Macular perfusion changes in people administered two types of COVID-19 vaccines: optical coherence tomography angiography study

ABSTRACT Purpose: To evaluate macular chorioretinal flow changes on optical coherence tomography angiography, in participants who received inactivated and messenger RNA (mRNA) vaccines to prevent coronavirus disease 2019 (COVID-19). Methods: In this prospective cohort study, healthy participants who received two doses of an inactivated COVID-19 vaccine (CoronaVac) and then one dose of an mRNA vaccine (BNT162b2) were examined before and after each vaccination. Ophthalmologic examination and imaging with optical coherence tomography angiography were performed during each visit. We evaluated vascular densities in the superficial and deep capillary plexuses in foveal, parafoveal, and perifoveal areas; the foveal avascular zone; and choriocapillaris flows (in 1- and 6-mm-diameter areas). Results: One eye in each of the 24 participants was assessed. Superficial capillary plexus vascular densities in the parafoveal area were significantly lower after the second dose of the CoronaVac vaccine than after the first dose. In the deep capillary plexus, vascular attenuation was observed only in the parafoveal region after the first CoronaVac dose. However, in all regions, the deep capillary plexus vascular densities and subfoveal choriocapillaris flow were significantly decreased after the second CoronaVac dose. After the BNT162b2 dose, the superficial capillary plexus vascular densities, the deep capillary plexus vascular densities, and subfoveal choriocapillaris flow of most regions were significantly lower than those before vaccinations. Conclusion: Vascular attenuation, observed particularly after the second dose of the CoronaVac vaccine, may explain the pathogenesis of postvaccine ocular ischemic disorders reported in the literature. However, these disorders are extremely rare, and the incidence of thrombotic events caused by COVID-19 itself is higher.

Frequency And Factors Associated With Adverse Reactions After Administration of Inactivated COVID-19 Vaccine Among Health Workers

ABSTRACT Background: The 2019 coronavirus (COVID-19) has precipitated a significant public health crisis. Our study aimed to evaluate the prevalence and risk factors associated with adverse reactions to the inactivated CoronaVac vaccine. Methods: The study involved voluntary health workers who received CoronaVac vaccine. We documented the sociodemographic information of 2,019 participants who volunteered for our study. Of these, 1,964 and 1,702 participants were interviewed by phone 1 month after the first and second dose, respectively, during which they were queried about any adverse reactions. Results: Within the first week after the first dose, adverse reactions were observed in 856 (43.3%) participants, with 133 (6.7%) experiencing them during the second week, and 96 (4.9%) people at the end of the first month. For the second dose, 276 individuals (16.2%) reported adverse reactions. The prevalence of both local and systemic adverse events ranged from 9.5-11.2% overall. Fatigue was the most common adverse reaction overall, while pain at the injection site was the most frequent local adverse reaction. Conclusions: The evaluation of both systemic and local side effects revealed no significant adverse reactions to the inactivated CoronaVac vaccine (Sinovac Life Sciences, Beijing, China). Our study found that the incidence of systemic and local adverse responses to the CoronaVac vaccination was lower than the rates reported in studies involving the recombinant adenovirus type-5, BNT162b1, and ChAdOx1nCoV-19 COVID-19 vaccines, all of which underwent the World Health Organization LULUC/PQ evaluation process.

Comparison of humoral immune response in heterologous and homologous COVID-19 booster vaccine groups using CoronaVac and mRNA-based BNT162b2 vaccines

