against other coronaviruses. In addition, such proteins have been reported to inhibit the replication of other coronaviruses. According to the authors, it is therefore reasonable to assume that the protective effect of these salivary proteins against SARS-CoV-2 might be similar.
Another previous study has suggested that hyposalivation could lead to acute respiratory infection, because the reduced saliva secretion may impair the oral and airway mucosal surface and may result in a decreased secretion of antimicrobial proteins and peptides. Thus, hyposalivation may expose patients to a higher risk of contracting SARS‐CoV‐2. However, the study authors acknowledge that further studies on this topic are needed to prove this hypothesis.
Is mucosal immunity more important?
Although several knowledge gaps about SARS-CoV-2 exist, it is clear that a vaccine is urgently needed to prevent infection and possible reinfection in the long term. A study published recemtly addressed the question of whether mucosal SARS-CoV-2 vaccines would be more effective than parenteral vaccines. Owing to their genetic similarity, the development of MERS-CoV and SARS-CoV-1 vaccines in recent years has provided important insights for the development of SARS-CoV-2 vaccines. In an experimental series of SARS-CoV-1/MERS-CoV vaccines, mucosal vaccination resulted in attractive protective correlates—even higher than with parenteral vaccines. Thus, the research of mucosal vaccine candidates should be encouraged for developing effective SARS-CoV-2 vaccines.