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

Gunadi,; Hakim, M. S.; Wibawa, H.; Marcellus,; Setiawaty, V.; Slamet,; Trisnawati, I.; Supriyati, E.; Khair, R. E.; Iskandar, K.; Afiahayati,; Siswanto,; Irene,; Anggorowati, N.; Daniwijaya, E. W.; Nugrahaningsih, D. A. A.; Puspadewi, Y.; Puspitarani, D. A.; Tania, I.; Vujira, K. A.; Ardlyamustaqim, M. B.; Gabriela, G. C.; Eryvinka, L. S.; Nirmala, B. C.; Geometri, E. T.; Darutama, A. A.; Kuswandani, A. A.; Lestari,; Irianingsih, S. H.; Khoiriyah, S.; Lestari, I.; Ananda, N. R.; Arguni, E.; Nuryastuti, T.; Wibawa, T.; group, Yogyakarta-Central Java COVID-19 study

Background: SARS-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. Methods: We 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. Results: The 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. Conclusions: We 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.