What are the differences between the Pre Delta, Delta and Omicron waves in children

Abstract

Introduction: Since March 2020, the country had experienced 5 epidemic waves: the Delta and Omicron variants were considered dominant respectively during the fourth and fifth waves. Objectives: To compare the clinical and evolutionary characteristics in children infected with Coronavirus-2 of Severe Acute Respiratory Syndrome before, during the emergence of Delta and when Omicron predominated. Methodology: Our study is retrospective descriptive and analytical, conducted at the Farhat Hached Sousse pediatric department from March 2, 2020 to February 28, 2022. Results: We included 125 patients, 26 in the pre-Delta period, 62 in the Delta period and 37 in the Omicron period. The median age was 6 months [2-44]. During the pre-Delta period, patients had more comorbidities: 50% of children. Otolaryngological and neurological signs were more common during the Omicron period than during the Delta period (p=0.004, p=0.015 respectively). The most dominant clinical form during the pre-Delta period was the critical form (38.5%) and during the Delta and Omicron period, children had a mild form in 75% and 59.4% of cases respectively. Conclusion: To our knowledge, our study is the first study comparing the waves of COVID-19 in children in Tunisia. Our results corroborate the scientific data in the literature that the pre-Delta period was the most critical period during the pandemic.