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1.
PLoS Med ; 21(6): e1004375, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829821

RESUMO

BACKGROUND: In Australian remote communities, First Nations children with otitis media (OM)-related hearing loss are disproportionately at risk of developmental delay and poor school performance, compared to those with normal hearing. Our objective was to compare OM-related hearing loss in children randomised to one of 2 pneumococcal conjugate vaccine (PCV) formulations. METHODS AND FINDINGS: In 2 sequential parallel, open-label, randomised controlled trials (the PREVIX trials), eligible infants were first allocated 1:1:1 at age 28 to 38 days to standard or mixed PCV schedules, then at age 12 months to PCV13 (13-valent pneumococcal conjugate vaccine, +P) or PHiD-CV10 (10-valent pneumococcal Haemophilus influenzae protein D conjugate vaccine, +S) (1:1). Here, we report prevalence and level of hearing loss outcomes in the +P and +S groups at 6-monthly scheduled assessments from age 12 to 36 months. From March 2013 to September 2018, 261 infants were enrolled and 461 hearing assessments were performed. Prevalence of hearing loss was 78% (25/32) in the +P group and 71% (20/28) in the +S group at baseline, declining to 52% (28/54) in the +P groups and 56% (33/59) in the +S group at age 36 months. At primary endpoint age 18 months, prevalence of moderate (disabling) hearing loss was 21% (9/42) in the +P group and 41% (20/49) in the +S group (difference -19%; (95% confidence interval (CI) [-38, -1], p = 0.07) and prevalence of no hearing loss was 36% (15/42) in the +P group and 16% (8/49) in the +S group (difference 19%; (95% CI [2, 37], p = 0.05). At subsequent time points, prevalence of moderate hearing loss remained lower in the +P group: differences -3%; (95% CI [-23, 18], p = 1.00 at age 24 months), -12%; (95% CI [-30, 6], p = 0.29 at age 30 months), and -9%; (95% CI [-23, 5], p = 0.25 at age 36 months). A major limitation was the small sample size, hence low power to reach statistical significance, thereby reducing confidence in the effect size. CONCLUSIONS: In this study, we observed a high prevalence and persistence of moderate (disabling) hearing loss throughout early childhood. We found a lower prevalence of moderate hearing loss and correspondingly higher prevalence of no hearing loss in the +P group, which may have substantial benefits for high-risk children, their families, and society, but warrant further investigation. TRIAL REGISTRATION: ClinicalTrials.gov NCT01735084 and NCT01174849.


Assuntos
Perda Auditiva , Otite Média , Vacinas Pneumocócicas , Humanos , Lactente , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/uso terapêutico , Perda Auditiva/epidemiologia , Austrália/epidemiologia , Pré-Escolar , Feminino , Masculino , Otite Média/epidemiologia , Otite Média/prevenção & controle , Prevalência , Vacinas Conjugadas/administração & dosagem , Infecções Pneumocócicas/prevenção & controle , Infecções Pneumocócicas/epidemiologia , Esquemas de Imunização
2.
PLoS Biol ; 18(10): e3000878, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33091022

RESUMO

Predicting how pathogen populations will change over time is challenging. Such has been the case with Streptococcus pneumoniae, an important human pathogen, and the pneumococcal conjugate vaccines (PCVs), which target only a fraction of the strains in the population. Here, we use the frequencies of accessory genes to predict changes in the pneumococcal population after vaccination, hypothesizing that these frequencies reflect negative frequency-dependent selection (NFDS) on the gene products. We find that the standardized predicted fitness of a strain, estimated by an NFDS-based model at the time the vaccine is introduced, enables us to predict whether the strain increases or decreases in prevalence following vaccination. Further, we are able to forecast the equilibrium post-vaccine population composition and assess the invasion capacity of emerging lineages. Overall, we provide a method for predicting the impact of an intervention on pneumococcal populations with potential application to other bacterial pathogens in which NFDS is a driving force.


Assuntos
Evolução Molecular Direcionada , Streptococcus pneumoniae/fisiologia , Simulação por Computador , Modelos Biológicos , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia
3.
Respir Res ; 23(1): 198, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915495

