The Effect of Isotonic Saline Nasal Lavages in Improving Symptoms in SARS-CoV-2 Infection: A Case-Control Study

Washing Illness Away: A Systematic Review of the Impact of Nasal Irrigation and Spray on COVID-19

OBJECTIVE

Nasal irrigation is a common treatment for sinonasal disorders; however, it is unknown if it can reduce SARS-CoV-2 nasopharyngeal viral load (NVL). This systematic review investigated the efficacy of nasal irrigation with saline, povidone iodine (PVP-I), and intranasal corticosteroids (INCS) at reducing SARS-CoV-2 NVL and transmissibility.

DATA SOURCES

Databases including Embase, MEDLINE, Web of Science, and ClinicalTrials.gov.

REVIEW METHODS

A systematic review was completed with pre-defined search criteria using keywords related to nasal irrigation and COVID-19 from 1946 through January 2024. This review followed PRISMA reporting guidelines and was registered on PROSPERO. Only in-vivo studies testing nasal irrigation with either saline, PVP-I, or INCS for reducing NVL were included.

RESULTS

Nine out of ten studies on saline-based solutions reported positive effects in reducing NVL, with benefits noted in earlier time to negative nasopharyngeal PCR and a greater decline in NVL during early study time points, compared with controls. Isotonic and hypertonic saline mediums were found to be effective with three studies demonstrating enhanced efficacy with additives. Four out of seven studies on PVP-I showed a positive effect on reducing NVL, but results were heterogenous. Four studies demonstrated reduction of transmission with saline or PVP-I. No studies were found on INCS.

CONCLUSION

Saline nasal irrigation showed the best efficacy in reducing SARS-CoV-2 NVL. Additives to saline may have a clinical benefit, but further studies are needed to elucidate their isolated impacts on NVL. Data on PVP-I is inconclusive and further studies are warranted to determine the ideal concentration for irrigation. Laryngoscope, 135:517-528, 2025.

Seawater nasal wash to reduce symptom duration and viral load in COVID-19 and upper respiratory tract infections: a randomized controlled multicenter trial

PURPOSE

The objective was to assess the efficacy of seawater nasal wash on symptom duration, intranasal viral load, household transmission in COVID-19 and URTIs.

METHODS

This prospective, randomized, controlled, multicentric, parallel study included 355 mild/moderate COVID-19 and URTI adults with rhinologic symptoms ≤ 48h. Active group performed 4-daily nasal washes with undiluted isotonic seawater versus control group (without nasal wash). Symptoms were self-assessed daily using the WURSS-21 questionnaire for 3 weeks. Viral load was measured by RT-PCR on nasopharyngeal swabs collected on Day 0, Day 5, Day 14 and Day 21. Digital droplet PCR was additionally performed for SARS-CoV-2.

RESULTS

Overall COVID-19 subjects recovered earlier the ability to accomplish daily activities in the active group (- 1.6 day, p = 0.0487) with earlier improvement of taste (- 2 days, p = 0.0404). COVID-19 subjects with severe nasal symptoms at D0 showed the earliest resolution of anosmia (- 5.2 days, p = 0.0281), post-nasal drip (- 4.1 days, p = 0.0102), face pain/heaviness (- 4.5 days, p = 0.0078), headache (- 3.1 days, p = 0.0195), sore throat (- 3.3 days, p = 0.0319), dyspnea (- 3.1 days, p = 0.0195), chest congestion (- 2.8 days, p = 0.0386) and loss of appetite (- 4.5 days, p = 0.0186) with nasal wash. In URTIs subjects, an earlier resolution of rhinorrhea (- 3.5 days, p = 0.0370), post-nasal drip (- 3.7 days, p = 0.0378), and overall sickness (- 4.3 days, p = 0.0248) was reported with nasal wash. Evolution towards more severe COVID-19 was lower in active vs control, with earlier viral load reduction in youngest subjects (≥ 1.5log10 copies/10000 cells at Day 5: 88.9% vs 62.5%, p = 0.0456). In the active group, a lower percentage of SARS-CoV-2 positive household contacts (0-10.7%) was reported vs controls (3.2-16.1%) among subjects with Delta variant (p = 0.0413).

CONCLUSION

This trial showed the efficacy and safety of seawater nasal wash in COVID-19 and URTIs.

TRIAL REGISTRATION

Trial registry ClinicalTrials.gov: NCT04916639. Registration date: 04.06.2021.

Efficacy of physiological seawater nasal irrigation for the treatment of children with SARS-CoV-2 Omicron BA.2 variant infection: a randomized controlled trial

BACKGROUND

Saline nasal irrigation is an effective therapy for relieving common cold symptoms. This study aimed to investigate and explore the efficacy of physiological seawater nasal irrigation (PSNI) on children with mild and asymptomatic infection with Omicron.

METHODS

This randomized controlled trial was conducted in Shanghai, China, and 403 children with mild and asymptomatic infection with Omicron were included. These children were allocated into the PSNI group and the control group. The primary outcome was the duration of viral shedding (DVS), and the secondary outcome was the change in clinical symptoms.

RESULTS

The median age of all participants was 5.59 (6.26) years old. The DVS was significantly shorter in the PSNI group [2.40 (1.13)] than in the control group [3.09 (2.14)] (P = 0.014). The multivariable Cox regression model also showed that patients in the PSNI group had an increased probability of shorter DVS compared with patients in the control group [hazard ratio (HR), 1.27; 95% confidence interval (CI), 1.04-1.55; P = 0.017]. Subgroup analysis suggested that the DVS of patients without full vaccination was significantly reduced in the PSNI group. The proportions of runny nose and stuffy nose were apparently reduced in the first three days in the PSNI group or the control group, but there was no evidence showing that PSNI contributes to the benefit compared with the control group.

CONCLUSION

PSNI can reduce the DVS of patients with mild and asymptomatic infection with SARS-CoV-2 Omicron BA.2 variant.

Mechanism and treatment of olfactory dysfunction caused by coronavirus disease 2019

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the start of the pandemic, olfactory dysfunction (OD) has been reported as a common symptom of COVID-19. In some asymptomatic carriers, OD is often the first and even the only symptom. At the same time, persistent OD is also a long-term sequela seen after COVID-19 that can have a serious impact on the quality of life of patients. However, the pathogenesis of post-COVID-19 OD is still unclear, and there is no specific treatment for its patients. The aim of this paper was to review the research on OD caused by SARS-CoV-2 infection and to summarize the mechanism of action, the pathogenesis, and current treatments.

Saline nasal irrigation and gargling in COVID-19: a multidisciplinary review of effects on viral load, mucosal dynamics, and patient outcomes

With unrelenting SARS-CoV-2 variants, additional COVID-19 mitigation strategies are needed. Oral and nasal saline irrigation (SI) is a traditional approach for respiratory infections/diseases. As a multidisciplinary network with expertise/experience with saline, we conducted a narrative review to examine mechanisms of action and clinical outcomes associated with nasal SI, gargling, spray, or nebulization in COVID-19. SI was found to reduce SARS-CoV-2 nasopharyngeal loads and hasten viral clearance. Other mechanisms may involve inhibition of viral replication, bioaerosol reduction, improved mucociliary clearance, modulation of ENaC, and neutrophil responses. Prophylaxis was documented adjunctive to personal protective equipment. COVID-19 patients experienced significant symptom relief, while overall data suggest lower hospitalization risk. We found no harm and hence recommend SI use, as safe, inexpensive, and easy-to-use hygiene measure, complementary to hand washing or mask-wearing. In view of mainly small studies, large well-controlled or surveillance studies can help to further validate the outcomes and to implement its use.