Influenza viruses and SARS-CoV-2 in adult: 'Similarities and differences'

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), causing a global pandemic starting from December 2019, showed a course that resulted in serious mortality in the world. In order to understand SARSCoV-2 better, here we aimed to compare the similar and different characteristics of Influenza viruses occurring in the same season with SARS-CoV-2.

A total of 144 patients (31 patients with COVID-19, 62 patients with H1N1 influenza, and 51 patients with influenza B) were included in the study. Demographic findings, chronic diseases, laboratory values, chest x-ray, and chest CT findings of the patients were evaluated retrospectively.

Median age of the COVID-19 patients and rate of male patients were higher than other patient groups (55 years; p< 0.001) (61% male; p< 0.001). The most common chronic medical conditions were hypertension and diabetes. Platelet numbers and alanine aminotransferase values were significantly higher in COVID-19 patients. Radiologically, bilateral (74.2%) and nonspecific distribution (58.1%), ground-glass opacities with consolidation (51.6%), patchy image (25.8%), ground-glass opacities with interstitial changes (22.6%) and halo sign (22.6%) were quite evident than other groups in COVID-19 patients (p< 0.05).

We suggest that due to the higher PLT values observed in COVID-19 patients, initiation of anticoagulant therapy should be considered in the early stage and routine follow-up with d-dimer and fibrinogen should be applied for suspected patients. Moreover, attention should be paid in terms of possible liver toxicity of the drugs to be used in treatment due the higher ALT values observed in COVID-19 patients. Since we did not detect SARS-CoV-2 and influenza viruses concurrently in the same patient, it may be helpful to focus on only one virus in a patient with symptoms, and radiographic differences can be used to differentiate COVID-19 from influenza.