The potential impact of PCV-13, PCV-15 and PCV-20 vaccines in Colombia.

PURPOSE: To provide information about which pneumococcal vaccine could have greater coverage in Colombia. METHODS: This is a retrospective analysis of patients diagnosed with invasive pneumococcal disease (IPD) between 2015 and 2019 in Bogotá, Colombia. We compared the theoretical serotype coverage of the available anti-pneumococcal vaccines (i.e., PCV-10, PCV-10 SII, PCV-13, PCV-15, PCV-20, PCV-21, PCV24, PPSV-23) and the non-vaccine-covered serotypes stratified by age. RESULTS: 690 IPD cases were included. In children ≤5 y/o, of the approved vaccines PCV-20 showed the most theoretical protection (71.3 % [149/209]), while in adults aged 18-64 y/o was PCV-20 (61.8 % [164/265]), and in those ≥65 y/o was PPSV-23 (58.1 % [100/172]) followed by PCV-20 (55.2 % [95/172]). The non-covered serotypes represented one-third of the cohort (33.9 % [234/690]), being 6C (20.5 % [48/234]), 15A (12.8 % [30/234]), and 23A (11.5 % [27/234]) the most prevalent. CONCLUSION: Introducing PCV-20 for children and PCV-20 along with a PPSV-23 booster in adults may reduce IPD frequency in all ages in Colombia. The inclusion of non-covered serotypes is required for future vaccines.

Combined 13-valent pneumococcal conjugate and 23-valent pneumococcal polysaccharide vaccine regimens for adults with systemic lupus erythematosus: Does the sequence of pneumococcal vaccination affect immunogenicity responses? A single-center cohort study in Brazil.

OBJECTIVE: A combination of 13-valent pneumococcal conjugate vaccine (PCV13) and 23-valent pneumococcal polysaccharide vaccine (PPSV23) is currently recommended for adults with systemic lupus erythematosus (SLE). However, data on the immunogenicity elicited by sequential pneumococcal vaccination in this patient population are scarce. In this study, we compared short-term antibody responses to both PCV13/PPSV23 (≥8-week interval) and PPSV23/PCV13 (≥12-month interval) vaccination strategies in pneumococcal vaccine-naive adults with SLE. METHODS: This longitudinal, open-label, quasi-randomized study was performed in a single-center cohort of adults (18 years or older) with SLE. In both vaccination groups, blood samples were collected immediately before administering the first dose of the pneumococcal vaccine (timepoint T0), 4-6 weeks after the priming dose (T1), and 4-6 weeks after the booster dose (T2). We focused on the 12 shared serotypes between PCV13 and PPSV23, and compared the following immunogenicity outcomes between the groups at T2: anti-pneumococcal antibody geometric mean concentration (ApAb GMC), fold increase in ApAb levels (FI-ApAb), overall seroprotection rate, and overall seroconversion rate. The protective level for each pneumococcal serotype was set at 1.3 µg/mL. We used the multi-analyte immunodetection method to determine serum levels of ApAbs. RESULTS: Thirty-four patients with SLE were screened between April 2019 and January 2020, and 16 of them (mean age: 39.4 years, 87.5% female, and 100% on immunosuppressants) had evaluable immunogenicity results at T2. The median time elapsed between the pneumococcal vaccinations was 56 days in the PCV13/PPSV23 group (n = 11 patients) and 16 months in the PPSV23/PCV13 group (n = 5 patients). Priming with PCV13 (PCV13/PPSV23 group), as opposed to PPSV23 (PPSV23/PCV13 group), yielded significantly better results regarding FI-ApAb, overall seroconversion rate, and overall seroprotection rate 4-6 weeks after each pneumococcal vaccination. A trend toward augmented ApAb GMC in the patients who received the PCV13/PPSV23 sequence was also observed. No relevant safety issues were identified with sequential pneumococcal vaccination. CONCLUSION: The PCV13-priming PPSV23-boost strategy in adults with SLE induced greater antibody responses for most immunogenicity outcomes than those elicited by the PPSV23/PCV13 strategy.

Cost-Effectiveness of Pneumococcal Vaccines for Adults Aged 65 Years and Older in Argentina.

