Study of Humoral Immunity against Coronavirus Infection COVID-19 in Vaccinated Individuals with Vaccines Available in the Republic of Belarus (Sputnik V (Gam-COVID-Vac), RF and Sinopharm (BBIBP-CorV), PRC)

Relevance. Many countries around the world are developing effective vaccines against SARS-CoV-2. The measure of the effectiveness of the vaccination process has traditionally been antibody production. The frequency and intensity of adverse reactions is also an important factor in making a decision regarding a vaccine. This study presents the results of the evaluation of the formation of humoral immunity and the occurrence of reactions in response to the administration of Sputnik V (Gam-COVID-Vac), RF, and Sinopharm (BBIBP-CorV), PRC. Aim. Analyze immunogenicity and reactogenicity of COVID-19 vaccines used in the Republic of Belarus (Sputnik V and Sinopharm). Materials and methods. Evaluation of postvaccination immune response by enzyme immunoassay and differential enzyme immunoassay for class G immunoglobulins to S-and N-proteins SARS-CoV-2. Blood plasma of the study participants was used as biological material. Blood sampling was performed 3 times: immediately before the first vaccine dose, on day 42, and 6 months after the first vaccine dose. To evaluate the frequency and intensity of postvaccination reactions, study participants were questioned. Results. At 42 days after administration of both vaccines, antibody levels are rising, with a significantly higher quantitative IgG count for the Sputnik V vaccine. This trend is also observed 6 months after the first dose of both vaccines, both among those previously infected with SARS-CoV-2 and those without a history of COVID-19. The comparison of Sputnik V and Sinopharm vaccine groups in terms of IgG (BAU/ml) levels to S-and N-proteins revealed a statistically significant difference in IgG levels to S-protein: the Sputnik V vaccine group had significantly higher IgG levels to S-protein than the Sinopharm vaccine group (p = 0.0000196). The incidence of adverse reactions in this study was 45%. All reactions noted were mild to moderate in severity. The most common were soreness and redness at the injection site, elevated body temperature, and a combination of several reactions. The increased body temperature after vaccination was more common among those vaccinated with the Sputnik V vaccine. Conclusion. Compared to Sinopharm, Sputnik V vaccine produces higher antibody level. Adverse reactions were observed in both vaccinated groups. However, significant statistical differences were found with regard to fever in the Sputnik V vaccine group, which occurred more frequently. © 2023, Numikom. All rights reserved.

COVID-19 Breakthrough Infection Among Vaccinated Population in the United Arab Emirates.

BACKGROUND: Despite significant efforts to contain the Coronavirus Disease 2019 (COVID-19) pandemic through mass vaccination, numerous nations throughout the world have recorded breakout infections. The incidence and severity of COVID-19 breakthrough infections in the United Arab Emirates (UAE) remain unknown despite extensive COVID-19 vaccine coverage. The goal of this research is to establish the characteristics of COVID-19 breakthrough infections in the UAE's vaccinated population. METHODS: Between February and March 2022, we conducted a descriptive cross-sectional study in the UAE with 1533 participants to examine the characteristics of COVID-19 breakthrough infection among the vaccinated population. RESULTS: The vaccination coverage was 97.97%, and the COVID-19 breakthrough infection rate was 32.1%, requiring hospitalization in 7.7% of cases. The bulk of the 492 COVID-19 breakthrough infections reported was among young adults (67%), with the majority experiencing mild to moderate symptoms (70.7%) or remaining asymptomatic (21.5%). CONCLUSIONS: COVID-19 breakthrough infection were reported in younger age, male sex, non-healthcare professions, vaccination with inactivated whole virus vaccine (Sinopharm), and not receiving a booster dose. Information on breakthrough infection in the UAE might influence public health decisions and motivate measures such as providing additional booster doses of the vaccines to the people.

SARS-CoV-2 antibody response after BBIBP-CorV (Sinopharm) vaccination in cancer patients: A case-control study.

Background: Long-term safety and efficacy of BBIBP-CorV vaccine especially in individuals with chronic diseases, like cancer, is under investigation. In the present prospective study, we aimed to evaluate severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) antibody response with BBIBP-CorV vaccine in Iranian cancer patients. Methods: All the patients registered to receive BBIBP-CorV (Sinopharm) vaccine were divided into two groups of with (cases = 107) and without (controls = 45) history of cancer. Serum levels of SARS-CoV anti-spike recombinant receptor binding domain (anti-sRBD) and anti-nucleocapsid (anti-N) IgG serum levels were measured on days 0 (phase 0), 28-32 (phase I), and 56-64 (phase II) of vaccination. The data were analyzed using SPSS, version 22. Results: Totally, 152 individuals (67.1% females) with the mean age of 46.71 ± 15.36 years were included. Solid cancers included 87.8% of the cancer cases (46.7% gynecological and 31.8% gastrointestinal cancer). At Phases I and II, positive anti-sRBD IgG and anti-N IgG were significantly lower among the cases in total analysis. Side effects were not significantly different between the cases and controls. The lowest positive anti-sRBD IgG test was observed among the cancer patients who were simultaneously receiving chemotherapy (35.3%). Anti-sRBD IgG and anti-N IgG serum levels significantly increased at phases I and II in total analysis and in each group. In addition, serum anti-sRBD IgG increased during the three phases and it was significantly higher in the control group. Conclusion: Full vaccination of COVID-19 by BBIBP-CorV in immunocompromised patients such as cancer patients is safe and effective and could induce antibody response but in lower levels compared to healthy people. Probable causes to have minor antibody response found in males, older ages, individuals with BMI ≥ 25, those without past history of COVID-19 and with hematologic cancers. No significant side effects after vaccination were seen.

