Study design
The present study was approved by the Institutional Ethics Committee of
Dr D Y Patil Vidyapeeth (Ref No-DYPV/EC/634/2021 dated 25 February 2021)
and recruited hospitalized patients with COVID-19 during March 2021 to
February 2022 at Dr. D. Y. Patil Medical College, Hospital and Research
Centre, Pune. The participants were ≥18-years-old male and female
subjects who provided written informed consent before enrolment. The
study was carried out in compliance with good clinical practices,
including the International Conference on Harmonization Guidelines and
the Declaration of Helsinki. COVID-19 patients were enrolled into the
study during the period of hospitalization and the first blood samples
were drawn for immunological investigations, which was followed by two
additional samples collected at 1 month and 6-8 months, respectively
after inclusion in the study (Graphical Abstract).