OBJECTIVES: In 2017, the Argentine Ministry of Health incorporated a sequential 13-valent pneumococcal conjugate vaccine (PCV13)-23-valent pneumococcal polysaccharide vaccine (PPSV23) regimen for adults aged ≥65 years to reduce pneumococcal disease burden. Cost-effectiveness analysis of PCV13-PPSV23 schedule for adults aged ≥65 years in Argentina was performed compared with PPSV23 only. METHODS: Markov model was developed. Local data were incorporated for costs and disease burden analysis. Vaccine efficacy or effectiveness was obtained from a systematic review adjusted to current local vaccine serotype circulation and vaccines coverage. A total of 3 scenarios were evaluated: main scenario according to published literature of pneumonia incidence, epidemiologic surveillance scenario based on Argentine Ministry of Health data, and an alternative scenario assuming a 50% hypothetical pneumonia incidence reduction resulting from herd immunity induced by childhood vaccination. Sensitivity analyses were done. RESULTS: Sequential PCV13-PPSV23 schedule showed cost-savings results in the main scenario with -$1 667 742.23 saved and 716 life-years gained (LYG). The epidemiologic surveillance scenario showed an incremental cost-effectiveness ratio of $2141.92 per LYG and an alternative scenario with $3740.30 per LYG. Tornado diagram shows widest bars related to adjustment for vaccine-type pneumococcal pneumonia (urine analysis) pneumonia at risk cost and pneumonia incidence rate. Monte Carlo simulation shows that >98% of simulations were cost-saving for the main scenario. CONCLUSIONS: In the main scenario, cost-saving results were obtained considering only reduction of vaccine serotype coverage after the introduction of childhood PCV13 vaccination. In the epidemiologic surveillance and alternative scenarios, assuming a hypothetical incidence reduction, highly cost-effective results were observed.

Constrained Optimization for Pneumococcal Vaccination in Brazil.

OBJECTIVES: To identify the most cost-efficient combination of pneumococcal vaccines in infants and aging adults for a 10-year period in Brazil. METHODS: Constrained optimization (CO) prioritized 9 pneumococcal vaccine regimens according to their gain in quality-adjusted life-years (QALYs) and their related costs over a prespecified time horizon with defined constraints for 2 age groups, infants and aging adults. The analysis starts from the current universal infant vaccination of pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV), 2 primary and 1 booster dose at 2, 4, and 12 months, respectively. Key constraints are the fixed annual vaccine budget increase and the relative return on investment (ROIR) per regimen, which must be > 1, the reference intervention being the current vaccination strategy in infants and the most cost-efficient one in aging adults. RESULTS: The CO analysis including all the constraints indicates that over 10 years the maximum extra health gain is 126 194 QALYs for an extra budget of $974 million Brazilian reals (ROIR = 1.15). Results could be improved with a higher proportion of the at-risk population in aging adults, less herd effect, and better QALY scores. CONCLUSION: The study shows that with 4 constraints on budget, time horizon, vaccine coverage, and cost efficiency, a CO analysis could identify the most cost-efficient overall pneumococcal vaccination strategy for Brazil, allowing for limited vaccine budget increase while obtaining appropriate health gain.

Influenza and Pneumococcal Vaccination in Non-Infected Cardiometabolic Patients from the Americas during the COVID-19 Pandemic. A Sub-Analysis of the CorCOVID-LATAM Study.

BACKGROUND: Influenza vaccination (IV) and Pneumococcus vaccination (PV) are recommended for patients with cardiometabolic diseases. This study aimed to evaluate the immunization rate of ambulatory cardiometabolic patients during the COVID-19 pandemic in the Americas. METHODS: Electronic surveys were collected from 13 Spanish speaking countries between 15 June and 15 July 2020. RESULTS: 4216 patients were analyzed. Mean age 60 (±15) years and 49% females. Global IV rate was 46.5% and PV 24.6%. Vaccinated patients were older (IV = 63 vs. 58 years; PV = 68 vs. 59, p < 0.01) but without gender difference. Vaccination rates were greater in higher-risk groups (65+, diabetics, heart failure), but not in coronary artery disease patients. In the Southern cone, the rate of IV and PV was approximately double that in the tropical regions of the Americas. In a multivariate model, geographic zone (IV = OR 2.02, PV = OR 2.42, p < 0.001), age (IV = OR 1.023, PV = OR 1.035, p < 0.001), and incomes (IV = OR 1.28, PV = OR 1.58, p < 0.001) were predictors for vaccination. CONCLUSIONS: During the COVID-19 pandemic, ambulatory patients with cardiometabolic diseases from the Americas with no evidence of COVID-19 infection had lower-than-expected rates of IV and PV. Geographic, social, and cultural differences were found, and they should be explored in depth.

