Assessment of long-term adverse events regarding different COVID-19 vaccine regimens within an 18-month follow-up study

Assessment of long-term adverse events regarding different COVID-19 vaccine regimens within an 18-month follow-up study

Pathogens and Disease, May 2023

37230943

Mona Sadat Larijani, Rahim Sorouri, Sana Eybpoosh, Delaram Doroud, Ladan Moradi, Mozhgan Ahmadinezhad, Anahita Bavand, Fatemeh Ashrafian, Parinaz Tajmehrabi Namini, Mahsan Zali, Amitis Ramezani

Early reports on COVID-19 vaccines presented the short-term adverse events (AEs). This follow-up study investigated a standard regimen based on protein subunit vaccines, PastoCovac and PastoCovac Plus, and the combinational vaccine regimens including AstraZeneca/PastoCovac Plus and Sinopharm/PastoCovac Plus. The participants were followed up to 6 months post-the booster shot. All the AEs were collected through in-depth interview using a valid researcher-made questionnaire and were evaluated regarding the association with the vaccines. Of the 509 individuals, 6.2% of the combinational vaccine participants had late AEs from whom 3.3% suffered from cutaneous manifestations followed by 1.1% arthralgia complains, 1.1% with neurologic disorders, 0.3% ocular problem and 0.3% metabolic complication, with no significant difference between the vaccine regimens. Of the standard regimen, 2% of the individuals experienced late AEs as (1%), neurologic disorders (0.3%), metabolic problem (0.3%) and joints involvements (0.3%). Notably, 75% of the AEs were persistent up to the end of the study. A low number of late AEs were captured in 18 months as 12 improbable, 5 unclassifiable, 4 possible and 3 probable associated AEs with the vaccine regimens. The benefits of COVID-19 vaccination are far from the potential risks and the late AEs seem to be uncommon.