Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Observational Study
. 2024 Jan 6;24(1):55.
doi: 10.1186/s12879-023-08939-w.

Characteristics, outcome, duration of hospitalization, and cycle threshold of patients with COVID-19 referred to four hospitals in Babol City: a multicenter retrospective observational study on the fourth, fifth, and sixth waves

Farzin Sadeghi #  1 , Mehrdad Halaji #  2 , Hoda Shirafkan  3 , Abazar Pournajaf  2 , Hossein Ghorbani  4 , Sara Babazadeh  4   5 , Nafiseh Ezami  6 , Kobra Fallhpour  7 , Fatemeh Fakhraie  8 , Shahrbano Gorjinejad  9 , Saghar Saber Amoli  10 , Fatemeh Hejazi Amiri  10 , Mahnaz Baghershiroodi  1 , Zahra Ahmadnia  4 , Maryam Salehi  4 , Mehdi Tourani  1 , Jalal Jafarzadeh  4 , Farzane Shanehbandpour Tabari  1 , Seyed Raheleh Ahmadian  2 , Rouzbeh Mohammadi Abandansari  4 , Farzaneh Jafarian  4 , Samaneh Rouhi  4 , Arezoo Zabihollahi  4 , Sarina Mostafanezhad  4 , Fatemeh Saeedi  5 , Arefeh Ebrahimian  10 , Zeinab Deldar  11 , Mahmoud Sadeghi Haddad Zavareh  2 , Masoumeh Bayani  2 , Mana Bazi Broun  2 , Moein Shirzad  2 , Siamak Sabbaghi  4 , Mohsen Mohammadi  12 , Rabeae Rahmani  13 , Yousef Yahyapour  14   15
Affiliations
Observational Study

Characteristics, outcome, duration of hospitalization, and cycle threshold of patients with COVID-19 referred to four hospitals in Babol City: a multicenter retrospective observational study on the fourth, fifth, and sixth waves

Farzin Sadeghi et al. BMC Infect Dis. .

Abstract

Background: The aim of the present study was to compare the epidemiological patterns of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infections, hospitalizations, deaths, and duration of hospitalization during the fourth, fifth and sixth epidemic waves of coronavirus disease 2019 (COVID-19) in Iran.

Methods: A multicenter retrospective observational study was conducted on hospitalized patients in four hospitals in the Babol district of northern Iran. The study periods were during the fourth, fifth, and sixth waves of the epidemic in Iran, (March 2021 to March 2022). A total of 13,312 patients with suspected COVID-19 were included. Patient demographics, medical history, length of hospital stay, and clinical outcomes were obtained from the hospital information system. Data on the cycle threshold (Ct) and SARS-CoV2 variant were collected for SARS-CoV2-positive cases.

Results: The highest number of hospitalized patients was reported during the fifth (Delta) wave (5231; 39.3%), while the lowest number of hospitalized patients was reported during the sixth (Omicron) wave (2143; 16.1%). In total, 6459 (48.5%) out of 13,312 hospitalized patients with suspected COVID-19 had a positive rRT-PCR result. The fifth (Delta) wave had the highest number of SARS-CoV2 rRT-PCR-positive hospitalized patients (3573, 55.3%), while the sixth (Omicron) wave had the lowest number (835, 12.9%). Moreover, 238 (3.7%) patients with laboratory-confirmed COVID-19 died. The hospital mortality rate was 6.8% in the fourth (Alpha) wave, which reduced to 2.7 and 3.5% in the fifth (Delta) and sixth (Omicron) waves, respectively (p < 0.001).

Conclusions: This is the most comprehensive study evaluating the epidemiologic characteristics of laboratory-confirmed SARS-CoV2 cases in Iran during the Alpha, Delta, and Omicron waves. The highest number of SARS-CoV2-positive hospitalized patients was in the fifth wave of COVID-19 (dominance of the Delta variant), while the sixth wave (dominance of the Omicron variant) had the lowest number. Comorbidities were similar, and cardiovascular disease, diabetes, kidney disease, and hypertension were the main risk factors in all waves.

Keywords: Alpha variant; COVID-19; Death; Delta variant; Hospitalization; Omicron variant; SARS-CoV-2.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Age group distribution of hospitalized patients with suspected (A) and confirmed (B) COVID-19–infection
Fig. 2
Fig. 2
Percentage of patients admitted to the intensive care unit (ICU) and mortality rate among SARS-CoV-2 PCR-positive (A) and total hospitalizations (B) based on epidemic waves
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Samidoust P, Nikoupour H, Hemmati H, Samidoust A. Clinical manifestations and characterization of COVID-19 in liver transplant recipients: a systematic review of case reports and case series. Ethiop J Health Sci. 2021;31:429–438. - PMC - PubMed
    1. Sifuentes-Rodríguez E, Palacios-Reyes D. COVID-19: the outbreak caused by a new coronavirus. Bol Med Hosp Infant Mex. 2020;77:47–53. - PubMed
    1. Ascencio-Montiel IJ, Ovalle-Luna OD, Rascón-Pacheco RA, Borja-Aburto VH, Chowell G. Comparative epidemiology of five waves of COVID-19 in Mexico, march 2020–august 2022. BMC Infect Dis. 2022;22:813. doi: 10.1186/s12879-022-07800-w. - DOI - PMC - PubMed
    1. Parra-Lucares A, Segura P, Rojas V, Pumarino C, Saint-Pierre G, Toro L. Emergence of SARS-CoV-2 Variants in the World: How Could This Happen? Life (Basel). 2022;12(2):194. - PMC - PubMed
    1. Chi W-Y, Li Y-D, Huang H-C, et al. COVID-19 vaccine update: vaccine effectiveness, SARS-CoV-2 variants, boosters, adverse effects, and immune correlates of protection. J Biomed Sci. 2022;29:82. doi: 10.1186/s12929-022-00853-8. - DOI - PMC - PubMed

Publication types

Supplementary concepts