ABSTRACT Background: Heterologous COVID-19 booster vaccination is an alternative strategy to homologous vaccination, especially in developing countries, due to shortages, delays, or unequal distribution of COVID-19 vaccines. We compared cohorts vaccinated with different vaccine combinations to investigate whether a heterologous booster dose of mRNA-based BNT162b2 vaccine boosts the immune response in individuals primed with the CoronaVac vaccine. Methods: Anti-RBD IgG is generally measured 4 weeks after primary immunization and 4 weeks after booster vaccination. Data on anti-receptor-binding domain (anti-RBD) IgG antibody titers and clinical characteristics were provided by infection control units. Results: The highest median anti-RBD IgG antibody titers (14589 AU/mL) after primary immunization was observed in the group vaccinated with two doses of BNT162b2 vaccine. Antibody titers were lower 4 months or more after the second CoronaVac vaccine dose in CoronaVac recipients with or without previous COVID-19. In the homologous COVID-19 booster vaccine group (primed with two doses of CoronaVac 4 weeks apart and a single booster dose of CoronaVac) the median anti-RBD titers decreased from 1025 to 242 AU/mL before the booster dose. In the heterologous group (primed with two doses of CoronaVac 4 weeks apart and a single booster dose of BNT162b2), the median anti-RBD titer increased to 31624 AU/mL, a 132-fold increase, 16 days after the booster dose. Conclusions: After the second dose of CoronaVac, protective neutralizing antibody levels decrease over time, and a booster dose is required. Heterologous COVID-19 booster vaccination with BNT162b2 is effective at boosting neutralizing antibody levels.

Humoral responses to the CoronoVac vaccine in healthcare workers

ABSTRACT Background: This study aimed to assess the immunoglobulin G (IgG) antibody response rate in emergency department (ED) healthcare workers (HCWs) and potential adverse effects after CoronaVac vaccination. Methods: All included HCWs were grouped based on the previous history of coronavirus disease 2019 (COVID-19) and the number of vaccinations. Furthermore, the IgG antibody response was evaluated based on the sex and smoking status of HCWs. Those with a cut-off index of ≥1.00 after vaccination with CoronaVac were considered to have had COVID-19 and had an adequate humoral response. Results: Among 224 ED HCWs, 18% experienced the adverse effects of CoronaVac vaccine, the most prevalent being pain in the injection site. The IgG antibody response rate was 20% after the first dose of vaccine, while the response rate increased to 90% after the second dose. Female HCWs had higher IgG response rates compared with male HCWs (53.8 [15.9-147.0] vs 31.2 [4.5-124.0]). Non-smokers had higher IgG response rate compared with smokers (49.0 [11.5-160.5] vs 23.1 [7.4-98.5]). Conclusion: A single dose of CoronaVac does not produce a sufficient antibody response; hence, two doses are recommended. Men have a lower IgG response compared with women. Smokers had a lower IgG response rate compared with non-smokers. Therefore, it may be necessary to carefully assess the humoral responses of men and smokers when implementing a community vaccination program.

Generation of neutralizing antibodies against Omicron, Gamma and Delta SARS-CoV-2 variants following CoronaVac vaccination

ABSTRACT Vaccination is a fundamental tool to prevent SARS-CoV-2 infection and to limit the COVID-19 pandemic. The emergence of SARS-CoV-2 variants with multiple mutations has raised serious concerns about the ability of neutralizing antibody responses elicited by prior vaccination to effectively combat these variants. The neutralizing capacity against the Gamma, Delta and Omicron variants of sera from individuals immunized with the CoronaVac vaccine remains incompletely determined. The present study evaluated 41 health care workers at the Faculdade de Medicina of the Universidade de Sao Paulo, in Sao Paulo, Brazil, naive to previous SARS- CoV-2 infection, who were vaccinated with two doses of the CoronaVac SARS-CoV-2 vaccine 28 days apart. Neutralizing antibody levels against the Gamma, Delta, and Omicron variants were measured at 32 and 186 days after the second vaccination. We also measured neutralizing antibodies against Omicron in 34 of these individuals following a subsequent booster immunization with the Pfizer vaccine. Quantification of neutralizing antibodies was performed using the Cytopathic Effect-based Virus Neutralization test. Neutralization antibody activity against the Gamma, Delta and Omicron variants was observed in 78.0%, 65.9% and 58.5% of serum samples, respectively, obtained at a mean of 32 days after the second immunization. This decreased to 17.1%, 24.4% and 2.4% of sera having activity against Delta, Gamma and Omicron, respectively, at 186 days post-vaccination. The median neutralizing antibody titers at 32 days were 1:40, 1:20 and 1:20 against Gamma, Delta and Omicron, respectively, and decreased to an undetectable median level against all variants at the later time. A booster immunization with the Pfizer vaccine elicited neutralizing antibodies against Omicron in 85% of subjects tested 60 days after vaccination. We conclude that two doses of the CoronaVac vaccine results in limited protection of short duration against the Gamma, Delta and Omicron SARS-CoV-2 variants. A booster dose with the Pfizer vaccine induced antibody neutralizing activity against Omicron in most patients which was measurable 60 days after the booster.