RESUMO

BACKGROUND: Bangladesh introduced the 10-valent pneumococcal conjugate vaccine (PCV10) for children aged < 1 year in March 2015. Previous vaccine effectiveness (VE) studies for pneumonia have used invasive pneumococcal disease or chest X-rays. None have used ultrasound. We sought to determine the VE of PCV10 against sonographically-confirmed pneumonia in three subdistrict health complexes in Bangladesh. METHODS: We conducted a matched case-control study between July 2015 and September 2017 in three subdistricts of Sylhet, Bangladesh. Cases were vaccine-eligible children aged 3-35 months with sonographically-confirmed pneumonia, who were matched with two types of controls by age, sex, week of diagnosis, subdistrict health complex (clinic controls) or distance from subdistrict health complex (community controls) and had an illness unlikely due to Streptococcus pneumoniae (clinic controls) or were healthy (community controls). VE was measured using multivariable conditional logistic regression. RESULTS: We evaluated 8926 children (average age 13.3 months, 58% boys) with clinical pneumonia by ultrasound; 2470 had pneumonia with consolidations ≥ 1 cm; 1893 pneumonia cases were matched with 4238 clinic controls; and 1832 were matched with 3636 community controls. VE increased with the threshold used for consolidation size on ultrasound: the adjusted VE of ≥ 2 doses vs. non-recipients of PCV10 against pneumonia increased from 15.8% (95% CI 1.6-28.0%) for consolidations ≥ 1 cm to 29.6% (12.8-43.2%) for consolidations ≥ 1.5 cm using clinic controls and from 2.7% (- 14.2-17.2%) to 23.5% (4.4-38.8%) using community controls, respectively. CONCLUSIONS: PCV10 was effective at reducing sonographically-confirmed pneumonia in children aged 3-35 months of age when compared to unvaccinated children. VE increased with the threshold used for consolidation size on ultrasound in clinic and community controls alike. This study provides evidence that lung ultrasound is a useful alternative to chest X-ray for case-control studies evaluating the effectiveness of vaccines against pneumonia.


Assuntos
Pneumonia Pneumocócica , Pneumonia , Bangladesh/epidemiologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Lactente , Masculino , Vacinas Pneumocócicas , Pneumonia Pneumocócica/diagnóstico por imagem , Pneumonia Pneumocócica/prevenção & controle
4.
Health Promot Int ; 37(5)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36287519

RESUMO

In 2017, to reduce the burden of measles and rubella, a nation-wide measles-rubella campaign was launched in India. Despite detailed planning efforts that involved many stakeholders, vaccine refusal arose in several communities during the campaign. As strategic health communication and promotion is critical in any vaccine campaign, we sought to document lessons learned from the 2017 MR campaign from a strategic health communication and promotion perspective to capture lessons learned. To inform future campaigns, we conducted in-depth interviews through a perspective that is not usually captured, that of government and civil society stakeholders that had experience in vaccine campaign implementation (n = 21). We interviewed stakeholders at the national level and within three states that had diverse experiences with the campaign. Three key themes related to strategic health communication and promotion emerged: the importance of sensitizing communities at all levels through relevant and timely information about the vaccine and the vaccine campaign, leveraging key influencers to deliver tailored messaging about the importance of vaccines and mitigating vaccine misinformation rapidly. Our study findings have important implications for health communication and promotion research related to vaccine campaigns. The field must continue to enhance vaccine campaign efforts by identifying important health communication and promotion factors, including the importance of sensitization, trusted messengers that use tailored messaging and mitigating misinformation, as vaccine campaigns are crucial in improving vaccine acceptance.


Measles and rubella are diseases that cause sickness and death. Both are preventable as there are safe and effective vaccines available. Measles and rubella are significant in India. These vaccines are generally delivered to the public through vaccine campaigns. A measles­rubella vaccine campaign was implemented in 2017. In this study, we interviewed 21 government and civil society stakeholders that are involved in vaccine campaigns in India to capture lessons learned. We were interested in understanding how vaccine campaigns could be improved through health communication and promotion efforts. Stakeholders suggested to use trusted community members to inform people about the vaccine campaign, and that it was important for trusted community leaders to dispel rumors about vaccines quickly. To increase vaccine acceptance, it is critical that health communication and promotion efforts target concerns that people may have about the vaccine as well as the vaccine campaign.


Assuntos
Sarampo , Rubéola (Sarampo Alemão) , Humanos , Vacina contra Rubéola , Vacina contra Sarampo , Rubéola (Sarampo Alemão)/prevenção & controle , Sarampo/prevenção & controle , Comunicação , Tomada de Decisões , Vacinação
5.
BMC Public Health ; 21(1): 841, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933038

