COVID-19 予防だけでなく治療にも有効な鼻うがい






Rapid initiation of nasal saline irrigation to reduce severity in high-risk COVID+ outpatients
【SageJounals 2022年8月25日】



To determine whether initiating saline nasal irrigation after COVID-19 diagnosis reduces hospitalization and death in high-risk outpatients compared with observational controls, and if irrigant composition impacts severity.


Participants 55 and older were enrolled within 24 hours of a + PCR COVID-19 test between September 24 and December 21, 2020. Among 826 screened, 79 participants were enrolled and randomly assigned to add 2.5 mL povidone-iodine 10% or 2.5 mL sodium bicarbonate to 240 mL of isotonic nasal irrigation twice daily for 14 days. The primary outcome was hospitalization or death from COVID-19 within 28 days of enrollment by daily self-report confirmed with phone calls and hospital records, compared to the CDC Surveillance Dataset covering the same time. Secondary outcomes compared symptom resolution by irrigant additive.


Seventy-nine high-risk participants were enrolled (mean [SD] age, 64 [8] years; 36 [46%] women; 71% Non-Hispanic White), with mean BMI 30.3. Analyzed by intention-to-treat, by day 28, COVID-19 symptoms resulted in one ED visit and no hospitalizations in 42 irrigating with alkalinization, one hospitalization of 37 in the povidone-iodine group, (1.27%) and no deaths. Of nearly three million CDC cases, 9.47% were known to be hospitalized, with an additional 1.5% mortality in those without hospitalization data. Age, sex, and percentage with pre-existing conditions did not significantly differ by exact binomial test from the CDC dataset, while reported race and hospitalization rate did. The total risk of hospitalization or death (11%) was 8.57 times that of enrolled nasal irrigation participants (SE = 2.74; P = .006). Sixty-two participants completed daily surveys (78%), averaging 1.8 irrigations/day. Eleven reported irrigation-related complaints and four discontinued use. Symptom resolution was more likely for those reporting twice daily irrigation (X2 = 8.728, P = .0031) regardless of additive.


SARS-CoV-2+ participants initiating nasal irrigation were over 8 times less likely to be hospitalized than the national rate.


Pharmacologic and immunologic COVID-19 therapeutics seek to inhibit mechanical binding of the SARS-CoV-2 spike protein-receptor to the ACE2 receptor and spike segment furin cleavage necessary for cell entry. Sungnak et al. localized the necessary co-expression of ACE2 and protease TMPRSS2 primarily in the ciliated nasal epithelia, supporting the clinical correlation of nasal viral load and severity and suggesting a location for early intervention. The increased infectiousness resulting from physical changes with viral spike protein mutations support a mechanical opportunity to interrupt viral particle receptor binding and entry. The observation that saline can inhibit furin cleavage suggests a mechanical therapeutic option––nasal irrigation––may be particularly effective against this pathogen.
Nasal irrigation under pressure, or “nasal lavage,” has been demonstrated to safely reduce the duration and severity of both Coronaviridae and illnesses like flu with shorter incubation periods. Repeated irrigation should be most effective for pathogens with prolonged incubation, local non-hematogenous spread, and variolation where viral load impacts severity.
Given research supporting the virucidal activity of povidone-iodine against MERS and SARS-CoV-2 and the possible impact of alkalinization to reduce SARS-CoV-1 viral cell fusion and entry, patients were randomized to add alkalinization or povidone-iodine to pressurized nasal lavage. We hypothesized rapid initiation of nasal irrigation after testing positive would reduce the severity of COVID-19. Our primary outcome was COVID-19 hospitalization or death, with secondary outcomes of symptom duration, severity, and household spread. If clinically effective, irrigation could be an inexpensive option rapidly available worldwide.