Immune thrombocytopenic purpura following CoronaVac vaccination: a case report

Immune thrombocytopenic purpura (ITP), an autoimmune disorder, has been documented as a result of SARS-CoV-2 infection and a vaccination side effect. The COVID-19 pandemic has led to the creation of CoronaVac vaccine and has been widely administered in Brazil.Patient, in the case, is an 82-years-old female who received the vaccine two days before an acute episode of gingivorrhagia and diffuse cutaneous petechiae. Other exams were made to look for other causes of secondary thrombocytopenia and all the results were normal. The patient showed improvement on the platelet levels three day after the beginning of the treatment with high dosage methylprednisolone.Knowing that other kinds of vaccine can generate ITP, the SARS-CoV-2 vaccine could be related to the symptoms.

Post-vaccination incidence and side effects of COVID-19 in a cohort of Brazilian healthcare professionals: an internet-based survey

Abstract Objective So far, at least 18 different severe acute respiratory syndrome coronavirus-2 vaccines have been approved. Until October 2022, 12.8 billion doses had been administered all over the world. Vaccination of high-risk groups and healthcare professionals was initially prioritized. This cross-sectional survey aimed to investigate the occurrence of vaccine side effects, as well as the incidence of COVID-19 among vaccinated healthcare professionals. Methods A survey was structured and shared with healthcare professionals using a digital platform to collect data between May and June 2021. Results This study included 6,115 participants. The most prevalent age group was 30-39 years (31.3%), 67.3% were female and 73.2% accounted for physicians, and nearly half worked in frontline care for COVID-19. Approximately, two-thirds of them were vaccinated with CoronaVac, and about 60% reported at least one side effect following the vaccination. Nevertheless, minor reactions were more frequent, such as pain at site of injection, fatigue, and headache. Our data could be used to inform people on the likelihood of side effects of COVID-19 vaccines, particularly CoronaVac, since this is the largest study about vaccine reactions using this vaccine, to our best knowledge. Conclusion The incidence of side effects in Brazilian healthcare professionals was 60%, and the most common side effects included local swelling/pain, fatigue/tiredness, fever, headache, and limb pain.

Primeiros casos de rejeição em transplante penetrante após vacina contra COVID-19 / First cases of penetrating corneal transplant rejection after COVID-19 vaccines

RESUMO Este artigo descreve dois casos de reação imunológica de rejeição de transplante penetrante após a aplicação de dois tipos de vacina contra a COVID-19 - CoronaVac (Sinopharm/Butantan) e MRNA BNT162&2 (Pfizer-BioNTech) - com intervalo de 1 e 10 dias, respectivamente. A rejeição se manifestou com hiperemia, edema corneano e embaçamento da visão, que responderam rapidamente ao uso de corticoide tópico e subconjuntival. Até onde sabemos, este é o primeiro relato de rejeição de transplante penetrante de córnea pós-vacina anti-COVID-19. Recomendamos, presentemente, como prevenção, colírio de prednisolona a 1% 4 dias antes e durante 2 semanas após receber qualquer tipo de vacina para a COVID-19.

ABSTRACT This paper describes two cases of allograft corneal transplant rejection after the application of two types of COVID-19 vaccines - Coronavac (Sinopharm/Butantan) and MRNA BNT162&2 (Pfizer-BioNTech) vaccines - with an interval of 1 to 10 days, respectively. The rejection manifested in the form of corneal edema, hyperemia and blurred vision, which responded rapidly to the use of topical and subconjunctival corticosteroid. As far as we know, this is the first published report of immunological rejection of penetrating corneal transplant after COVID-19 vaccination. As a preventative measure, we now recommend the use of 1% prednisolone eye drop 4 days before and during 2 weeks after having received any type of COVID-19 vaccine.