RESUMO

BACKGROUND: India has made substantial progress in improving child health in recent years. However, the country continues to account for a large number of vaccine preventable child deaths. We estimated wealth-related full immunization inequalities in India. We also calculated the degree to which predisposing, reinforcing, and enabling factors contribute to these inequalities. METHODS: We used data from the two rounds of a large nationally representative survey done in all states in India in 2005-06 (n = 9582) and 2015-16 (n = 49,284). Full immunization status was defined as three doses of diphtheria-tetanus-pertussis vaccine, three doses of polio vaccine, one dose of Bacillus Calmette-Guérin vaccine, and one dose of measles vaccine in children 12-23 months. We compared full immunization coverage by wealth quintiles using descriptive statistics. We calculated concentration indices for full immunization coverage at the national and state levels. Using predisposing, reinforcing, and enabling factors associated with full immunization status identified from the literature, we applied a generalized linear model (GLM) framework with a binomial distribution and an identity link to decompose the concentration index. RESULTS: National full immunization coverage increased from 43.65% in 2005-06 to 62.46% in 2015-16. Overall, full immunization coverage in both 2005-06 and 2015-16 in all states was lowest in children from poorer households and improved with increasing socioeconomic status. The national concentration index decreased from 0.36 to 0.13 between the two study periods, indicating a reduction in poor-rich inequality. Similar reductions were observed for most states, except in states where inequalities were already minimal (i.e., Tamil Nadu) and in some northeastern states (i.e., Meghalaya and Manipur). In 2005-06, the contributors to wealth-related full immunization inequality were antenatal care, maternal education, and socioeconomic status. The same factors contributed to full immunization inequality in 2015-16 in addition to difficulty reaching a health facility. CONCLUSIONS: Immunization coverage and wealth-related equality have improved nationally and in most states over the last decade in India. Targeted, context-specific interventions could help address overall wealth-related full immunization inequalities. Intensified government efforts could help in this regard, particularly in high-focus states where child mortality remains high.


Assuntos
Cobertura Vacinal , Vacinação , Criança , Feminino , Humanos , Imunização , Programas de Imunização , Índia , Lactente , Gravidez , Fatores Socioeconômicos
6.
BMC Pediatr ; 21(1): 117, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685411

RESUMO

BACKGROUND: Aboriginal children living in Australian remote communities are at high risk of early and persistent otitis media, hearing loss, and social disadvantage. Streptococcus pneumoniae and non-typeable Haemophilus influenzae (NTHi) are the primary pathogens. We compared otitis media outcomes in infants randomised to either a combination of Synflorix™ (PHiD-CV10, with protein D of NTHi) and Prevenar13™ (PCV13, with 3, 6A, and 19A), with recommended schedules for each vaccine alone. We previously reported superior broader overall immunogenicity of the combination schedule at 7 months, and early superiority of PHiD-CV10 compared to PCV13 at 4 months. METHODS: In an open-label superiority trial, we randomised (1:1:1) Aboriginal infants at 28 to 38 days of age, to either Prevenar13™ (P) at 2-4-6 months (_PPP), Synflorix™ (S) at 2-4-6 months (_SSS), or Synflorix™ at 1-2-4 months plus Prevenar13™ at 6 months (SSSP). Ears were assessed using tympanometry at 1 and 2 months, combined with otoscopy at 4, 6, and 7 months. A worst ear diagnosis was made for each child visit according to a severity hierarchy of normal, otitis media with effusion (OME), acute otitis media without perforation (AOMwoP), AOM with perforation (AOMwiP), and chronic suppurative otitis media (CSOM). RESULTS: Between September 2011 and September 2017, 425 infants were allocated to _PPP(143), _SSS(141) or SSSP(141). Ear assessments were successful in 96% scheduled visits. At 7 months prevalence of any OM was 91, 86, and 90% in the _PPP, _SSS, and SSSP groups, respectively. There were no significant differences in prevalence of any form of otitis media between vaccine groups at any age. Combined group prevalence of any OM was 43, 57, 82, 87, and 89% at 1, 2, 4, 6, and 7 months of age, respectively. Of 388 infants with ear assessments at 4, 6 and 7 months, 277 (71.4%) had OM that met criteria for specialist referral; rAOM, pOME, or CSOM. CONCLUSIONS: Despite superior broader overall immunogenicity of the combination schedule at 7 months, and early superiority of PHiD-CV10 compared to PCV13 at 4 months, there were no significant differences in prevalence of otitis media nor healthy ears throughout the first months of life. TRIAL REGISTRATION: ACTRN12610000544077 registered 06/07/2010 and ClinicalTrials.gov NCT01174849 registered 04/08/2010.


Assuntos
Otite Média , Infecções Pneumocócicas , Austrália , Criança , Haemophilus influenzae , Humanos , Lactente , Otite Média/prevenção & controle , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Vacinas Conjugadas
7.
PLoS Pathog ; 14(4): e1006966, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29617440

