Comparison of radiographic and CT appearances of covid-19 pneumonia and influenza pneumonia in a sub-Saharan Africa population

Document Type



Imaging and Diagnostic Radiology (East Africa); Pathology (East Africa); Internal Medicine (East Africa); Brain and Mind Institute


Background: The novel coronavirus (COVID-19) has infected over 600 million people worldwide with over 6 million deaths as of September 2022. Differentiation of the imaging appearance of COVID-19 pneumonia and the endemic seasonal influenza pneumonia is important as it may provide direction on patient care.

Objectives: The aim of this study was to evaluate differences in radiographic and computed tomography (CT) appearances of COVID-19 pneumonia and influenza pneumonia in a sub-Saharan Africa population.

Methods: This was a cross sectional descriptive study comparing patterns of pneumonia on radiographs and CT examinations of patients with COVID-19 pneumonia and influenza pneumonia. The comparisons included the predominant radiographic pattern of pneumonia and extent of pneumonia. The radiographic severity of disease was classified as mild, moderate or severe based on extent of lung involvement.

Results: A total of 99 examinations were reviewed, 52 chest x-rays and 47 CT chest examinations. Ground glass opacification had the highest sensitivity (89.5%) and negative predictive value (72.7%) in identification of COVID-19 pneumonia while reticulonodular opacities had the highest sensitivity (53.3%) and negative predictive value (68.2%) for identification of influenza pneumonia. The majority (90.9%) of Influenza pneumonia cases had lower CORADS scores of 2 and 3.

Conclusion: The presence of reticulonodular opacities can help differentiate influenza pneumonia from COVID-19 pneumonia. Radiographic differentiation of influenza pneumonia from COVID-19 pneumonia can assist in early triage and management of patients suspected to have either of these two pneumonias which can have similar clinical presentation but often variable severity and outcome.

Publication (Name of Journal)

East African Medical Journal