Is the infection of the SARS-CoV-2 Delta variant associated with the outcomes of COVID-19 patients?

ABSTRACT

BackgroundSARS-CoV-2 Delta variant (B.1.617.2) has been responsible for the current increase in COVID-19 infectivity rate worldwide. We compared the impact of the Delta variant and non-Delta variant on the COVID-19 outcomes in patients from Yogyakarta and Central Java provinces, Indonesia. MethodsWe ascertained 161 patients, 69 with the Delta variant and 92 with the non-Delta variant. The Illumina MiSeq next-generation sequencer was used to perform the whole genome sequences of SARS-CoV-2. ResultsThe mean age of patients with Delta and the non-Delta variant was 27.3 {+/-} 20.0 and 43.0 {+/-} 20.9 (p=3x10-6). The patients with Delta variant consisted of 23 males and 46 females, while the patients with the non-Delta variant involved 56 males and 36 females (p=0.001). The Ct value of the Delta variant (18.4 {+/-} 2.9) was significantly lower than the non-Delta variant (19.5 {+/-} 3.8) (p=0.043). There was no significant difference in the hospitalization and mortality of patients with Delta and non-Delta variants (p=0.80 and 0.29, respectively). None of the prognostic factors was associated with the hospitalization, except diabetes with an OR of 3.6 (95% CI=1.02-12.5; p=0.036). Moreover, the patients with the following factors have been associated with higher mortality rate than patients without the factors age [≥]65 years, obesity, diabetes, hypertension, and cardiovascular disease with the OR of 11 (95% CI=3.4-36; p=8x10-5), 27 (95% CI=6.1-118; p=1x10-5), 15.6 (95% CI=5.3-46; p=6x10-7), 12 (95% CI=4-35.3; p=1.2x10-5), and 6.8 (95% CI=2.1-22.1; p=0.003), respectively. Multivariate analysis showed that age [≥]65 years, obesity, diabetes, and hypertension were the strong prognostic factors for the mortality of COVID-19 patients with the OR of 3.6 (95% CI=0.58-21.9; p=0.028), 16.6 (95% CI=2.5-107.1; p=0.003), 5.5 (95% CI=1.3-23.7; p=0.021), and 5.8 (95% CI=1.02-32.8; p=0.047), respectively. ConclusionsWe show that the patients infected by the SARS-CoV-2 Delta variant have a lower Ct value than the patients infected by the non-Delta variant, implying that the Delta variant has a higher viral load, which might cause a more transmissible virus among humans. However, the Delta variant does not affect the COVID-19 outcomes in our patients. Our study also confirms the older age and comorbidity increase the mortality rate of COVID-19 patients.