In patients with upper respiratory infections, nasal irrigation with saline and providine-iodine rinses may provide efficacy in reducing viral titres, and nasal rinses generally appear to be beneficial in reducing nasal symptoms, although the effect of such rinses on COVID-19 infection is uncertain. These are among systematic review findings presented at the American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) 2022 Annual Meeting and OTO Experience, held in Philadelphia, Pennsylvania, September 10 to 14, 2022.
Researchers aimed to determine if the regular use of nasal rinses reduce viral load and transmissibility in patients with COVID-19 and other respiratory tract infections.
The researchers completed a systematic review in April 2022, searching for studies related to nasal irrigation, viral illnesses, and types of nasal rinse (including saline, corticosteroid, and providine-iodine) in ClinicalTrials.gov, Cochrane, Web of Science, Embase, and MEDLINE databases. From 1200 studies identified, 65 received full review, and 12 studies were ultimately used by researchers, who extracted data on type of nasal rinse used, viruses studied, viral load and transmission, and the effect of rinses on symptoms.
Among the 12 studies analyzed, 8 examined COVID-19. Ten of the studies were randomized controlled trials (RCTs), 6 using saline, 3 using providine, and 1 using an intranasal corticosteroid.
Among the 10 RCTs, 8 demonstrated that upper respiratory tract symptoms were reduced with nasal irrigation; 3 revealed a reduction in viral load; 4 reported specifically on viral load reduction in the nasopharynx; and 4 reported on side effects, the most common of which was mild nasal irritation. Only a single study reported data on transmission.
Researchers concluded that “While nasal rinses appear to be beneficial in reducing nasal symptoms of an upper respiratory tract infection, a larger scale study is needed to identify if these rinses impact the viral load, illness severity, and transmissibility in patients with COVID-19.” They further noted that nasal irrigation is well tolerated among patients with viral upper respiratory tract infections and has minimal risk. Moreover, there are conflicting results regarding the treatment and prevention of viral infections with nasal rinses; however, the data indicate that saline and providine-iodine rinses may offer some efficacy in reducing viral titres.
Gandhi K, Paczkowski F, Sowerby L. Nasal irrigation to prevent and treat viral upper respiratory tract infections during the COVID-19 pandemic. Otolaryngol Head Neck Surg. 2022;167(1 suppl):P285.