Patients with respiratory viral infections are likely to develop co-infections, which increase the severity of their disease. Streptococcus pneumonia infection was found to be the cause of death in the majority of cases during the 1918 influenza outbreak.¹ COVID-19 is a viral disease caused by the SARS-CoV-2. While the large majority of infections are mild in nature, around 20% of patients develop severe disease with complications such as pneumonia, acute respiratory distress syndrome (ARDS) due to bacterial superinfections, ² as evident by the high neutrophil count and a significantly lower lymphocyte count in these cases. ³

Underlying obesity, diabetes, heart disease and hypertension predispose to severe COVID-19 disease. Poor oral health increases the risk of developing these conditions suggesting a link between poor oral health and severity of COVID-19 complications.⁴ Aspiration of oral secretions and their, alteration of the respiratory epithelium by periodontal-associated cytokines, and oral mucosal surfaces which promote adhesion of respiratory pathogens have been suggested as possible mechanisms via which oral pathogens can cause and worsen lung infections. ^5,6 Good oral hygiene prevents spread of oral bacteria to other parts of the body, including the lungs.⁶ Interventions that improve oral hygiene have been shown to reduce risk of pneumonia. ⁷ 

Gargling is a common oral hygiene practice. Antiseptic mouthwashes/gargles reduce oral biofilm formation thereby decreasing the oral microbial load and in turn preventing development of complications.

Gargling with an oral antiseptic such as povidone-iodine (PVP-I) improves oral hygiene. The advantages of PVP‐I are its universal spectrum of antimicrobial activity (covering Gram-positive and Gram-negative bacteria, viruses, fungi, protozoa, and bacterial spores), faster onset of action, more persistent effect and low potential for resistance. ^4,8,9 It is also safe.¹⁰ PVP-I has rapid virucidal activity against SARS-CoV-2^11,12 and significantly reduces viral load in the oral cavity and the oropharynx. ¹³

In an article published in the British Dental Journal, Sampson et al have written, “Good oral hygiene has been recognized as a means to prevent airway infections in patients, especially in those over the age of 70”…. “oral hygiene be maintained, if not improved, during a SARS-CoV-2 infection in order to reduce the bacterial load in the mouth and the potential risk of bacterial superinfection.” ²

Masking, hand hygiene and physical distancing are recommended as protective measures. To these can be added, PVP-I gargles, which not only decrease replication of SARS-CoV-2 in the throat and prevent spread of infection, they also improve oral hygiene and prevent complications such as pneumonia in patients with COVID-19, thereby reducing morbidity and mortality. This is particularly important for patients who have underlying disease conditions.

References

1. Cox M J, et al. Co-infections: potentially lethal and unexplored in COVID-19. Lancet 2020; DOI: 10.1016/S2666-5247(20)30009-4
2. Sampson V, et al. Could there be a link between oral hygiene and the severity of SARS-CoV-2 infections? Br Dent J. 2020;228(12):971-5.
3. Zheng M, et al. Functional exhaustion of antiviral lymphocytes in COVID-19 patients. Cell Mol Immunol 2020;17:533-5.
4. Botros N, et al. Is there an association between oral health and severity of COVID-19 complications? Biomed J. 2020 Aug;43(4):325-7.
5. Yoneyama T, et al. Oral care reduces pneumonia in older patients in nursing homes. J Am Geriatr Soc. 2002;50(3):430-3.
6. Patel J, et al. The role of oral bacteria in COVID-19. Lancet Microbe. 2020;1(3):e105.
7. Manger D, et al. Evidence summary: the relationship between oral health and pulmonary disease. Br Dent J. 2017;222:527-33.
8. Lachapelle JM, et al. Antiseptics in the era of bacterial resistance: a focus on povidone iodine. Clin Pract 2013;10:579–92.
9. Kanagalingam J, et al. Practical use of povidone-iodine antiseptic in the maintenance of oral health and in the prevention and treatment of common oropharyngeal infections. Int J Clin Pract. 2015;69(11):1247-56.
10. Vergara-Buenaventura A, et al. Use of mouthwashes against COVID-19 in dentistry. Br J Oral Maxillofac Surg. 2020;58(8):924-7.
11. Anderson DE, et al. Povidone-iodine demonstrates rapid in vitro virucidal activity against SARS-CoV-2, the virus causing COVID-19 disease. Infect Dis Ther. 2020:1–7.
12. Hassandarvish P, et al. Povidone iodine gargle and mouthwash. Br Dent J. 2020;228(12):900.
13. Eggers M. infectious disease management and control with povidone iodine. Infect Dis Ther. 2019;8(4):581-593.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA