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1.
J Urban Health ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578336

RESUMO

This study reviews the impact of eligibility policies in the early rollout of the COVID-19 vaccine on coverage and probable outcomes, with a focus on New York City. We conducted a retrospective ecological study assessing age 65+, area-level income, vaccination coverage, and COVID-19 mortality rates, using linked Census Bureau data and New York City Health administrative data aggregated at the level of modified zip code tabulation areas (MODZCTA). The population for this study was all individuals in 177 MODZCTA in New York City. Population data were obtained from Census Bureau and New York City Health administrative data. The total mortality rate was examined through an ordinary least squares (OLS) regression model, using area-level wealth, the proportion of the population aged 65 and above, and the vaccination rate among this age group as predictors. Low-income areas with high proportions of older people demonstrated lower coverage rates (mean vaccination rate 52.8%; maximum coverage 67.9%) than wealthier areas (mean vaccination rate 74.6%; maximum coverage 99% in the wealthiest quintile) in the first 3 months of vaccine rollout and higher mortality over the year. Despite vaccine shortages, many younger people accessed vaccines ahead of schedule, particularly in high-income areas (mean coverage rate 60% among those 45-64 years in the wealthiest quintile). A vaccine program that prioritized those at greatest risk of COVID-19-associated morbidity and mortality would have prevented more deaths than the strategy that was implemented. When rolling out a new vaccine, policymakers must account for local contexts and conditions of high-risk population groups. If New York had focused limited vaccine supply on low-income areas with high proportions of residents 65 or older, overall mortality might have been lower.

2.
Vaccine X ; 18: 100464, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38495929

RESUMO

Introduction: The GAIA (Global Alignment on Immunisation Safety Assessment in Pregnancy) consortium was established in 2014 with the aim of creating a standardised, globally coordinated approach to monitoring the safety of vaccines administered in pregnancy. The consortium developed twenty-six standardised definitions for classifying obstetric and infant adverse events. This systematic review sought to evaluate the current state of adverse event reporting in maternal vaccine trials following the publication of the case definitions by GAIA, and the extent to which these case definitions have been adopted in maternal vaccine safety research. Methods: A comprehensive search of published literature was undertaken to identify maternal vaccine research studies. PubMed, EMBASE, Web of Science, and Cochrane were searched using a combination of MeSH terms and keyword searches to identify observational or interventional studies that examined vaccine safety in pregnant women with a comparator group. A two-reviewer screening process was undertaken, and a narrative synthesis of the results presented. Results: 14,737 titles were identified from database searches, 435 titles were selected as potentially relevant, 256 were excluded, the remaining 116 papers were included. Influenza vaccine was the most studied (25.0%), followed by TDaP (20.7%) and SARS-CoV-2 (12.9%).Ninety-one studies (78.4%) were conducted in high-income settings. Forty-eight (41.4%) utilised electronic health-records. The majority focused on reporting adverse events of special interest (AESI) in pregnancy (65.0%) alone or in addition to reactogenicity (27.6%). The most frequently reported AESI were preterm birth, small for gestational age and hypertensive disorders. Fewer than 10 studies reported use of GAIA definitions. Gestational age assessment was poorly described; of 39 studies reporting stillbirths 30.8% provided no description of the gestational age threshold. Conclusions: Low-income settings remain under-represented in comparative maternal vaccine safety research. There has been poor uptake of GAIA case definitions. A lack of harmonisation and standardisation persists limiting comparability of the generated safety data.