Puesta al día en vacunación antineumocócica en adultos / Update on pneumococcal vaccination in adults

La enfermedad invasiva por Streptococcus pneumoniae constituye una importante causa de morbilidad y mortalidad, y es la primera causa de muerte prevenible mediante vacunación en el mundo, no solo en niños sino en todas las edades. Tanto la vacuna polisacárida como la vacuna conjugada antineumocócicas han demostrado reducción de las tasas de enfermedad invasiva en adultos. En los últimos años, a la luz de nueva evidencia disponible, los esquemas de vacunación antineumocócica para esta población han sufrido modificaciones. Este documento ofrece una actualización sobre las recomendaciones de vacunación a través de los fundamentos que han llevado a dicho cambio. (AU)

The Streptococcus pneumoniae invasive disease is a major cause of morbidity and mortality, being the leading cause of vaccine-preventable death in the world, not only in children but in all ages. Both the polysaccharide vaccine and pneumococcal conjugate vaccine have shown reduced rates of invasive disease in adults. In recent years, in light of new evidence available, schedules of pneumococcal vaccination for this population have changed. This document provides an update on vaccine recommendations through the rational that have led to this change. (AU)

Autotransplantation of spleen tissue in children with mansonic schistosomiasis who underwent splenectomy: Evaluation of splenic residual functions

Autotransplantation of spleen tissue is an attempt for maintenance of splenic functions when splenectomy is indicated in children. It minimizes the risks of overwhelming postsplenectomy infection and it has been done in children with severe portal hypertension due to hepatosplenic mansonic schistosomiasis that underwent splenectomy. The purposes of this investigation were to study the morphology of the residual splenic tissue; to evaluate the residual filtration function of this splenosis; and to assess the immune response to polyvalent pneumococcal vaccine of these patients. Twenty-three children with portal hypertension from mansonic schistosomiasis who underwent splenectomy, ligature of the left gastric vein, autotransplantation of spleen tissue into an omental pouch were evaluated for residual splenic parenchyma and functions. Tc-99m sulfur colloid liver-spleen scans were used for detection of splenic nodules. The search for Howell Jolly bodies were used for assessing the filtration function and Enzyme-linked immunosorbent assay was used for measuring the relative rise in titter of specific pneumococcal antibodies. Splenosis was evident in all children; however, in two there were less than five splenic nodules in the greater omentum, which was considered insufficient. Howell-Jolly bodies were found in the peripheral blood only in these two patients with less evident splenosis. The immune response was adequate in 15 patients; it was intermediate in 4 patients and inadequate in 4 patients. Autotransplantation of spleen tissue into an omental pouch is efficient in maintaining the filtration splenic function in more than 90% of the cases and the immune response to pneumococcal vaccination in approximately 65% of the children.

Transplante autólogo de tecido esplênico é uma tentativa de manter as funções esplênicas quando esplenectomia está indicado em crianças. Ele minimiza os riscos de septicemia fulminante após esplenectomia e tem sido feito em crianças com hipertensão porta severa, devido a hepato-esplenomegalia esquistossomótica, que se submeteram à esplenectomia. Os objetivos da presente investigação foram: estudar a morfologia do tecido esplênico residual; avaliar a função de filtração da esplenose; e avaliar a resposta imune à vacinação polivalente contra pneumococos destes pacientes. Vinte e três crianças com hipertensão porta, devido a esquistossomose mansônica, que se submeteram à esplenectomia, ligadura da veia gástrica esquerda, autotransplante de tecido esplênico em bolsa no omento maior foram avaliadas para as funções esplênicas residuais. Cintilografia hepatoesplênica com enxofre coloidal marcado com Tc-99m foi usado para detecção dos nódulos esplênicos. A pesquisa de corpúsculos de Howell Jolly foi usada para avaliar a função de filtração. A avaliação da resposta de anticorpos contra pneumococos foi medida pelo método de Elisa. Esplenose foi evidente em todas as crianças, contudo, em dois, foi identificado menos de cinco nódulos esplênicos no omento maior, a qual foi considerada insuficiente. Corpúsculos de Howell Jolly foram encontrados no sangue periférico somente nesses dois pacientes com esplenose menos evidente. A resposta imune foi adequada em quinze pacientes; foi intermediária em quatro pacientes e inadequada em outros quatro. Transplante autólogo de tecido esplênico em bolsa do omento maior foi considerado eficiente na manutenção da função esplênica em mais de 90% dos pacientes e da resposta imune à vacinação contra pneumococos em aproximadamente 65% das crianças.