Awareness rate of PCV13 and influencing factors of vaccination intention among parents of infants and young children in Huangpu District , Shanghai / 公共卫生与预防医学

Objective To understand the awareness rate and willingness of parents of school-age infants and young children in Huangpu District, Shanghai to receive the 13 valent pneumococcal conjugate vaccine (PCV13) and its influencing factors, and to provide basic data for formulating community health education policies. Methods A stratified random sampling method was used to conduct a full coverage questionnaire survey on the PVC13 awareness rate and vaccination willingness of 1030 parents of infants and young children in 10 communities. Results A total of 1000 questionnaire surveys were completed, with an accurate response rate of 97.08%. The awareness rate of PCV13 was 85.50%, and the awareness rate of complications was less than 80%. The PCV13 vaccination rate was 55.60%. 38.74% of the reasons for not being vaccinated were concerned about vaccine side effects, and 32.21% were concerned about vaccine quality. The higher the education level of parents and the per capita annual income of the family, the higher the awareness rate of pneumococcal vaccine knowledge and the willingness to receive vaccination. Parents with registered residence in other places had low willingness to vaccinate PCV13. Conclusion The public has a higher awareness of PCV13 and a higher willingness to receive vaccination. It is necessary to strengthen the scientific popularization of complications of pneumococcal pneumonia and vaccine safety, strengthen vaccine safety supervision and disclosure of regulatory results, and strengthen PCV13 science popularization for parents of infants and young children with registered residence outside the city.

Neumonía bacteriana en niños en Ecuador: una mirada al impacto de las vacunas / Bacterial pneumonia in children in Ecuador: a look at the impact of vaccines

INTRODUCCIÓN: La neumonía adquirida en la comunidad es una de las enfermedades con mayor prevalencia en la comunidad pediátrica en nuestro país. De las diferentes etiologías que pueden causarlas, la neumonía ocasionada por Streptococcus pneumoniae puede ser prevenida con el uso de inmunización. Actualmente se disponen de tres tipos de vacunas antineumocócicas conjugadas autorizadas de uso pediátrico de forma sistemática. OBJETIVO: Identificar la prevalencia de neumonía bacteriana en niños bajo 5 años de edad, que requirieron hospitalización comparando la vacuna neumocócica recibida: 10 valente (PCV10) versus 13 valente (PCV13). PACIENTES Y MÉTODOS: Estudio de descriptivo, retrospectivo. Se incluyeron pacientes hospitalizados bajo 5 años de edad, con diagnóstico de neumonía bacteriana mediante codificación CIE10 en un hospital de tercer nivel de la ciudad de Quito-Ecuador, durante el año 2019. RESULTADOS: Se estudiaron 175 pacientes de los cuales 74 cumplieron con criterios clínicos de neumonía, de estos 46 recibieron PCV10 y 28 recibieron vacuna PCV13. DISCUSIÓN Y CONCLUSIONES: La prevalencia de neumonía bacteriana fue mayor en los pacientes inmunizados con PCV10 lo que sugiere una relación de menor probabilidad de neumonía con el uso de la vacuna PCV13.

BACKGROUND: Community-acquired pneumonia is one of the most prevalent diseases in the pediatric community in our country, of the different etiologies that can cause them, pneumonia caused by Streptococcus pneumoniae can be prevented with the use of immunization. Currently there are three types of authorized pneumococcal conjugate vaccines for pediatric use in a systematic way. AIM: To identify the prevalence of bacterial pneumonia in children under 5 years of age who required hospitalization by comparing the pneumococcal vaccine received: 10 valent (PCV10) versus 13 valent (PCV13). METHODS: Descriptive, retrospective study. Hospitalized patients under 5 years of age with a diagnosis of bacterial pneumonia by ICD10 coding in a third level hospital in the city of Quito - Ecuador during 2019 were included. Results: 175 patients were studied, of which 74 patients met clinical criteria for pneumonia, of these 46 received PCV10 and 28 received PCV13 vaccine. DISCUSSION AND CONCLUSIONS: The prevalence of bacterial pneumonia was higher in patients immunized with PCV10, suggesting a relationship of lower probability of pneumonia with the use of the PCV13 vaccine.