3.
Vaccine ; 42(6): 1352-1362, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38310014

RESUMO

BACKGROUND: Background epidemiologic population data from low- and middle-income countries (LMIC), on maternal, foetal and neonatal adverse outcomes are limited. We aimed to estimate the incidence of maternal, foetal and neonatal adverse outcomes at South African maternal vaccine trial sites as reported directly in the clinical notes as well as using the 'Global Alignment of Immunization Safety Assessment in Pregnancy' case definitions (GAIA-CDs). GAIA-CDs were utilized as a tool to standardise data collection and outcome assessment, and the applicability and utility of the GAIA-CDs was evaluated in a LMIC observational study. METHODS: We conducted a retrospective record review of maternity and neonatal case records for births that occurred in Soweto, Inner City- Johannesburg and Metro-East Cape Town, South Africa, between 1st July 2017 and 30th June 2018. Study staff abstracted data from randomly selected medical charts onto standardized study-specific forms. Incidence (per 100,000 population) was calculated for adverse maternal, foetal and neonatal outcomes, which were identified as priority outcomes in vaccine safety studies by the Brighton Collaboration and World Health Organization. Outcomes reported directly in the clinical notes and outcomes which fulfilled GAIA-CDs were compared. Incidence of outcomes was calculated by combining cases which were either reported in clinical notes by attending physicians and/ or fulfilled GAIA-CDs. FINDINGS: Of 9371 pregnant women enrolled, 27·6% were HIV-infected, 19·9% attended antenatal clinic in the 1st trimester of pregnancy and 55·3% had ≥1 ultrasound examination. Fourteen percent of women had hypertensive disease of pregnancy, 1·3% had gestational diabetes mellitus and 16% experienced preterm labour. There were 150 stillbirths (1·6%), 26·8% of infants were preterm and five percent had microcephaly. Data available in clinical notes for some adverse outcomes, including maternal- & neonatal death, severe pre-eclampsia/ eclampsia, were able to fulfil GAIA-CDs criteria for all of the clinically-reported cases, however, missing data required to fulfil other GAIA-CD criteria (including stillbirth, gestational diabetes mellitus and gestational hypertension) led to poor correlation between clinically-reported adverse outcomes and outcomes fulfilling GAIA-CDs. Challenges were also encountered in accurately ascertaining gestational age. INTERPRETATION: This study contributes to the expanding body of data on background rates of adverse maternal and foetal/ neonatal outcomes in LMICs. Utilization of GAIA-CDs assists with alignment of data, however, some GAIA-CDs require amendment to improve the applicability in LMICs. FUNDING: This study was funded by Pfizer (Inc).


Assuntos
Diabetes Gestacional , Morte Materna , Vacinas , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , África do Sul/epidemiologia , Natimorto/epidemiologia , Vacinas/efeitos adversos
4.
Nat Immunol ; 24(7): 1161-1172, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37322179

RESUMO

Despite the success of COVID-19 vaccines, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern have emerged that can cause breakthrough infections. Although protection against severe disease has been largely preserved, the immunological mediators of protection in humans remain undefined. We performed a substudy on the ChAdOx1 nCoV-19 (AZD1222) vaccinees enrolled in a South African clinical trial. At peak immunogenicity, before infection, no differences were observed in immunoglobulin (Ig)G1-binding antibody titers; however, the vaccine induced different Fc-receptor-binding antibodies across groups. Vaccinees who resisted COVID-19 exclusively mounted FcγR3B-binding antibodies. In contrast, enhanced IgA and IgG3, linked to enriched FcγR2B binding, was observed in individuals who experienced breakthrough. Antibodies unable to bind to FcγR3B led to immune complex clearance and resulted in inflammatory cascades. Differential antibody binding to FcγR3B was linked to Fc-glycosylation differences in SARS-CoV-2-specific antibodies. These data potentially point to specific FcγR3B-mediated antibody functional profiles as critical markers of immunity against COVID-19.


Assuntos
COVID-19 , Vacinas , Humanos , ChAdOx1 nCoV-19 , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais , Imunoglobulina G , Receptores Fc/genética , Anticorpos Neutralizantes , Vacinação
6.
Vaccine ; 41(23): 3486-3492, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37149443

RESUMO

COVID-19 vaccine efficacy (VE) has been observed to vary against antigenically distinct SARS-CoV-2 variants of concern (VoC). Here we report the final analysis of VE and safety from COV005: a phase 1b/2, multicenter, double-blind, randomized, placebo-controlled study of primary series AZD1222 (ChAdOx1 nCoV-19) vaccination in South African adults aged 18-65 years. South Africa's first, second, and third waves of SARS-CoV-2 infections were respectively driven by the ancestral SARS-CoV-2 virus (wild type, WT), and SARS-CoV-2 Beta and Delta VoCs. VE against asymptomatic and symptomatic infection was 90.6% for WT, 6.7% for Beta and 77.1% for Delta. No cases of severe COVID-19 were documented ahead of unblinding. Safety was consistent with the interim analysis, with no new safety concerns identified. Notably, South Africa's Delta wave occurred ≥ 9 months after primary series vaccination, suggesting that primary series AZD1222 vaccination offers a good durability of protection, potentially due to an anamnestic response. Clinical trial identifier: CT.gov NCT04444674.


Assuntos
COVID-19 , ChAdOx1 nCoV-19 , Adulto , Humanos , SARS-CoV-2/genética , Vacinas contra COVID-19/efeitos adversos , África do Sul , COVID-19/prevenção & controle , Vacinação
7.
Int J Gynaecol Obstet ; 162(1): 29-38, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37194339

RESUMO

In 2014, the Global Alignment on Immunization safety Assessment in pregnancy consortium (GAIA) was formed, with the goal of developing a harmonized, globally-concerted approach to actively monitor the safety of vaccines in pregnancy. A total of 26 standardized definitions for the classification of adverse events have been developed. The aim of this review was to identify and describe studies undertaken to assess the performance of these definitions. A literature search was undertaken to identify published studies assessing the performance of the definitions, and reference lists were snowballed. Data were abstracted by two investigators and a narrative review of the results is presented. Four studies that have evaluated 13 GAIA case definitions (50%) were identified. Five case definitions have been assessed in high-income settings only. Recommendations have been made by the investigators to improve the performance of the definitions. These include ensuring consistency across definitions, removal of the potential for ambiguity or variations in interpretation and ensuring that higher-level criteria are acceptable at lower levels of confidence. Future research should prioritize the key case definitions that have not been assessed in low- and middle-income settings, as well as the 13 that have not undergone any validation.


