Comparison of viral load among patients with or without COVID-19 pneumonia Delta variant

Abstract

This research aimed to compare viral load among patients with or without COVID-19 pneumonia Delta variant. This study is a retrospective descriptive study of 249 COVID-19 patients admitted to Chaiyaphum Hospital between October and December 2021. There were 166 COVID-19 patients without pneumonia and 83 COVID-19 patients with pneumonia. Chest radiographs were evaluated using the Brixia scoring system. Differences in continuous and categorical variables between the two groups were assessed using a Wilcoxon rank sum test and Chi-square test or Fisher exact test, respectively. The viral load Ct value was described by mean and standard deviation (SD) and used a two-sample independent t-test to compare between two groups. The determined risk factor associated with pneumonia in COVID patients was used logistics regression at a significant level of 0.05. The results show that the group of COVID-infected patients with pneumonia had a significantly lower viral load Ct value than the group of COVID-infected patients without pneumonia (mean ± SD; 19.1 ± 4.3 vs. 20.9 ± 6.0, P = 0.01), respectively. Ct value < 23 is associated with COVID-19 pneumonia Delta variant (sensitivity 85.5%, specificity 27.1%). Viral load results vary according to the CXR severity score. The risk factors associated with COVID-infected pneumonia were age ≥ 60 years [aOR:7.30 (95% CI: 3.57-14.94)], BMI ≥ 25 [aOR:1.90 (95% CI: 1.01-3.59)], hypertension [aOR:3.11 (95% CI: 1.22-7.97)] and Viral load Ct value < 23 [aOR:2.22 (95% CI: 1.02-4.83)]. Viral load is associated with pneumonia in COVID-19 patients with the Delta variant and correlates with the CXR severity score. There should be consideration for testing the viral load in COVID-infected patients with risk factors for the development of pneumonia for the purpose of planning treatment and subsequent follow-up with chest radiography.