Side effects and perceptions following Sinopharm COVID-19 vaccination.

OBJECTIVES: Vaccines are one of the best interventions developed for eradicating COVID-19. This study aimed to provide evidence on Sinopharm COVID-19 vaccine side effects. METHODS: A cross-sectional survey study was conducted between January and April 2021 to collect data on the effects of the COVID-19 vaccine among individuals in the United Arab Emirates. Demographic data, vaccination and the response of people unwilling to take the COVID-19 vaccine were reported. RESULTS: Side effects post first vaccine dose of normal injection site pain, fatigue and headache were more common in participants aged ≤49 years versus >49 years, while pain at the vaccination site, fatigue, lethargy, headache and tenderness were the most common side effects post second dose in both groups. All side effects for both doses were more prevalent among participants aged ≤49 years. Side effects were more common in females compared with males for both doses. The most common reason for being unwilling to take the COVID-19 vaccine was that vaccines are not effective. CONCLUSION: Post-vaccination side effects for the first and second doses were mild and predictable, and there were no hospitalization cases; this data will help reduce vaccine hesitancy.

Persistence of immune responses to the Sinopharm/BBIBP-CorV vaccine.

BACKGROUND: To determine the kinetics and persistence of immune responses following the Sinopharm/BBIBP-CorV, we investigated immune responses in a cohort of Sri Lankan individuals. METHODS: SARS-CoV-2 specific total antibodies were measured in 20-39 years (n = 61), 40-59 years (n = 120) and those >60 years of age (n = 22) by enzyme-linked immunosorbent assay, 12 weeks after the second dose of the vaccine. Angiotensin-converting enzyme 2 (ACE2) receptor blocking antibodies (ACE2R-Ab), antibodies to the receptor-binding domain (RBD) of the ancestral virus (WT) and variants of concern, were measured in a sub cohort. T cell responses and memory B cell responses were assessed by ELISpot assays. RESULTS: A total of 193/203 (95.07%) of individuals had detectable SARS-CoV-2 specific total antibodies, while 67/110 (60.9%) had ACE2R-Ab. A total of 14.3%-16.7% individuals in the 20-39 age groups had detectable antibodies to the RBD of the WT and variants of concern, while the positivity rates of those ≥60 years of age was <10%. A total of 14/49 (28.6%) had Interferon gamma ELISpot responses to overlapping peptides of the spike protein, while memory B cell responses were detected in 9/20 to the S1 recombinant protein. The total antibody levels and ACE2R-Ab declined from 2 to 12 weeks from the second dose, while ex vivo T cell responses remained unchanged. The decline in ACE2R-Ab levels was significant among the 40-59 (p = .0007) and ≥60 (p = .005) age groups. CONCLUSIONS: Antibody responses declined in all age groups, especially in those ≥60 years, while T cell responses persisted. The effect of waning of immunity on hospitalization and severe disease should be assessed by long term efficacy studies.

Impact of the Sinopharm's BBIBP-CorV vaccine in preventing hospital admissions and death in infected vaccinees: Results from a retrospective study in the emirate of Abu Dhabi, United Arab Emirates (UAE).

BACKGROUND: This is a community-based, retrospective, observational study conducted to determine effectiveness of the BBIBP-CorV inactivated vaccine in the real-world setting against hospital admissions and death. STUDY DESIGN: Study participants were selected from 214,940 PCR-positive cases of COVID-19 reported to the Department of Health, Abu Dhabi Emirate, United Arab Emirates (UAE) between September 01, 2020 and May 1, 2021. Of these, 176,640 individuals were included in the study who were aged ≥ 15 years with confirmed COVID-19 positive status who had records linked to their vaccination status. Those with incomplete or missing records were excluded (n = 38,300). Study participants were divided into three groups depending upon their vaccination status: fully vaccinated (two doses), partially vaccinated (single dose), and non-vaccinated. Study outcomes included COVID-19-related admissions to hospital general and critical care wards and death. Vaccine effectiveness for each outcome was based on the incidence density per 1000 person-years. RESULTS: The fully-, partially- and non-vaccinated groups included 62,931, 21,768 and 91,941 individuals, respectively. Based on the incidence rate ratios, the vaccine effectiveness in fully vaccinated individuals was 80%, 92%, and 97% in preventing COVID-19-related hospital admissions, critical care admissions, and death, respectively, when compared to the non-vaccinated group. No protection was observed for critical and non-critical care hospital admissions for the partially vaccinated group, while some protection against death was apparent, although statistically insignificant. CONCLUSIONS: In a COVID-19 pandemic, use of the Sinopharm BBIBP-CorV inactivated vaccine is effective in preventing severe disease and death in a two-dose regimen. Lack of protection with the single dose may be explained by insufficient seroconversion and/or neutralizing antibody responses, behavioral factors (i.e., false sense of protection), and/or other biological factors (emergence of variants, possibility of reinfection, duration of vaccine protection, etc.).