Assuntos
Vacinas , Gravidez , Feminino , Humanos , Vacinas/efeitos adversos , Vacinação , Imunização/efeitos adversos , Família , Renda
8.
Vaccines (Basel) ; 11(5)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37243064

RESUMO

In combatting COronaVIrus Disease 2019 (COVID-19), immunization is the most prominent strategy. However, vaccination hesitancy-meaning delays in accepting or denying inoculation regardless of availability-has been identified as an essential threat to global health. Attitudes and perceptions play a pivotal role in vaccine acceptability. Meanwhile, uptake in South Africa's rollout has been particularly disappointing among youths. For that reason, we explored attitudes and perceptions of COVID-19 in 380 youths in Soweto and Thembelihle, South Africa, between April and June 2022. A staggering hesitancy rate of 79.2 percent was recorded (301/380). We found negative attitudes and confounded perceptions of COVID-19 to be fueled by medical mistrust and misinformation, with online channels as the main sources of non- and counterfactual claims stemming mostly from unregulated social media popular with youths. Understanding its underpinnings-and enhancing means of curbing vaccine hesitancy-will be paramount in boosting uptake in South Africa's immunization program, particularly among youths.

9.
Lancet Child Adolesc Health ; 7(5): 326-335, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36934731

RESUMO

BACKGROUND: Pneumococcal conjugate vaccine (PCV) immunisation has reduced vaccine-serotype colonisation and invasive pneumococcal disease in South Africa, providing the opportunity to consider transitioning from a two-dose (2 + 1) to one-dose (1 + 1) primary series and a booster dose. METHODS: In this single-centre, open-label, randomised trial done in South Africa, infants aged 35-49 days without HIV infection, without childhood immunisations except for BCG and polio, and with gestation age at delivery of at least 37 weeks of age, a birthweight of at least 2500 g, and weight of at least 3500 g at the time of enrolment were randomly assigned (1:1:1:1:1:1), through block randomisation (block size of 30), to receive a single priming dose of ten-valent PCV (PCV10) or 13-valent PCV (PCV13) at either 6 weeks (6-week 1 + 1 group) or 14 weeks (14-week 1 + 1 group), compared with two priming doses at 6 weeks and 14 weeks (2 + 1 group), followed by a booster dose at 9 months of age in all groups. The primary objective of the trial has been published previously. We report the secondary objective of the effect of alternative doses of PCV10 and PCV13 on serotype-specific Streptococcus pneumoniae colonisation at 9 months, 15 months, and 18 months of age and a further exploratory analysis in which we assessed non-inferiority of serotype-specific serum IgG geometric mean concentrations 1 month after the booster (10 months of age) and the percentage of participants with serotype-specific IgG titre above the putative thresholds associated with a risk reduction of serotype-specific colonisation between the 1 + 1 and 2 + 1 groups for both vaccines. Non-inferiority was established if the lower limit of the 95% CI for the difference between the proportion of participants (1 + 1 group vs 2 + 1 group) above the putative thresholds was greater than or equal to -10%. All analyses were done in the modified intention-to-treat population, which included all participants who received PCV10 or PCV13 according to assigned randomisation group and for whom laboratory results were available. The trial is registered with ClinicalTrials.gov, NCT02943902. FINDINGS: 1564 nasopharyngeal swabs were available for molecular serotyping from 600 infants who were enrolled (100 were randomly assigned to each of the six study groups) between Jan 9 and Sept 20, 2017. There was no significant difference in the prevalence of overall or non-vaccine serotype colonisation between all PCV13 or PCV10 groups. PCV13 serotype colonisation was lower at 15 months of age in the 14-week 1 + 1 group than in the 2 + 1 group (seven [8%] of 85 vs 17 [20%] of 87; odds ratio 0·61 [95% CI 0·38-0·97], p=0·037), but no difference was seen at 9 months (nine [11%] of 86 vs ten [11%] of 89; 0·92 [0·60-1·55], p=0·87) or 18 months (nine [11%] of 85 vs 11 [14%] of 87; 0·78 [0·45-1·22], p=0·61). Compared with the PCV13 2 + 1 group, both PCV13 1 + 1 groups did not meet the non-inferiority criteria for serotype-specific anti-capsular antibody concentrations above the putative thresholds purportedly associated with risk reduction for colonisation; however, the PCV10 14-week 1 + 1 group was non-inferior to the PCV10 2 + 1 group. INTERPRETATION: The serotype-specific colonisation data reported in this study together with the primary immunogenicity endpoints of the control trial support transitioning to a reduced 1 + 1 schedule in South Africa. Ongoing monitoring of colonisation should, however, be undertaken immediately before and after transitioning to a PCV 1 + 1 schedule to serve as an early indicator of whether PCV 1 + 1 could lead to an increase in vaccine-serotype disease. FUNDING: The Bill & Melinda Gates Foundation.