RESUMO

In the United States, the introduction of the heptavalent pneumococcal conjugate vaccine (PCV) largely eliminated vaccine serotypes (VT); non-vaccine serotypes (NVT) subsequently increased in carriage and disease. Vaccination also disrupts the composition of the pneumococcal pangenome, which includes mobile genetic elements and polymorphic non-capsular antigens important for virulence, transmission, and pneumococcal ecology. Antigenic proteins are of interest for future vaccines; yet, little is known about how the they are affected by PCV use. To investigate the evolutionary impact of vaccination, we assessed recombination, evolution, and pathogen demographic history of 937 pneumococci collected from 1998-2012 among Navajo and White Mountain Apache Native American communities. We analyzed changes in the pneumococcal pangenome, focusing on metabolic loci and 19 polymorphic protein antigens. We found the impact of PCV on the pneumococcal population could be observed in reduced diversity, a smaller pangenome, and changing frequencies of accessory clusters of orthologous groups (COGs). Post-PCV7, diversity rebounded through clonal expansion of NVT lineages and inferred in-migration of two previously unobserved lineages. Accessory COGs frequencies trended toward pre-PCV7 values with increasing time since vaccine introduction. Contemporary frequencies of protein antigen variants are better predicted by pre-PCV7 values (1998-2000) than the preceding period (2006-2008), suggesting balancing selection may have acted in maintaining variant frequencies in this population. Overall, we present the largest genomic analysis of pneumococcal carriage in the United States to date, which includes a snapshot of a true vaccine-naïve community prior to the introduction of PCV7. These data improve our understanding of pneumococcal evolution and emphasize the need to consider pangenome composition when inferring the impact of vaccination and developing future protein-based pneumococcal vaccines.


Assuntos
Genoma Bacteriano , Vacina Pneumocócica Conjugada Heptavalente/administração & dosagem , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Sorogrupo , Streptococcus pneumoniae/imunologia , Adolescente , Adulto , Idoso , Criança , Genética Populacional , Humanos , Pessoa de Meia-Idade , Nasofaringe/microbiologia , Filogenia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Dinâmica Populacional , Estudos Prospectivos , Sorotipagem , Streptococcus pneumoniae/genética , Vacinação , Adulto Jovem
8.
Am J Epidemiol ; 188(12): 2110-2119, 2019 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-31509184

RESUMO

Culture-based methods for detecting Streptococcus pneumoniae in the nasopharynx lack sensitivity. In this study, we aimed to compare the performance of culture and molecular methods in detecting pneumococcus in the nasopharynx of healthy individuals and to evaluate the associations of age and colonization density with detection. Between 2010 and 2012, nasopharyngeal specimens were collected from healthy individuals living on Navajo Nation and White Mountain Apache Tribal lands in the United States. Pneumococci were detected by means of broth-enrichment culture and autolysin-encoding gene (lytA) quantitative polymerase chain reaction (qPCR). Among 982 persons evaluated (median age, 18.7 years; 47% male), 35% were culture-positive and an additional 27% were qPCR-positive. Agreement between culture and qPCR was 70.9% but was higher among children (age <18 years) (75.9%-84.4%) than among adults (age ≥18 years) (61.0%-74.6%). The mean density of colonization was lower for culture-negative samples (3.14 log10 copies/mL) than for culture-positive samples (5.02 log10 copies/mL), overall and for all age groups. The percent culture-positive increased with increasing density, exceeding 80% at densities of ≥10,000 copies/mL. Mean colonization density decreased with age. Use of qPCR improved detection of pneumococcus in the nasopharynx of healthy individuals. This finding was most notable among adults, probably because of improved detection of low-density colonization.


Assuntos
Técnicas de Cultura , Nasofaringe/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
9.
BMC Infect Dis ; 19(1): 605, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291902

RESUMO

BACKGROUND: Streptococcus pneumoniae is a major cause of pneumonia, meningitis, and other serious infections among children in India. India introduced the 13-valent pneumococcal conjugate vaccine (PCV) in several states in 2017, and is expected to expand to nationwide coverage in the near future. To establish a baseline for measuring the impact of PCV in India, we assessed overall and serotype-specific nasopharyngeal carriage in two pediatric populations. METHODS: A cross-sectional study was conducted in Palwal District, Haryana, from December 2016 to July 2017, prior to vaccine introduction. Children 2-59 months of age with clinical pneumonia seeking healthcare and those in the community with no clear illness were targeted for enrollment. A nasopharyngeal swab was collected and tested for pneumococcus using conventional culture and sequential multiplex PCR. Isolates were tested for antimicrobial resistance using an E test. Children were considered colonized if pneumococcus was isolated by culture or PCR. The prevalence of pneumococcal and serotype-specific colonization was compared between groups of children using log-binomial regression. RESULTS: Among 601 children enrolled, 91 had clinical pneumonia and 510 were community children. The proportion colonized with S. pneumoniae was 74.7 and 54.5% among children with clinical pneumonia and community children, respectively (adjusted prevalence ratio: 1.38; 95% confidence interval: 1.19, 1.60). The prevalence of PCV13 vaccine-type colonization was similar between children with clinical pneumonia (31.9%) and community children (28.0%; p = 0.46). The most common colonizing serotypes were 6A, 6B, 14, 19A, 19F, and 23F, all of which are included in the PCV13 vaccine product. Antimicrobial resistance to at least one drug was similar between isolates from children with clinical pneumonia (66.1%) and community children (61.5%; p = 0.49); while resistance to at least two drugs was more common among isolates from children with clinical pneumonia (25.8% vs. 16.4%; p = 0.08). Resistance for all drugs was consistently higher for PCV13 vaccine-type serotypes compared to non-vaccine serotypes in both groups. CONCLUSION: This study provides baseline information on the prevalence of serotype-specific pneumococcal colonization among children prior to the introduction of PCV in India. Our results suggest a role for pneumococcal vaccines in reducing pneumococcal colonization and antimicrobial resistant isolates circulating in India.


