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1.
Sci Rep ; 14(1): 7709, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565882

RESUMEN

The present study aimed at evaluating the YF-specific neutralizing antibody profile besides a multiparametric analysis of phenotypic/functional features of cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF vaccine, administered as a single subcutaneous injection. The immunological parameters of each volunteer was monitored at two time points, referred as: before (Day 0) [Non-Vaccinated, NV(D0)] and after vaccination (Day 30-45) [Primary Vaccinees, PV(D30-45)]. Data demonstrated high levels of neutralizing antibodies for PV(D30-45) leading to a seropositivity rate of 93%. A broad increase of systemic soluble mediators with a mixed profile was also observed for PV(D30-45), with IFN-γ and TNF-α presenting the highest baseline fold changes. Integrative network mapping of soluble mediators showed increased correlation numbers in PV(D30-45) as compared to NV(D0) (532vs398). Moreover, PV(D30-45) exhibited increased levels of Terminal Effector (CD45RA+CCR7-) CD4+ and CD8+ T-cells and Non-Classical memory B-cells (IgD+CD27+). Dimensionality reduction of Mass Cytometry data further support these findings. A polyfunctional cytokine profile (TNF-α/IFN-γ/IL-10/IL-17/IL-2) of T and B-cells was observed upon in vitro antigen recall. Mapping and kinetics timeline of soluble mediator signatures for PV(D30-45) further confirmed the polyfunctional profile upon long-term in vitro culture, mediated by increased levels of IFN-γ and TNF-α along with decreased production of IL-10. These findings suggest novel insights of correlates of protection elicited by the 1/5 fractional dose of 17DD-YF vaccine.


Asunto(s)
Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Humanos , Adulto , Anticuerpos Neutralizantes , Interleucina-10 , Anticuerpos Antivirales , Factor de Necrosis Tumoral alfa , Linfocitos T CD8-positivos , Vacunación
2.
Biomolecules ; 14(3)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38540733

RESUMEN

Neuropeptides are the main regulators of physiological, developmental, and behavioural processes in insects. Three insect neuropeptide systems, the adipokinetic hormone (AKH), corazonin (Crz), and adipokinetic hormone/corazonin-related peptide (ACP), and their cognate receptors, are related to the vertebrate gonadotropin (GnRH) system and form the GnRH superfamily of peptides. In the current study, the two signalling systems, AKH and ACP, of the yellow fever mosquito, Aedes aegypti, were comparatively investigated with respect to ligand binding to their respective receptors. To achieve this, the solution structure of the hormones was determined by nuclear magnetic resonance distance restraint methodology. Atomic-scale models of the two G protein-coupled receptors were constructed with the help of homology modelling. Thereafter, the binding sites of the receptors were identified by blind docking of the ligands to the receptors, and models were derived for each hormone system showing how the ligands are bound to their receptors. Lastly, the two models were validated by comparing the computational results with experimentally derived data available from the literature. This mostly resulted in an acceptable agreement, proving the models to be largely correct and usable. The identification of an antagonist versus a true agonist may, however, require additional testing. The computational data also explains the exclusivity of the two systems that bind only the cognate ligand. This study forms the basis for further drug discovery studies.


Asunto(s)
Aedes , Hormonas de Insectos , Neuropéptidos , Oligopéptidos , Ácido Pirrolidona Carboxílico/análogos & derivados , Fiebre Amarilla , Animales , Ligandos , Modelos Químicos , Filogenia , Evolución Molecular , Neuropéptidos/metabolismo , Hormona Liberadora de Gonadotropina/genética , Hormona Liberadora de Gonadotropina/metabolismo
3.
Trials ; 25(1): 216, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532475