Assuntos
Infecções por HIV , Streptococcus pneumoniae , Lactente , Humanos , Criança , África do Sul/epidemiologia , Infecções por HIV/tratamento farmacológico , Anticorpos Antibacterianos/farmacologia , Vacinas Conjugadas , Imunoglobulina G
10.
Int J Infect Dis ; 129: 240-250, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36805325

RESUMO

OBJECTIVES: We determined the pulse oximetry benefit in pediatric pneumonia mortality risk stratification and chest-indrawing pneumonia in-hospital mortality risk factors. METHODS: We report the characteristics and in-hospital pneumonia-related mortality of children aged 2-59 months who were included in the Pneumonia Research Partnership to Assess WHO Recommendations dataset. We developed multivariable logistic regression models of chest-indrawing pneumonia to identify mortality risk factors. RESULTS: Among 285,839 children, 164,244 (57.5%) from hospital-based studies were included. Pneumonia case fatality risk (CFR) without pulse oximetry measurement was higher than with measurement (5.8%, 95% confidence interval [CI] 5.6-5.9% vs 2.1%, 95% CI 1.9-2.4%). One in five children with chest-indrawing pneumonia was hypoxemic (19.7%, 95% CI 19.0-20.4%), and the hypoxemic CFR was 10.3% (95% CI 9.1-11.5%). Other mortality risk factors were younger age (either 2-5 months [adjusted odds ratio (aOR) 9.94, 95% CI 6.67-14.84] or 6-11 months [aOR 2.67, 95% CI 1.71-4.16]), moderate malnutrition (aOR 2.41, 95% CI 1.87-3.09), and female sex (aOR 1.82, 95% CI 1.43-2.32). CONCLUSION: Children with a pulse oximetry measurement had a lower CFR. Many children hospitalized with chest-indrawing pneumonia were hypoxemic and one in 10 died. Young age and moderate malnutrition were risk factors for in-hospital chest-indrawing pneumonia-related mortality. Pulse oximetry should be integrated in pneumonia hospital care for children under 5 years.


Assuntos
Desnutrição , Pneumonia , Criança , Humanos , Feminino , Lactente , Pré-Escolar , Mortalidade Hospitalar , Pneumonia/diagnóstico , Oximetria , Organização Mundial da Saúde , Medição de Risco
11.
Viruses ; 15(2)2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36851662

RESUMO

Vaccines against SARS-CoV-2 have been pivotal in overcoming the COVID-19 pandemic yet understanding the subsequent outcomes and immunological effects remain crucial, especially for at-risk groups e.g., people living with human immunodeficiency virus (HIV) (PLWH). In this study we report the longitudinal IgA and IgG antibody titers, as well as antibody-mediated angiotensin converting enzyme 2 (ACE2) binding blockade, against the SARS-CoV-2 spike (S) proteins after 1 and 2 doses of the ChAdOx1 nCoV-19 vaccine in a population of Black PLWH. Here, we report that PLWH (N = 103) did not produce an anti-S IgA response after infection or vaccination, however, anti-S IgG was detected in response to vaccination and infection, with the highest level detected for infected vaccinated participants. The anti-IgG and ACE2 blockade assays revealed that both vaccination and infection resulted in IgG production, however, only vaccination resulted in a moderate increase in ACE2 binding blockade to the ancestral S protein. Vaccination with a previous infection results in the greatest anti-S IgG and ACE2 blockade for the ancestral S protein. In conclusion, PLWH produce an anti-S IgG response to the ChAdOx1 nCoV-19 vaccine and/or infection, and ChAdOx1 nCoV-19 vaccination with a previous infection produced more neutralizing antibodies than vaccination alone.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Humanos , Anticorpos Bloqueadores , Anticorpos Neutralizantes , ChAdOx1 nCoV-19 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunoglobulina A , Pandemias , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Imunoglobulina G
12.
Vaccine ; 41(5): 1153-1160, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36621408

