It is well known that mixing a half teaspoon each of salt and baking soda in a cup of boiled water and then putting it into a sinus rinse bottle can have a vital public health impact. The mixture provides extra hydration to the sinuses and enhances their functioning, stated Dr. Amy Baxter, corresponding author of the study from Augusta University, US. A recent study published in the journal Ear, Nose & Throat revealed that using nasal saline can reduce the risk of hospitalization and no fatality by 8.5 times in comparison to controls. According to the findings of the study, less than 1.3% of the 79 subjects enrolled in the study tested positive for COVID-19 between September 24 and December 21, 2020.

Among the participants, only one participant from the treatment group was admitted to the hospital, and another went to the emergency room but was not admitted. On the other hand, 9.47% of patients in the control group were hospitalized, while another 1.5% of the participants died. Dr. Baxter explained that the SARS-CoV-2 virus is known to attach to the ACE2 receptor, which is abundantly present throughout the body, especially in the nasal cavity, mouth, and lungs. She added that saline inhibited the virus′ ability to break itself into two parts, called furin cleavage, thereby increasing its adherence to an ACE2 receptor.

In the study, participants self-administered nasal irrigation using either antiseptic povidone-iodine or baking soda, mixed with water that had the same salt concentration normally found in the body. The study results showed that 23 out of the 29 participants who consistently irrigated twice daily had zero or one symptom at the end of two weeks in comparison to 14 of the 33 who were less diligent. But people who completed nasal irrigation twice daily reported quicker resolution of symptoms regardless of which of two common antiseptics they were adding to the saline water. 

(Source: https://www.thehindu.com/sci-tech/health/twice-daily-nasal-saline-flushing-may-reduce-covid-19-severity-study/article65885775.ece )