Middle Ear Viral Load Considerations in the COVID-19 Era: A Systematic Review

Objective: To systematically review the available medical literature to investigate the viral load in the middle ear and mastoid cavity and the potential risk of exposure to airborne viruses during otologic surgery. Data Sources: PubMed, MEDLINE, and Cochrane databases. Study Selection: This review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Protocol. Data Extraction: Using the Boolean method and relevant search term combinations for terms "mastoid,""middle ear,""virus,""exposure""COVID-19""SARS-CoV-2."PubMed, MEDLINE, and Cochrane databases were queried. A total of 57 abstracts were identified and screened by two independent reviewers. Following inclusion and exclusion criteria, 18 studies were selected for the final analysis. Data Synthesis: Due to the heterogeneity of clinical data, a meta-analysis was not feasible. Results: Rhinovirus, followed by respiratory syncytial virus are reported to be the most prevalent viruses in MEF samples but formal statistical analysis is precluded by the heterogeneity of the studies. Drilling was identified to have the highest risk for aerosol generation and therefore viral exposure during otologic Surgery. Conclusions: The medical literature has consistently demonstrated the presence of nucleic acids of respiratory viruses involving the middle ear, including SARS-CoV2 in a recent postmortem study. Although no in vivo studies have been conducted, due to the likely risk of transmission, middle ear and mastoid procedures, particularly involving the use of a drill should be deferred, if possible, during the pandemic and enhanced personal protective equipment (PPE) used if surgery is necessary.