RESUMO

BACKGROUND: Immunogenicity and safety up to 5 years after administration of 1 or 2 doses of quadrivalent meningococcal serogroup A, C, W, and Y tetanus toxoid conjugate vaccine (MenACWY-TT) given alone or with 13-valent pneumococcal conjugate vaccine (PCV13) in children was investigated. METHODS: This phase 3 study randomized healthy 12-24-month-olds to MenACWY-TT at Month 0 (ACWY1d), MenACWY-TT at Months 0 and 2 (ACWY2d), MenACWY-TT and PCV13 at Month 0 (Co-Ad), or PCV13 at Month 0 and MenACWY-TT at Month 2 (PCV13/ACWY). Immune responses 1, 3, and 5 years after primary vaccination were evaluated with serum bactericidal activity using rabbit complement (rSBA) titers ≥ 1:8 and geometric mean titers (GMTs). Evaluation of serious adverse events up to 5 years after primary vaccination are reported. RESULTS: Of the 802 children randomized in the study, 619 completed the study through Year 5. Immune responses after vaccination declined over time but were higher 5 years after vaccination compared with levels before vaccination. At Year 5, the percentages of children with rSBA titers ≥ 1:8 across all serogroups were 20.5 %-58.6 %, 28.4 %-65.8 %, 23.9 %-52.8 %, and 19.4 %-55.8 % in the ACWY1d, ACWY2d, Co-Ad, and PCV13/ACWY groups, respectively. Comparable antibody persistence at Year 5 was observed for participants receiving 1 or 2 doses of MenACWY-TT, although GMTs were elevated in those who received 2 versus 1 dose. The percentage of children with protective antibody titers at Year 5 was similar in participants who received PCV13 and MenACWY-TT compared with that observed for participants who only received 1 or 2 MenACWY-TT doses. No new safety concerns were identified during the study period. CONCLUSION: Antibody responses persisted in the majority of children up to 5 years after primary vaccination with MenACWY-TT administered in a 1- or 2-dose regimen with or without PCV13, with no new safety concerns identified. CLINICALTRIALS: gov Identifier NCT01939158; EudraCT number 2013-001083-28.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , Humanos , Vacinas Conjugadas/efeitos adversos , Anticorpos Antibacterianos , Toxoide Tetânico , Infecções Meningocócicas/prevenção & controle
13.
Lancet Infect Dis ; 23(1): e2-e21, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35952703

RESUMO

Respiratory syncytial virus is the second most common cause of infant mortality and a major cause of morbidity and mortality in older adults (aged >60 years). Efforts to develop a respiratory syncytial virus vaccine or immunoprophylaxis remain highly active. 33 respiratory syncytial virus prevention candidates are in clinical development using six different approaches: recombinant vector, subunit, particle-based, live attenuated, chimeric, and nucleic acid vaccines; and monoclonal antibodies. Nine candidates are in phase 3 clinical trials. Understanding the epitopes targeted by highly neutralising antibodies has resulted in a shift from empirical to rational and structure-based vaccine and monoclonal antibody design. An extended half-life monoclonal antibody for all infants is likely to be within 1 year of regulatory approval (from August, 2022) for high-income countries. Live-attenuated vaccines are in development for older infants (aged >6 months). Subunit vaccines are in late-stage trials for pregnant women to protect infants, whereas vector, subunit, and nucleic acid approaches are being developed for older adults. Urgent next steps include ensuring access and affordability of a respiratory syncytial virus vaccine globally. This review gives an overview of respiratory syncytial virus vaccines and monoclonal antibodies in clinical development highlighting different target populations, antigens, and trial results.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Lactente , Feminino , Humanos , Gravidez , Idoso , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Anticorpos Monoclonais/uso terapêutico , Imunização , Anticorpos Antivirais
14.
AIDS ; 37(1): 105-112, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36476455

RESUMO

OBJECTIVES: This study aimed to investigate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T-cell responses 14 days after single-dose ChAdOx1 nCoV-19 (AZD1222) vaccination in black Africans with and without HIV in South Africa, as well as determine the effect of AZD1222 vaccination on cell-mediated immune responses in people with HIV (PWH) with prior SARS-CoV-2 infection. METHODS: A total of 70 HIV-uninfected people and 104 PWH were prospectively enrolled in the multicentre, randomized, double-blinded, placebo-controlled, phase Ib/IIa trial (COV005). Peripheral blood mononuclear cells (PBMCs) were collected from trial participants 14 days after receipt of first dose of study treatment (placebo or AZD1222 vaccine). T-cell responses against the full-length spike (FLS) glycoprotein of wild-type SARS-CoV-2 and mutated S-protein regions found in the Alpha, Beta and Delta variants were assessed using an ex-vivo ELISpot assay. RESULTS: Among AZD1222 recipients without preceding SARS-CoV-2 infection, T-cell responses to FLS of wild-type SARS-CoV-2 were similarly common in PWH and HIV-uninfected people (30/33, 90.9% vs. 16/21, 76.2%; P = 0.138); and magnitude of response was similar among responders (78 vs. 56 SFCs/106 PBMCs; P = 0.255). Among PWH, AZD1222 vaccinees with prior SARS-CoV-2 infection, displayed a heightened T-cell response magnitude compared with those without prior infection (186 vs. 78 SFCs/106 PBMCs; P = 0.001); and similar response rate (14/14, 100% vs. 30/33, 90.9%; P = 0.244). CONCLUSION: Our results indicate comparable T-cell responses following AZD1222 vaccination in HIV-uninfected people and PWH on stable antiretroviral therapy. Our results additionally show that hybrid immunity acquired through SARS-CoV-2 infection and AZD1222 vaccination, induce a heightened T-cell response.