RESUMEN

RATIONALE: The effectiveness of immunisation with pneumococcal conjugate vaccine (PCV) has been demonstrated in many countries. However, the global impact of PCV is limited by its cost, which has prevented its introduction in some countries. Reducing the cost of PCV programmes will facilitate further vaccine introductions and improve the sustainability of PCV in low-income countries when they transition from subsidised vaccine supply. We are conducting a large, population-level, cluster-randomised field trial (PVS) of an alternative reduced-dose schedule of PCV compared to the standard schedule. We are also conducting a nested sub-study at the individual level to investigate the immunogenicity of the two schedules and their effects on pneumococcal carriage acquisition (PVS-AcqImm). METHODS AND DESIGN: PVS-AcqImm is a prospective, cluster-randomised trial of an alternative schedule of one dose of PCV scheduled at age 6 weeks with a booster dose at age 9 months compared to the standard of three primary doses scheduled at 6, 10, and 14 weeks of age. Sub-groups within the alternative schedule group receive yellow fever vaccine separately or co-administered with PCV at 9 months of age. The primary endpoints are (a) concentrations of vaccine-type anti-pneumococcal IgG at 18 months of age, (b) proportions with yellow fever neutralising antibody titre ≥ 1:8 4 weeks after separate or co-administration of PCV and yellow fever vaccines, and (c) rate of nasopharyngeal vaccine-type pneumococcal acquisition from 10-14 months of age. Participants and field staff are not masked to group allocation while measurement of the laboratory endpoints is masked. Approximately equal numbers of participants are resident in each of 28 randomly allocated geographic clusters (14 clusters in each group); 784 enrolled for acquisition measurements and 336 for immunogenicity measurements. PURPOSE: This statistical analysis plan (SAP) describes the PVS-AcqImm cohort and follow-up criteria to be used in different analyses. The SAP defines the endpoints and describes how adherence to the interventions will be presented. We describe the approach to analyses and how we will account for the effect of clustering. Defining the SAP prior to the conduct of analysis will avoid bias in analyses that may arise from prior knowledge of trial findings. TRIAL REGISTRATION: ISRCTN, ISRCTN7282161328. Registered on 28 November 2019. https://www.isrctn.com/ISRCTN72821613 . PROTOCOL: MRCG SCC number 1670, LSHTM Ref 17683. Current protocol version: 6.0, 24 May 2021. Version: 1.0 (5 April 2023); SAP revisions-none.


Asunto(s)
Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Humanos , Lactante , Esquemas de Inmunización , Vacunas Neumococicas , Estudios Prospectivos , Streptococcus pneumoniae , Vacunación/métodos , Vacunas Conjugadas
4.
Vaccine ; 42(11): 2729-2732, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38514353

RESUMEN

Studies on yellow fever vaccine (YF) in chronic kidney disease (CKD) patients are scarce. This cross-sectional study aimed to evaluate YF neutralizing antibody seroprevalence and titers in previously vaccinated adults with CKD, on dialysis (D-CKD) or not (ND-CKD), compared to healthy persons. The micro Plaque Reduction Neutralization-Horseradish Peroxidase (µPRN-HP) test was used. Antibody titers were expressed as the reciprocal of the highest dilution that neutralized the challenge virus by 50 % (µPRN50). Seropositivity cut-off was set at ≥ 1:100. We included 153 participants: 46 ND-CKD, 50 D-CKD and 57 healthy adults. Median ages were 58.3, 55 and 52.2 years, respectively. Median time since YF vaccination was 22.3, 18.5 and 48.3 months respectively. There were no statistically significant differences in YF seroprevalence and neutralizing antibodies titers among groups: 100 % of ND-CKD; 96 % of D-CKD and 100 % of healthy participants were seropositive. Geometric mean titers (GMT) were 818.5, 683.0 and 665.5, respectively (p = 0.289).


