Evaluation of Adverse Effects Reported by Participants Following the Administration of Two Doses of TURKOVAC Vaccine via a Telephone Survey Study

TURKOVAC vaccine is a COVID-19 vaccine developed, produced, and licensed in Türkiye, which is inactive, meaning it contains an inactivated virus that does not cause disease but generates an immune response.

The aim of this study is to evaluate the distribution and certain characteristics of adverse effects reported by participants after the second dose following the administration of the TURKOVAC vaccine in a total of 22 hospitals affiliated with the Ministry of Health, located in 17 provinces in Türkiye.

In this study, between January 10 and February 18, 2022, a survey querying adverse effects that may occur after vaccination was administered verbally via telephone on the third and seventh days following the administration of the first and second doses to a group of 20,000 people to whom the TURKOVAC vaccine was administered. In the survey, other adverse effects specified by the participants were also recorded. Following the first dose, 6,023 people on the third day and 5,345 people on the seventh day agreed to participate in the telephone survey. After the second dose, 6,501 people participated in the study on both the third and seventh days.

Following the first dose of the TURKOVAC vaccine; it was reported that an adverse effect was experienced by approximately one in every three participants (36.6 percent) on the third day and by one in every five participants (22.5 percent) on the seventh day. The percentage of those reporting any adverse effects following the second dose of the vaccine was also found to be similar for the third and seventh days.

For both doses, the most frequently reported adverse effects were local adverse effects specific to the site where the vaccine was administered (29.7% and 29.0% for the first and second doses on the third day, respectively; 13.1% and 13.6% for the first and second doses on the seventh day, respectively). Among the local adverse effects, the most frequently reported were pain at the site where the vaccine was administered (27.9% and 28.6% for the first and second doses on the third day, respectively; 12.4% and 13.4% for the first and second doses on the seventh day, respectively), stiffness (4.8% and 3.4% for the first and second doses on the third day, respectively; 2.7% and 2.1% for the first and second doses on the seventh day, respectively), and swelling (3.5% and 2.7% for the first and second doses on the third day, respectively; 2.0% and 1.8% for the first and second doses on the seventh day, respectively).

Weakness/fatigue (9.6 percent and 8.9 percent for the first and second doses on the third day, respectively; 8.3 percent and 8.4 percent for the first and second doses on the seventh day, respectively) and headache (7.9 percent and 7.2 percent for the first and second doses on the third day, respectively; 8.0 percent and 7.1 percent for the first and second doses on the seventh day, respectively) were the most frequently reported systemic adverse effects.

For both doses, it was found that being at the young age group, receiving repeated doses of the vaccine, and being of female gender increased the reporting of any adverse effects and specifically the occurrence of pain at the site where the vaccine was administered. Additionally, being of female gender was found to be associated with increased pain at the site where the vaccine was administered, swelling, fever, and the state of affecting daily life.

In this study, a rapid evaluation of the adverse effects reported after each dose of the TURKOVAC vaccine was conducted. It was observed that for both doses of the vaccine, it has a good safety level within the first 7 days following vaccination. It is also thought that these findings represent valuable information for the public and healthcare workers and will contribute to an increase in confidence toward the vaccine.

This study was presented at the 33rd European Congress of Clinical Microbiology and Infectious Diseases under the following title:

Coskun A., Temel F., Ozelci P., Topal S., Ates İ., Cakir Koc R., Akdogan E., Kara A. Assessment of participant-reported adverse events following the two doses of inactivated SARS-CoV-2 vaccine through a telephone survey in Turkey. 33rd European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), 15-18 April 2023, Copenhagen, Denmark.