Assuntos
COVID-19 , Infecções por HIV , Vacinas , Humanos , SARS-CoV-2 , ChAdOx1 nCoV-19 , COVID-19/prevenção & controle , Leucócitos Mononucleares , Linfócitos T , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico
15.
Lancet Infect Dis ; 23(3): 295-306, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36273491

RESUMO

BACKGROUND: COVID-19 vaccine rollout is lagging in Africa, where there has been a high rate of SARS-CoV-2 infection. We aimed to evaluate the effect of SARS-CoV-2 infection before vaccination with the ChAdOx-nCoV19 (AZD1222) vaccine on antibody responses through to 180 days. METHODS: We did an unmasked post-hoc immunogenicity analysis after the first and second doses of AZD1222 in a randomised, placebo-controlled, phase 1b-2a study done in seven locations in South Africa. AZD1222 recipients who were HIV-uninfected, were stratified into baseline seropositive or seronegative groups using the serum anti-nucleocapsid (anti-N) immunoglobulin G (IgG) electroluminescence immunoassay to establish SARS-CoV-2 infection before the first dose of AZD1222. Binding IgG to spike (anti-S) and receptor binding domain (anti-RBD) were measured before the first dose (day 0), second dose (day 28), day 42, and day 180. Neutralising antibody (NAb) against SARS-CoV-2 variants D614G, beta, delta, gamma, and A.VOI.V2, and omicron BA1 and BA.4 variants, were measured by pseudovirus assay (day 28, day 42, and day 180). This trial is registered with ClinicalTrials.gov, NCT04444674, and the Pan African Clinicals Trials Registry, PACTR202006922165132. FINDINGS: Of 185 individuals who were randomly assigned to AZD1222, we included 91 individuals who were baseline seropositive and 58 who were baseline seronegative, in the final analysis. In the seropositive group, there was little change of anti-S IgG (and anti-RBD IgG) or neutralising antibody (NAb) titres at day 42 compared with at day 28. Anti-S (and anti-RBD) IgG geometric mean concentrations (GMCs) were higher throughout in the seropositive compared with the seronegative group, including at day 180 (GMCs 517·8 [95% CI 411·3-651·9] vs 82·1 [55·2-122·3] BAU/mL). Also D614G NAb geometric mean titres (GMTs) were higher in the seropositive group than the seronegative group, as was the percentage with titres of at least 185 (80% putative risk reduction threshold [PRRT] against wild-type-alpha COVID-19), including at day 180 (92·0% [74·0-99·0] vs 18·2% [2·3-51·8). Similar findings were observed for beta, A.VOI.V2, and gamma. For delta, BA.1, and BA.4, NAb GMTs and the proportion with titres above the PRRT were substantially higher in the seropositive compared with seronegative group at day 28 and day 42, but no longer differed between the groups by day 180. INTERPRETATION: A single dose of AZD1222 in the general African population, where COVID-19 vaccine coverage is low and SARS-CoV-2 seropositivity is 90%, could enhance the magnitude and quality of antibody responses to SARS-CoV-2. FUNDING: The Bill & Melinda Gates Foundation, the South African Medical Research Council, the UK Research and Innovation, the UK National Institute for Health Research, and the South African Medical Research Council. TRANSLATION: For the Zulu translation of the abstract see Supplementary Materials section.


Assuntos
COVID-19 , Vacinas , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , ChAdOx1 nCoV-19 , Vacinas contra COVID-19 , Imunidade Humoral , Imunogenicidade da Vacina , Imunoglobulina G , SARS-CoV-2 , África do Sul , Vacinação
16.
J Glob Health ; 12: 04075, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36579417

