Evaluation of PastoCovac plus vaccine as a booster dose on vaccinated individuals with inactivated COVID-19 vaccine
Behrokh Farahmand, Mona Sadat Larijani, Fatemeh Fotouhi, Alireza Biglari, Rahim Sorouri, Fahimeh Bagheri Amiri, Ali Eslamifar, Tahmineh Jalali, Mostafa Salehi-Vaziri, Mohammad Banifazl, Sarah Dahmardeh, Azita Eshratkhah Mohammadnejad, Anahita Bavand, Mahsa Tavakoli, Vicente Vérez-Bencomo, Ehsan Mostafavi, Hassan Noori Daloii, Fatemeh Ashrafian, Masoumeh Saberpour, Amitis Ramezani
Abstract
COVID-19 pandemic has been managed through global vaccination programs. However, the antibody waning in various types of vaccines came to notice. Hereby, PastoCovac Plus as a protein subunit vaccine was investigated in immunized health care workers by COVAXIN (BBV152). The booster vaccine was recommended at least three months post the second dose of COVAXIN. Sera collection was done before and after each injection. SARS-CoV-2 PCR test was done monthly to detect any asymptomatic and symptomatic vaccine breakthrough. 47.9 and 24.3% of the participants were seronegative for anti-N and anti-S antibodies three months after the second dose of COVAXIN, respectively. On average, fold-rises of 70, 93, 8 and mean-rises of 23.32, 892.4, 5.59 were recorded regarding neutralizing antibody, quantitative and semi-quantitative anti-Spike antibody, respectively. Anti-Spike and neutralizing antibodies seroconversion was seen 59.3% and 45.7%, respectively. The vaccine breakthrough assessment showed that all the isolated samples belonged to SARS-CoV-2 Delta variant. PastoCovac Plus boosting is strongly recommended in combination with inactivated vaccine platforms against SARS-CoV-2.