PCV13 (13-valent pneumococcal conjugate vaccine) containing capsular polysaccharides of Streptococ-cus pneumoniae serotypes 6A and 6B confers cross-protection against newly discovered serotypes 6C and 6D / 中华微生物学和免疫学杂志

Objective To investigate whether capsular polysaccharides of Streptococcus pneumoniae serotypes 6A and 6B contained in 13-valent pneumococcal conjugate vaccine ( PCV13 ) could induce cross- protective antibodies against newly discovered serotypes 6C and 6D and the differences between them. Methods New Zealand rabbits were radomly divided into three groups and respectively muscularly administrated with three doses of PCV13, PCV6A and PCV6B on days 0, 14 and 28. PCV6A and PCV6B were conjugates of capsular polysaccharides of serotypes 6A and 6B chemically coupled with diphtheria toxin mutant CRM197. Serum samples were collected on days 0 and 35. Enzyme-linked immunosorbent assay (ELISA) recommended by World Health Organization (WHO) was used to quantitatively measure serotype-specific antibodies to capsular polysaccharides of serotypes 6A, 6B, 6C and 6D. Opsonophagocytosis assay ( OPA) of WHO pneumococcal serology reference laboratory was used to determine antibody functional activities targeting serotypes 6A, 6B, 6C and 6D. Results Immunization rabbits with PCV13 induced the secretion of antibodies to capsular polysaccharides of serotypes 6A and 6B. These antibodies were able to not only cross-react with capsular polysaccharides of serotypes 6C and 6D but also recognize and bind to target Streptococcus pneumoniae serotypes 6A, 6B, 6C and 6D, resulting in the activation of complements and further phagocytosis of target bacteria by differentiated HL60 cells. Bactericid-al titers were largely even among these serotypes except for serotype 6D which was slightly lower. PCV6A could induce antibody against capsular polysaccharide of serotype 6A, which was able to cross-react with capsular pol-ysaccharides of serotypes 6B, 6C and 6D and showed higher bactericidal titers to serotypes 6A, 6B and 6C over serotype 6D. PCV6B could induce antibody against capsular polysaccharide of serotype 6B, which was able to cross-react with capsular polysaccharides of serotypes 6A, 6C and 6D and showed higher bactericidal titers to se-rotypes 6A, 6B and 6C over serotype 6D. Antibody concentrations and bactericidal titers specific to serotypes 6A, 6B, 6C and 6D were significantly increased following immunization with PCV13, PCV6A or PCV6B (P<0. 01). Conclusion PCV13 containing pneumococcal serotypes 6A and 6B induced antibodies against capsular polysaccharides of serotypes 6A and 6B in New Zealand rabbits, which were able to cross-react with capsular polysaccharides of serotypes 6C and 6D and provide cross-protection to bacteria of serotypes 6C and 6D. Both serotypes of 6A and 6B contained in PCV13 contributed to the induction of cross-protective antibodies, especially to serotype 6C.

Establishment of rabbit model for immunogenicity evaluation of pneumococcal conjugate vaccine / 中华微生物学和免疫学杂志

Objective To establish an animal model for evaluating immunogenicity of pneumococcal conjugate vaccine.Methods New Zealand rabbits were intramuscularly administrated with three doses of 13-valent pneumococcal conjugate vaccine (PCV13) with two weeks interval between each injection.Serum samples were collected at different time points before and after vaccination.Quantitative enzyme-linked immunosorbent assay (ELISA) and opsonophagocytosis assay (OPA) that were in conformity with the World Health Organization (WHO) standards were used to detect the concentrations of serotype-specific antibodies and their bactericidal activities.Results The concentrations (Geometric mean concentration, GMC) of serotype-specific antibodies in rabbit serum samples were well correlated with their bactericidal activities (Geometric mean titer, GMT) following vaccination.Moreover, the dynamic changes of GMC and GMT of the same serotype-specific antibody remained consistent as time went by.Conclusion Rabbit model can be used to analyze the immunogenicity of PCV13 vaccine with quantitative ELISA and OPA, which indicates that it is a suitable animal model for evaluating immunogenicity of pneumococcal conjugate vaccine.