RESUMO

Background: The existing World Health Organization (WHO) pneumonia case management guidelines rely on clinical symptoms and signs for identifying, classifying, and treating pneumonia in children up to 5 years old. We aimed to collate an individual patient-level data set from large, high-quality pre-existing studies on pneumonia in children to identify a set of signs and symptoms with greater validity in the diagnosis, prognosis, and possible treatment of childhood pneumonia for the improvement of current pneumonia case management guidelines. Methods: Using data from a published systematic review and expert knowledge, we identified studies meeting our eligibility criteria and invited investigators to share individual-level patient data. We collected data on demographic information, general medical history, and current illness episode, including history, clinical presentation, chest radiograph findings when available, treatment, and outcome. Data were gathered separately from hospital-based and community-based cases. We performed a narrative synthesis to describe the final data set. Results: Forty-one separate data sets were included in the Pneumonia Research Partnership to Assess WHO Recommendations (PREPARE) database, 26 of which were hospital-based and 15 were community-based. The PREPARE database includes 285 839 children with pneumonia (244 323 in the hospital and 41 516 in the community), with detailed descriptions of clinical presentation, clinical progression, and outcome. Of 9185 pneumonia-related deaths, 6836 (74%) occurred in children <1 year of age and 1317 (14%) in children aged 1-2 years. Of the 285 839 episodes, 280 998 occurred in children 0-59 months old, of which 129 584 (46%) were 2-11 months of age and 152 730 (54%) were males. Conclusions: This data set could identify an improved specific, sensitive set of criteria for diagnosing clinical pneumonia and help identify sick children in need of referral to a higher level of care or a change of therapy. Field studies could be designed based on insights from PREPARE analyses to validate a potential revised pneumonia algorithm. The PREPARE methodology can also act as a model for disease database assembly.


Assuntos
Pneumonia , Masculino , Criança , Humanos , Lactente , Recém-Nascido , Pré-Escolar , Feminino , Pneumonia/tratamento farmacológico , Administração de Caso , Organização Mundial da Saúde , Algoritmos , Pesquisa
17.
J Thorac Dis ; 14(10): 4150-4172, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36389298

RESUMO

Pneumococcal infections remain a common global cause of significant morbidity and mortality. The first recommendations for adult pneumococcal vaccination, published in South Africa in 1999, contained information only on the 23-valent polysaccharide vaccine (PPV23). With the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) for use in adults and the perceived uncertainty that most clinicians had regarding use of these vaccines in adults, these vaccine recommendations were updated in 2022. A Working Group, which consisted of individuals in various fields of medical practice in South Africa, who were from different areas of the country, and included clinicians from both the public and private sectors, was assembled to revise the recommendations. The expertise of the participants varied widely, dependent on their training and specialty, and encompassed different organ systems, disease conditions, and/or practice types. Each participant was allocated a different section, based on their expertise, for which they were required to do an extensive review of the current literature and write their section. The entire working group then reviewed the complete document several times, following additional comments and recommendations. This update contains recommendations for the use of both PPV23 and PCV13, either alone, or in sequence, both in vaccine naïve and in previously vaccinated individuals. It includes both age and risk categories, and encompasses the elderly (≥65 years), as well as younger adults (<65 years) with comorbid conditions or with high-risk conditions and/or immunocompromise. It is hoped that this review and its associated vaccine recommendations will clarify for clinicians, from all spheres of practice in South Africa, how, where, and when pneumococcal vaccines should be used in adults, with the ultimate goal of significantly increasing the appropriate use of these vaccines, in order to decrease the substantial morbidity and mortality associated with pneumococcal infections in adults in South Africa. Furthermore, it is hoped that this review of local epidemiological data and the manner in which this information was interpreted in the development of these local vaccine recommendations, could be used as an example for other regions of the world, to tailor their recommendations to locally available epidemiological data.

18.
Open Forum Infect Dis ; 9(11): ofac552, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36447608

RESUMO

Background: Influenza vaccination during pregnancy reduces influenza-associated illness in the women and their infants, but effectiveness estimates against influenza-associated hospitalization are limited and lacking from settings with high human immunodeficiency virus (HIV) infection prevalence. We assessed the effect of maternal vaccination in HIV-uninfected women and women with HIV in preventing influenza-associated hospitalizations in infants and the women. Methods: During 2015-2018, influenza vaccination campaigns targeting pregnant women were augmented at selected antenatal clinics; these were coupled with prospective hospital-based surveillance for acute respiratory or febrile illness in infants aged <6 months and cardiorespiratory illness among pregnant or postpartum women. Vaccine effectiveness (VE) was assessed using a test-negative case-control study. Results: Overall, 71 influenza-positive and 371 influenza-negative infants were included in the analysis; mothers of 26.8% of influenza-positive infants were vaccinated during pregnancy compared with 35.6% of influenza-negative infants, corresponding to an adjusted VE (aVE) of 29.0% (95% confidence interval [CI], -33.6% to 62.3%). When limited to vaccine-matched strains, aVE was 65.2% (95% CI, 11.7%-86.3%). For maternal hospitalizations, 56 influenza-positive and 345 influenza-negative women were included in the analysis, with 28.6% of influenza-positive women being vaccinated compared with 38.3% of influenza-negatives, for an aVE of 46.9% (95% CI, -2.8% to 72.5%). Analysis restricted to HIV-uninfected women resulted in 82.8% (95% CI, 40.7%-95.0%) aVE. No significant aVE (-32.5% [95% CI, -208.7% to 43.1%]) was detected among women with HIV. Conclusions: Influenza vaccination during pregnancy prevented influenza-associated hospitalizations among young infants when infected with vaccine strains and among HIV-uninfected women.