Assuntos
Portador Sadio/microbiologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Antibacterianos/farmacologia , Portador Sadio/epidemiologia , Pré-Escolar , Estudos Transversais , Farmacorresistência Bacteriana , Feminino , Humanos , Índia/epidemiologia , Lactente , Masculino , Testes de Sensibilidade Microbiana , Nasofaringe/microbiologia , Infecções Pneumocócicas/epidemiologia , Prevalência , Sorogrupo , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/genética , Vacinas Conjugadas
10.
J Trop Pediatr ; 64(2): 110-117, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575379

RESUMO

Objective: To evaluate the effect of zinc as an adjuvant therapy in radiologically confirmed pneumonia in children 2-24 months of age. Patients and Methods: We analyzed data of 212 children with pneumonia for whom chest X-ray films were available at enrollment and at least two radiologists agreed on the diagnosis of pneumonia. We compared the time to recovery in the two groups (n = 121, zinc group and n = 91, placebo group) using a Cox proportional hazards regression model. Results: Time to recovery was similar in both groups [median interquartile range: zinc, 84 h (64, 140 h); placebo, 85 h (65, 140 h)]. The absolute risk reduction for treatment failure was 5.2% (95% confidence interval: -4.8, 15.1) with zinc supplementation. Conclusion: There was no significant beneficial effect of zinc on the duration of recovery or risk of treatment failure in children with radiologically confirmed pneumonia.


Assuntos
Pneumonia/tratamento farmacológico , Zinco/uso terapêutico , Suplementos Nutricionais/efeitos adversos , Suplementos Nutricionais/estatística & dados numéricos , Método Duplo-Cego , Feminino , Humanos , Lactente , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pneumonia/diagnóstico por imagem , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
12.
Trop Med Int Health ; 20(10): 1320-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26083963

RESUMO

OBJECTIVE: Stunting affects 26.7% of children worldwide, and little is known about its effects on the outcomes of childhood pneumonia. We evaluated the effect of stunting on the outcomes of pneumonia among children enrolled in two large clinical trials. METHODS: We analysed data from two WHO and USAID-sponsored inpatient treatment trials, the Severe Pneumonia Evaluation Antimicrobial Research study (n = 958) and the Amoxicillin Penicillin Pneumonia International Study (n = 1702), which enrolled children aged 2-59 months across 16 sites in LMICs. We assessed the effect of stunting (height-for-age Z score < -2) on treatment outcome and time to resolution of hypoxaemic pneumonia. RESULTS: Among 2542 (96%) children with valid data for height, 28% were stunted and 12.8% failed treatment by 5 days. The failure rate among stunted patients was 16.0% vs. 11.5% among non-stunted patients [unadjusted RR = 1.24 (95% CI 1.08, 1.41); adjusted RR = 1.28 (95% CI 1.10, 1.48)]. An inverse relationship was observed between height and failure rates, even among non-stunted children. Among 845 patients with hypoxaemic pneumonia, stunting was associated with a lower probability of normalisation of respiratory rate [HR = 0.63 (95% CI 0.52, 0.75)] and oxygen saturation [HR = 0.74 (95% CI 0.61, 0.89)]. CONCLUSIONS: Stunting increases the risk of treatment failure and is associated with a longer course of recovery in children with pneumonia. Strategies to decrease stunting may decrease the burden of adverse outcomes in childhood pneumonia in low-resource settings.


