SARS-CoV-2 Omicron Variant: Clinical Presentation and Occupational Implications in Young and Healthy IDF Soldiers

To this date, there is little known about the symptoms, their duration, and occupational implications of Coronavirus disease (COVID-19) in the military population. Decisions regarding implementing precaution measures are based on data deriving from the general population. Moreover, the Omicron variant seems to cause a disease with lesser severity than previous variants. We aimed to describe the clinical presentation and estimate the loss of workdays due to mild COVID-19 during an Omicron predominant wave among a young, healthy, and mostly vaccinated military population.

A cross-sectional, survey-based study among IDF soldiers who replied to an online questionnaire following recovery from COVID-19. Data included self-reported vaccination status, symptoms presentation and duration, and service-related sick days. Student's t-test and chi-square test of independence were used to compare differences in continuous and categorical variables, respectively. A binary logistic regression analysis was performed to estimate the odds ratio and 95% CIs for prolonged symptom duration (4 days and above) by participants' characteristics. The IDF medical corps institutional review board approved this study.

A total of 199 soldiers, with a mean age of 21.9 years, were included in the study. Upper respiratory tract symptoms, headache, and constitutional symptoms were found to be the most common among symptomatic soldiers. The median reported time for inability to continue the daily routine, including work, was 5 days [Interquartile range (IQR), 0-10]. Median duration of symptoms was 4 days (IQR, 0-10). In addition, women were found to have longer symptomatic disease (odds ratio = 2.34; 95% CI, 1.20-4.52).

Our findings demonstrate that even among a young and fully vaccinated population, COVID-19 caused by the Omicron variant may result in substantial medical leave from military service, compared to common cold or influenza virus infection. Our study sample was relatively small; however, the response rate was high and our results shed light on the yet-to-be fully characterized Omicron variant-related COVID-19. Despite the current common perception of COVID-19 as a self-limiting mild disease with low burden of symptoms, our findings show the potential occupational burden of infection with COVID-19 on military units and their readiness and could be considered when discussing public health restrictions and further steps taken to minimize outbreaks ramifications.