Asunto(s)
Insuficiencia Renal Crónica , Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Adulto , Humanos , Fiebre Amarilla/prevención & control , Anticuerpos Neutralizantes , Estudios Transversales , Estudios Seroepidemiológicos , Anticuerpos Antivirales , Virus de la Fiebre Amarilla , Vacunación , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia
5.
J Travel Med ; 31(3)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38438165

RESUMEN

BACKGROUND: Vaccination plays a critical role in mitigating the burden associated with yellow fever (YF). However, there is a lack of comprehensive evidence on the humoral response to primary vaccination in the paediatric population, with several questions debated, including the response when the vaccine is administered at early ages, the effect of co-administration with other vaccines, the duration of immunity and the use of fractional doses, among others. This study summarizes the existing evidence regarding the humoral response to primary YF vaccination in infants and children. METHODS: Studies on the humoral response to primary YF vaccination in children aged 12 years or younger were reviewed. The humoral vaccine response rate (VRR), i.e. the proportion of children who tested positive for vaccine-induced YF-specific neutralizing antibodies, was pooled through random-effects meta-analysis and categorized based on the time elapsed since vaccination. Subgroup, meta-regression and sensitivity analyses were performed. RESULTS: A total of 33 articles met the inclusion criteria, with all but one conducted in countries where YF is endemic. A total of 14 028 infants and children entered this systematic review. Within three months following vaccination, the pooled VRR was 91.9% (95% CI 89.8-93.9). A lower VRR was observed with the 17DD vaccine at the meta-regression analysis. No significant differences in immunogenicity outcomes were observed based on age, administration route, co-administration with other vaccines, or fractional dosing. Results also indicate a decline in VRR over time. CONCLUSIONS: Primary YF vaccination effectively provides humoral immunity in paediatric population. However, humoral response declines over time, and this decline is observable after the first 18 months following vaccination. A differential response according to the vaccine substrain was also observed. This research has valuable implications for stimulating further research on the primary YF vaccination in infants and children, as well as for informing future policies.


Asunto(s)
Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Niño , Lactante , Humanos , Fiebre Amarilla/prevención & control , Anticuerpos Neutralizantes , Vacunación/métodos , Inmunidad Humoral , Anticuerpos Antivirales
6.
Lancet Glob Health ; 12(4): e563-e571, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38485425

RESUMEN

BACKGROUND: There have been declines in global immunisation coverage due to the COVID-19 pandemic. Recovery has begun but is geographically variable. This disruption has led to under-immunised cohorts and interrupted progress in reducing vaccine-preventable disease burden. There have, so far, been few studies of the effects of coverage disruption on vaccine effects. We aimed to quantify the effects of vaccine-coverage disruption on routine and campaign immunisation services, identify cohorts and regions that could particularly benefit from catch-up activities, and establish if losses in effect could be recovered. METHODS: For this modelling study, we used modelling groups from the Vaccine Impact Modelling Consortium from 112 low-income and middle-income countries to estimate vaccine effect for 14 pathogens. One set of modelling estimates used vaccine-coverage data from 1937 to 2021 for a subset of vaccine-preventable, outbreak-prone or priority diseases (ie, measles, rubella, hepatitis B, human papillomavirus [HPV], meningitis A, and yellow fever) to examine mitigation measures, hereafter referred to as recovery runs. The second set of estimates were conducted with vaccine-coverage data from 1937 to 2020, used to calculate effect ratios (ie, the burden averted per dose) for all 14 included vaccines and diseases, hereafter referred to as full runs. Both runs were modelled from Jan 1, 2000, to Dec 31, 2100. Countries were included if they were in the Gavi, the Vaccine Alliance portfolio; had notable burden; or had notable strategic vaccination activities. These countries represented the majority of global vaccine-preventable disease burden. Vaccine coverage was informed by historical estimates from WHO-UNICEF Estimates of National Immunization Coverage and the immunisation repository of WHO for data up to and including 2021. From 2022 onwards, we estimated coverage on the basis of guidance about campaign frequency, non-linear assumptions about the recovery of routine immunisation to pre-disruption magnitude, and 2030 endpoints informed by the WHO Immunization Agenda 2030 aims and expert consultation. We examined three main scenarios: no disruption, baseline recovery, and baseline recovery and catch-up. FINDINGS: We estimated that disruption to measles, rubella, HPV, hepatitis B, meningitis A, and yellow fever vaccination could lead to 49 119 additional deaths (95% credible interval [CrI] 17 248-134 941) during calendar years 2020-30, largely due to measles. For years of vaccination 2020-30 for all 14 pathogens, disruption could lead to a 2·66% (95% CrI 2·52-2·81) reduction in long-term effect from 37 378 194 deaths averted (34 450 249-40 241 202) to 36 410 559 deaths averted (33 515 397-39 241 799). We estimated that catch-up activities could avert 78·9% (40·4-151·4) of excess deaths between calendar years 2023 and 2030 (ie, 18 900 [7037-60 223] of 25 356 [9859-75 073]). INTERPRETATION: Our results highlight the importance of the timing of catch-up activities, considering estimated burden to improve vaccine coverage in affected cohorts. We estimated that mitigation measures for measles and yellow fever were particularly effective at reducing excess burden in the short term. Additionally, the high long-term effect of HPV vaccine as an important cervical-cancer prevention tool warrants continued immunisation efforts after disruption. FUNDING: The Vaccine Impact Modelling Consortium, funded by Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation. TRANSLATIONS: For the Arabic, Chinese, French, Portguese and Spanish translations of the abstract see Supplementary Materials section.