Assuntos
Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Transtornos do Crescimento/epidemiologia , Penicilinas/administração & dosagem , Pneumonia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pneumonia/tratamento farmacológico , Pneumonia/epidemiologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
13.
Clin Infect Dis ; 58(2): 188-94, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24190895

RESUMO

BACKGROUND: Winter-seasonal epidemics of pneumococcal disease provide an opportunity to understand the drivers of incidence. We sought to determine whether seasonality of invasive pneumococcal disease is caused by increased nasopharyngeal transmission of the bacteria or increased susceptibility to invasive infections driven by cocirculating winter respiratory viruses. METHODS: We analyzed pneumococcal carriage and invasive disease data collected from children <7 years old in the Navajo/White Mountain Apache populations between 1996 and 2012. Regression models were used to quantify seasonal variations in carriage prevalence, carriage density, and disease incidence. We also fit a multivariate model to determine the contribution of carriage prevalence and RSV activity to pneumococcal disease incidence while controlling for shared seasonal factors. RESULTS: The seasonal patterns of invasive pneumococcal disease epidemics varied significantly by clinical presentation: bacteremic pneumococcal pneumonia incidence peaked in late winter, whereas invasive nonpneumonia pneumococcal incidence peaked in autumn. Pneumococcal carriage prevalence and density also varied seasonally, with peak prevalence occurring in late autumn. In a multivariate model, RSV activity was associated with significant increases in bacteremic pneumonia cases (attributable percentage, 15.5%; 95% confidence interval [CI], 1.8%-26.1%) but was not associated with invasive nonpneumonia infections (8.0%; 95% CI, -4.8% to 19.3%). In contrast, seasonal variations in carriage prevalence were associated with significant increases in invasive nonpneumonia infections (31.4%; 95% CI, 8.8%-51.4%) but not with bacteremic pneumonia. CONCLUSIONS: The seasonality of invasive pneumococcal pneumonia could be due to increased susceptibility to invasive infection triggered by viral pathogens, whereas seasonality of other invasive pneumococcal infections might be primarily driven by increased nasopharyngeal transmission of the bacteria.


Assuntos
Portador Sadio/epidemiologia , Infecções Pneumocócicas/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Estações do Ano , Adulto , Criança , Pré-Escolar , Humanos , Incidência , Lactente , Infecções por Vírus Respiratório Sincicial/complicações
14.
Respir Res ; 15: 50, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24758612

RESUMO

BACKGROUND: Guidelines do not currently recommend the use of lung ultrasound (LUS) as an alternative to chest X-ray (CXR) or chest computerized tomography (CT) scan for the diagnosis of pneumonia. We conducted a meta-analysis to summarize existing evidence of the diagnostic accuracy of LUS for pneumonia in adults. METHODS: We conducted a systematic search of published studies comparing the diagnostic accuracy of LUS against a referent CXR or chest CT scan and/or clinical criteria for pneumonia in adults aged ≥18 years. Eligible studies were required to have a CXR and/or chest CT scan at the time of evaluation. We manually extracted descriptive and quantitative information from eligible studies, and calculated pooled sensitivity and specificity using the Mantel-Haenszel method and pooled positive and negative likelihood ratios (LR) using the DerSimonian-Laird method. We assessed for heterogeneity using the Q and I2 statistics. RESULTS: Our initial search strategy yielded 2726 articles, of which 45 (1.7%) were manually selected for review and 10 (0.4%) were eligible for analyses. These 10 studies provided a combined sample size of 1172 participants. Six studies enrolled adult patients who were either hospitalized or admitted to Emergency Departments with suspicion of pneumonia and 4 studies enrolled critically-ill adult patients. LUS was performed by highly-skilled sonographers in seven studies, by trained physicians in two, and one did not mention level of training. All studies were conducted in high-income settings. LUS took a maximum of 13 minutes to conduct. Nine studies used a 3.5-5 MHz micro-convex transducer and one used a 5-9 MHz convex probe. Pooled sensitivity and specificity for the diagnosis of pneumonia using LUS were 94% (95% CI, 92%-96%) and 96% (94%-97%), respectively; pooled positive and negative LRs were 16.8 (7.7-37.0) and 0.07 (0.05-0.10), respectively; and, the area-under-the-ROC curve was 0.99 (0.98-0.99). CONCLUSIONS: Our meta-analysis supports that LUS, when conducted by highly-skilled sonographers, performs well for the diagnosis of pneumonia. General practitioners and Emergency Medicine physicians should be encouraged to learn LUS since it appears to be an established diagnostic tool in the hands of experienced physicians.


Assuntos
Pulmão/diagnóstico por imagem , Pneumonia/diagnóstico por imagem , Adulto , Ensaios Clínicos como Assunto , Humanos , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Ultrassonografia
15.
J Trop Pediatr ; 60(4): 287-91, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24567310

RESUMO

Haemophilus influenzae type B (Hib) vaccine, pneumococcal conjugate vaccine (PCV) and rotavirus (RV) vaccine are available in the private market in India, but, except for Hib in eight states, are not included in India's Universal Immunization Program (UIP). Pediatricians were surveyed about administering non-UIP vaccines. Most give these vaccines to some of their patients (73-83%, depending on vaccine), but few give them to all patients (7-18%). High cost was the most frequently cited barrier (93-96%). Only 10-12% of respondents had concerns about the efficacy of PCV or RV vaccine, and concerns about Hib vaccine efficacy or any vaccine safety issues were rare (1-3%). Practice varied by type of healthcare facility, with pediatricians at government hospitals least likely to administer non-UIP vaccines. Support for the inclusion of all three in the UIP was high (83-95%). Including Hib vaccine, PCV and RV vaccine in India's UIP would be supported by pediatricians and help eliminate the current barrier of high cost of these immunizations.


