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. 2024 Mar 28;14(4):358.
doi: 10.3390/jpm14040358.

Delta Variant in the COVID-19 Pandemic: A Comparative Study on Clinical Outcomes Based on Vaccination Status

Damiana-Maria Vulturar  1 , Liviu-Ștefan Moacă  1 , Maria Adriana Neag  2 , Andrei-Otto Mitre  3 , Teodora-Gabriela Alexescu  4 , Diana Gherman  5 , Iulia Făgărășan  1 , Ioana Maria Chețan  1 , Claudia Diana Gherman  6 , Oana-Elena Melinte  7 , Antigona Carmen Trofor  7 , Doina-Adina Todea  1
Affiliations

Delta Variant in the COVID-19 Pandemic: A Comparative Study on Clinical Outcomes Based on Vaccination Status

Damiana-Maria Vulturar et al. J Pers Med. .

Abstract

Background: As the global battle against the COVID-19 pandemic endures, the spread of the Delta variant has introduced nuanced challenges, prompting a nuanced examination.

Materials and methods: We performed a multilevel logistic regression analysis encompassing 197 patients, comprising 44 vaccinated individuals (V group) and 153 unvaccinated counterparts (UV). These patients, afflicted with the Delta variant of SARS-CoV-2, were hospitalized between October 2021 and February 2022 at the COVID-19 department of a University Centre in Cluj-Napoca, Romania. We compared patient characteristics, CT lung involvement, Padua score, oxygen saturation (O2 saturation), ventilation requirements, dynamics of arterial blood gas (ABG) parameters, ICU admission rates, and mortality rates between the two groups.

Results: The UV group exhibited a statistically significant (p < 0.05) proclivity toward developing a more severe form of infection, marked by elevated rates of lung involvement, oxygen requirement, ICU admission, and mortality.

Conclusion: Our findings underscore the substantial efficacy of the vaccine in diminishing the incidence of severe disease, lowering the rates of ICU admissions, and mitigating mortality among hospitalized patients.

Keywords: COVID-19; Delta variant; ICU admission; SARS-CoV-2; mortality; severe disease; vaccines.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Study flowchart.
Figure 2
Figure 2
Relative frequency for disease form based on vaccination status.
Figure 3
Figure 3
CT scan showing the lung’s involvement distribution in vaccinated and unvaccinated patients. (The middle line of the boxplot represents the median, the upper and lower bars represent the 75th and 25th percentile, and the red dot represents the mean).
Figure 4
Figure 4
Density plot showing the Padua score distribution in the studied groups.
Figure 5
Figure 5
pH values among vaccinated and unvaccinated patients at different time points.
Figure 6
Figure 6
PaO2 values among vaccinated and unvaccinated patients at different time points.
Figure 7
Figure 7
PCO2 values among vaccinated and unvaccinated patients at different time points.
Figure 8
Figure 8
HCO3− values among vaccinated and unvaccinated patients at different time points.
Figure 9
Figure 9
SaO2 values among vaccinated and unvaccinated patients at different time points.
Figure 10
Figure 10
Kaplan–Meier plot of mortality probability based on vaccination status.
See this image and copyright information in PMC

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