Antibody response dynamics to CoronaVac vaccine and booster immunization in adults and the elderly: A long-term, longitudinal prospective study.

Background: The long-term humoral immune response after vaccination varies between vaccines and is dependent on the accuracy of the antibody test. A better understanding of the vaccine immune response may help to define vaccination strategies against coronavirus disease 2019 (COVID-19). Objective: To investigate the long-term immunological response to CoronaVac vaccine and determinants of breakthrough COVID-19 infection. Methods: A long-term, prospective cohort study involving vaccinated adult and elderly subjects was conducted to investigate the presence of anti-RBD-specific immunoglobulin (Ig)G, anti-nucleocapsid IgG and anti-spike trimeric protein IgG. Antibody level dynamics and risk factors associated with breakthrough COVID-19 infection were investigated. Results: In total, 3902 participants were included in this study. Vaccination with two doses of CoronaVac and a booster dose increased the levels of anti-RBD-specific IgG, anti-nucleocapsid IgG and anti-spike trimeric IgG significantly. In adults, anti-nucleocapsid IgG and anti-spike trimeric IgG levels decreased significantly 7 months after the second dose. In adults and the elderly, the levels of anti-spike trimeric IgG and anti-RBD IgG decreased significantly 4 and 6 months after the booster dose, respectively. Previous exposure to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and anti-spike trimeric IgG titres was independently associated with a lower probability of post-vaccination infection. Conclusions: A significant increase in antibody levels was found after two doses of CoronaVac and a booster dose. Antibody titres declined significantly 7 months post-vaccination in participants who did not receive a booster dose. Higher levels of antibodies and previous SARS-CoV-2 infection were associated with protection against breakthrough COVID-19.

Dynamics of SARS-CoV-2 Variants of Concern in Vaccination Model City in the State of Sao Paulo, Brazil.

From a country with one of the highest SARS-CoV-2 morbidity and mortality rates, Brazil has implemented one of the most successful vaccination programs. Brazil's first model city vaccination program was performed by the CoronaVac vaccine (Sinovac Biotech) in the town of Serrana, São Paulo State. To evaluate the vaccination effect on the SARS-CoV-2 molecular dynamics and clinical outcomes, we performed SARS-CoV-2 molecular surveillance on 4375 complete genomes obtained between June 2020 and April 2022 in this location. This study included the period between the initial SARS-CoV-2 introduction and during the vaccination process. We observed that the SARS-CoV-2 substitution dynamics in Serrana followed the viral molecular epidemiology in Brazil, including the initial identification of the ancestral lineages (B.1.1.28 and B.1.1.33) and epidemic waves of variants of concern (VOC) including the Gamma, Delta, and, more recently, Omicron. Most probably, as a result of the immunization campaign, the mortality during the Gamma and Delta VOC was significantly reduced compared to the rest of Brazil, which was also related to lower morbidity. Our phylogenetic analysis revealed the evolutionary history of the SARS-CoV-2 in this location and showed that multiple introduction events have occurred over time. The evaluation of the COVID-19 clinical outcome revealed that most cases were mild (88.9%, 98.1%, 99.1% to Gamma, Delta, and Omicron, respectively) regardless of the infecting VOC. In conclusion, we observed that vaccination was responsible for reducing the death toll rate and related COVID-19 morbidity, especially during the gamma and Delta VOC; however, it does not prevent the rapid substitution rate and morbidity of the Omicron VOC.

Percepções de alunos de medicina sobre marketing médico / Undergraduate medical student's perceptions regarding professional marketing

INTRODUÇÃO: Marketing médico é um assunto controverso, principalmente no que concerne a princípios éticos. Portanto, frente à competição acirrada de mercado, é necessário o preparo profissional. Conhecer a percepção dos alunos de Medicina pode auxiliar na estruturação de alternativas de capacitação. METODOLOGIA: Inicialmente, identificaram-se crenças sobre marketing médico através de grupo focal composto por 12 alunos. Com base nesses dados, dez afirmações para avaliar atitudes foram aplicadas aos alunos de uma Faculdade de Medicina pública brasileira. RESULTADOS: Observou-se falta de clareza sobre o conceito de marketing, preocupação com princípios éticos e necessidade de marketing no mercado competitivo. Na fase de aplicação, foram obtidas 280 respostas de diversos estágios do curso. Apenas 16,8% admitiram contato com o tema. Houve clareza sobre ética em relação ao paciente, influenciada positivamente pela progressão no curso, mas houve divergência na ética entre profissionais. CONCLUSÕES: Marketing médico é uma área pouco compreendida e relegada ao currículo oculto, sendo influenciada por transposições inadequadas de métodos didáticos destinados à comunicação profissional para a população leiga. Novos métodos de ensino, como a educação tutorial, podem ser uma alternativa para lidar com essas situações.

BACKGROUND: Professional marketing is a controversial topic, mainly regarding ethical principles. Therefore, increasing market competion turns professional capacitation mandatory. To know under graduation medical student's perceptions could help to develop educational alternatives to face this problem. METODOLOGY: First, professional marketing believes were identified through focus group methodology including twelve students. Based on these results, ten affirmatives were constructed to evaluate attitudes and applied to the students of a Brazilian public medicine school. RESULTS: It was observed lack of a clear definition of marketing, preoccupation regarding ethical principles and need to employ marketing strategies in a competitive market. At the survey stage, 280 answers from different stages of the course were obtained. Only 16.8% admitted to have had previous contact with the topic. Clear ethical standards for medical-patient relationship were determined, increasing with course progression. However inter-professional ethical principles was more subject to confusion. CONCLUSION: Professional marketing is poorly understood and it is relegated to the occult curricula, being influenced by didactic methods inadequately transposed for marketing strategies. Newer educational methods, like mentoring, could be an alternative to deal with these situations.Tutoria.