Assuntos
Infecções por Haemophilus/prevenção & controle , Vacinas Anti-Haemophilus/administração & dosagem , Vacinas Anti-Haemophilus/economia , Programas de Imunização/economia , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Atitude do Pessoal de Saúde , Pesquisas sobre Atenção à Saúde , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/economia , Vacinas contra Rotavirus/administração & dosagem , Vacinas contra Rotavirus/economia , Vacinação/economia , Vacinação/estatística & dados numéricos
16.
J Infect Dis ; 208(2): 284-94, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23596320

RESUMO

BACKGROUND: Identifying an immunological correlate of protection for rotavirus vaccines (Rotarix [RV1] and RotaTeq [RV5]) would substantially facilitate testing of interventions for improving efficacy in developing countries and evaluating additional candidate rotavirus vaccines. METHODS: We accessed PubMed and ClinicalTrials.gov to identify immunogenicity and efficacy trials for RV1 and RV5 to correlate anti-rotavirus serum immunoglobulin A (IgA) antibody titers vs efficacy in regions stratified by all-cause under-5 mortality rates (u5MR). We established a cutoff point for IgA geometric mean concentration or titer (GMC) that predicted lower efficacy and calculated pooled vaccine efficacy among countries with high vs low IgA titers. FINDINGS: We observed an inverse correlation between u5MR and IgA titers for RV1 (r(2) = 0.72; P < .001 and RV5 (r(2) = 0.66; P < .001) and between efficacy and IgA titers for both vaccines (r(2) = 0.56; P = .005). Postimmunization anti-rotavirus IgA GMC <90 were associated with decline in vaccine efficacy. Efficacy during first 2 years of life was significantly lower among countries with IgA GMC < 90 (44%; 95% confidence interval [CI], 30-55) compared to countries with GMC > 90 (85%; 95% CI, 82-88). INTERPRETATION: We observed a significant correlation between IgA titers and rotavirus vaccine efficacy and hypothesize that a critical level of IgA antibody titer is associated with a sufficient level of sustained protection after rotavirus vaccination.


Assuntos
Formação de Anticorpos/imunologia , Imunoglobulina A/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Rotavirus/imunologia , Anticorpos Antivirais/sangue , Humanos , Imunoglobulina A/sangue , Vacinas Atenuadas/imunologia
17.
Vaccine ; 42(1): 8-16, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042696

RESUMO

Despite the 2009 World Health Organization recommendation that all countries introduce rotavirus vaccines (RVV) into their national immunization programs, just 81 countries had introduced RVV by the end of 2015, leaving millions of children at risk for rotavirus morbidity and mortality. In response, the Rotavirus Accelerated Vaccine Introduction Network (RAVIN) was established in 2016 to provide support to eight Gavi-eligible countries that had yet to make an RVV introduction decision and/or had requested technical assistance with RVV preparations: Afghanistan, Bangladesh, Benin, Cambodia, Democratic Republic of Congo, Lao People's Democratic Republic, Myanmar, and Nepal. During 2016-2020, RAVIN worked with country governments and partners to support evidence-based immunization decision-making, RVV introduction preparation and implementation, and multilateral coordination. By the September 2020 program close-out, five of the eight RAVIN focus countries successfully introduced RVV into their routine childhood immunization programs. We report on the RAVIN approach, describe how the project responded collectively to an evolving RVV product landscape, synthesize common characteristics of the RAVIN country experiences, highlight key lessons learned, and outline the unfinished agenda to inform future new vaccine introduction efforts by countries and global partners.


Assuntos
Programas de Imunização , Infecções por Rotavirus , Vacinas contra Rotavirus , Criança , Humanos , Países em Desenvolvimento , Rotavirus , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Vacinação , Organização Mundial da Saúde
18.
Microb Genom ; 10(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38498591