19.
AJOG Glob Rep ; 2(3): 100056, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36276804

RESUMO

BACKGROUND: Preeclampsia is a considerable cause of maternal and infant morbidity and mortality. Although its etiology is unknown, preeclampsia has been described as a state of exaggerated maternal inflammatory response. Therefore, it has been hypothesized that preeclampsia would occur less commonly in states of immune deficiency. OBJECTIVE: This study aimed to compare the prevalence of treated and untreated HIV infections among preeclamptic cases and controls, determine infant outcomes, and evaluate the association between HIV and preeclampsia after adjusting for known predictor variables, including maternal age, gravidity, body mass index, and smoking. STUDY DESIGN: This case-control study investigated the association between preeclampsia and HIV infection using secondary data from an unrelated study. We defined preeclamptic cases as pregnant women who were normotensive until 20 weeks of gestation and thereafter had at least 1 high blood pressure measurement either before or at delivery and proteinuria, defined as protein excretion of ≥300 mg within 24 hours or >2 protein on dipstick urinalysis. The prevalence of HIV infection was compared between cases and controls. Multivariate logistic regression analysis was used to assess the association between preeclampsia and potential confounding variables and reported using odds ratios and 95% confidence intervals. RESULTS: There were 571 cases with preeclampsia and 596 normotensive controls included in this study. The median age was 27 years for cases and 26 years for controls (P=.008). Most participants (69%) had ≥2 previous pregnancies with no difference between the cases and controls (P=.176). Overall, 43% of the participants were obese, with a mean body mass index of 29 (interquartile range, 24.5-34.2), with higher proportions of women who were overweight and obese in the group with preeclampsia (P=.031). The prevalence of HIV was significantly lower in cases than in controls (24% vs 30%, respectively; P=.014). Compared with 16% of infants born preterm to normotensive controls, 48% of infants were born preterm born to women with preeclampsia (P<.001). Compared with 14% of infants born with low birthweight to normotensive controls, 53% of infants were born with low birthweight to women with preeclampsia (P<.0001). Untreated HIV infection was negatively associated with preeclampsia (unadjusted odds ratio, 0.330; 95% confidence interval, 0.197-0.552; P<.0001), whereas factors associated with preeclampsia were advanced maternal age (odds ratio, 1.673; 95% confidence interval, 1.209-2.316; P=.002) and obesity (odds ratio, 1.611; 95% confidence interval, 1.023-2.537; P=.040). After adjusting for maternal age, gravidity, smoking, and body mass index in the multivariate regression, only obesity remained significantly associated with preeclampsia (adjusted odds ratio, 1.624; 95% confidence interval, 1.024-2.575; P=.039). CONCLUSION: Before the large-scale rollout of antiretroviral therapy in a setting with a high burden of HIV and preeclampsia, untreated HIV infection was found to have a protective effect against preeclampsia. The protective effect against preeclampsia was not apparent for HIV infection treated with antiretroviral therapy.

20.
Clin Infect Dis ; 75(Suppl 1): S11-S17, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35680552

RESUMO

Within 2 years after the start of the coronavirus disease 2019 (COVID-19) pandemic, novel severe acute respiratory syndrome coronavirus 2 vaccines were developed, rigorously evaluated in large phase 3 trials, and administered to more than 5 billion individuals globally. However, adverse events of special interest (AESIs) have been described post-implementation, including myocarditis after receipt of messenger RNA (mRNA) vaccines and thrombosis with thrombocytopenia syndrome after receipt of adenoviral vector vaccines. AESIs are rare (<1 to 10/100 000 vaccinees) and less frequent than COVID-19 complications, though they have associated morbidity and mortality. The diversity of COVID-19 vaccine platforms (eg, mRNA, viral vector, protein) and rates of AESIs both between and within platforms (eg, higher rate of myocarditis after mRNA-1273 vs BNT162b2 vaccines) present an important opportunity to advance vaccine safety science. The International Network of Special Immunization Services has been formed with experts in vaccine safety, systems biology, and other relevant disciplines to study cases of AESIs and matched controls to uncover the pathogenesis of rare AESIs and inform vaccine development.


Assuntos
COVID-19 , Miocardite , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Humanos , Imunização , Pandemias/prevenção & controle , RNA Mensageiro
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