RESUMO

Background. Despite use of highly effective conjugate vaccines, invasive pneumococcal disease (IPD) remains a leading cause of morbidity and mortality and disproportionately affects Indigenous populations. Although included in the 13-valent pneumococcal conjugate vaccine (PCV13), which was introduced in 2010, serotype 3 continues to cause disease among Indigenous communities in the Southwest USA. In the Navajo Nation, serotype 3 IPD incidence increased among adults (3.8/100 000 in 2001-2009 and 6.2/100 000 in 2011-2019); in children the disease persisted although the rates dropped from 5.8/100 000 to 2.3/100 000.Methods. We analysed the genomic epidemiology of serotype 3 isolates collected from 129 adults and 63 children with pneumococcal carriage (n=61) or IPD (n=131) from 2001 to 2018 of the Navajo Nation. Using whole-genome sequencing data, we determined clade membership and assessed changes in serotype 3 population structure over time.Results. The serotype 3 population structure was characterized by three dominant subpopulations: clade II (n=90, 46.9 %) and clade Iα (n=59, 30.7 %), which fall into Clonal Complex (CC) 180, and a non-CC180 clade (n=43, 22.4 %). The proportion of clade II-associated IPD cases increased significantly from 2001 to 2010 to 2011-2018 among adults (23.1-71.8 %; P<0.001) but not in children (27.3-33.3 %; P=0.84). Over the same period, the proportion of clade II-associated carriage increased; this was statistically significant among children (23.3-52.6 %; P=0.04) but not adults (0-50.0 %, P=0.08).Conclusions. In this setting with persistent serotype 3 IPD and carriage, clade II has increased since 2010. Genomic changes may be contributing to the observed trends in serotype 3 carriage and disease over time.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Criança , Adulto , Humanos , Vacinas Conjugadas , Sorogrupo , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Incidência
19.
Clin Infect Dis ; 56(4): 548-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23271788

RESUMO

The recent introduction of a rotavirus vaccine program in Mexico to control rotavirus disease, a common killer of children worldwide, has dramatically reduced the number of Mexican children dying and being hospitalized because of diarrhea. The successful introduction of a rotavirus vaccine program was preceded by several decades of focused research efforts to document the burden of disease and to generate the knowledge base to develop and deploy a vaccine. The postlicensure experience from Mexico demonstrates that evaluating the impact and safety of the vaccination program is vitally necessary for sustaining it. All in all, the immensely successful Mexico experience with control of rotavirus disease, if copied, could yield tremendously favorable results for children and parents worldwide.


Assuntos
Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Rotavirus/imunologia , Pré-Escolar , Humanos , Programas de Imunização/métodos , Lactente , México , Infecções por Rotavirus/imunologia , Vacinação/métodos , Vacinas Atenuadas/administração & dosagem
20.
Lancet ; 379(9820): 1022-8, 2012 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-22322124

RESUMO

BACKGROUND: Up to half of neonatal deaths in high mortality settings are due to infections, many of which can originate through the freshly cut umbilical cord stump. We aimed to assess the effectiveness of two cord-cleansing regimens with the promotion of dry cord care in the prevention of neonatal mortality. DESIGN: We did a community-based, parallel cluster-randomised trial in Sylhet, Bangladesh. We divided the study area into 133 clusters, which were randomly assigned to one of the two chlorhexidine cleansing regimens (single cleansing as soon as possible after birth; daily cleansing for 7 days after birth) or promotion of dry cord care. Randomisation was done by use of a computer-generated sequence, stratified by cluster-specific participation in a previous trial. All livebirths were eligible; those visited within 7 days by a local female village health worker trained to deliver the cord care intervention were enrolled. We did not mask study workers and participants to the study interventions. Our primary outcome was neonatal mortality (within 28 days of birth) per 1000 livebirths, which we analysed on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, number NCT00434408. RESULTS: Between June, 2007, and September, 2009, we enrolled 29 760 newborn babies (10 329, 9423, and 10 008 in the multiple-cleansing, single-cleansing, and dry cord care groups, respectively). Neonatal mortality was lower in the single-cleansing group (22·5 per 1000 livebirths) than it was in the dry cord care group (28·3 per 1000 livebirths; relative risk [RR] 0·80 [95% CI] 0·65-0·98). Neonatal mortality in the multiple-cleansing group (26·6 per 1000 livebirths) was not statistically significantly lower than it was in the dry cord care group (RR 0·94 [0·78-1·14]). Compared with the dry cord care group, we recorded a statistically significant reduction in the occurrence of severe cord infection (redness with pus) in the multiple-cleansing group (risk per 1000 livebirths=4·2 vs risk per 1000 livebirths=1·2; RR 0·35 [0·15-0·81]) but not in the single-cleansing group (risk per 1000 livebirths=3·3; RR 0·77 [0·40-1·48]). INTERPRETATION: Chlorhexidine cleansing of a neonate's umbilical cord can save lives, but further studies are needed to establish the best frequency with which to deliver the intervention. FUNDING: United States Agency for International Development and Save the Children's Saving Newborn Lives program, through a grant from the Bill & Melinda Gates Foundation.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Clorexidina/administração & dosagem , Agentes Comunitários de Saúde , Sepse/prevenção & controle , Cordão Umbilical/microbiologia , Adulto , Bangladesh/epidemiologia , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Gravidez , População Rural
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