Asunto(s)
COVID-19 , Hepatitis B , Sarampión , Meningitis , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Rubéola (Sarampión Alemán) , Enfermedades Prevenibles por Vacunación , Fiebre Amarilla , Humanos , Infecciones por Papillomavirus/prevención & control , Pandemias , COVID-19/epidemiología , COVID-19/prevención & control , Vacunación , Inmunización , Hepatitis B/tratamiento farmacológico
7.
mSphere ; 9(2): e0067823, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38323845

RESUMEN

The ability of Aedes aegypti mosquitoes to transmit vertebrate pathogens depends on multiple factors, including the mosquitoes' life history traits, immune response, and microbiota (i.e., the microbes associated with the mosquito throughout its life). The microsporidium Edhazardia aedis is an obligate intracellular parasite that specifically infects Ae. aegypti mosquitoes and severely affects mosquito survival and other life history traits critical for pathogen transmission. In this work, we investigated how E. aedis impacts bacterial infection with Serratia marcescens in Ae. aegypti mosquitoes. We measured development, survival, and bacterial load in both larval and adult stages of mosquitoes. In larvae, E. aedis exposure was either horizontal or vertical and S. marcescens was introduced orally. Regardless of the route of transmission, E. aedis exposure resulted in significantly higher S. marcescens loads in larvae. E. aedis exposure also significantly reduced larval survival but subsequent exposure to S. marcescens had no effect. In adult females, E. aedis exposure was only horizontal and S. marcescens was introduced orally or via intrathoracic injection. In both cases, E. aedis infection significantly increased S. marcescens bacterial loads in adult female mosquitoes. In addition, females infected with E. aedis and subsequently injected with S. marcescens suffered 100% mortality which corresponded with a rapid increase in bacterial load. These findings suggest that exposure to E. aedis can influence the establishment and/or replication of other microbes in the mosquito. This has implications for understanding the ecology of mosquito immune defense and potentially disease transmission by mosquito vector species. IMPORTANCE: The microsporidium Edhazardia aedis is a parasite of the yellow fever mosquito, Aedes aegypti. This mosquito transmits multiple viruses to humans in the United States and around the world, including dengue, yellow fever, and Zika viruses. Hundreds of millions of people worldwide will become infected with one of these viruses each year. E. aedis infection significantly reduces the lifespan of Ae. aegypti and is therefore a promising novel biocontrol agent. Here, we show that when the mosquito is infected with this parasite, it is also significantly more susceptible to infection by an opportunistic bacterial pathogen, Serratia marcescens. This novel discovery suggests the mosquito's ability to control infection by other microbes is impacted by the presence of the parasite.


Asunto(s)
Aedes , Microsporidios , Parásitos , Fiebre Amarilla , Infección por el Virus Zika , Virus Zika , Animales , Femenino , Humanos , Estados Unidos , Larva/microbiología
8.
Exp Parasitol ; 259: 108708, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38325752

RESUMEN

The present reported work deals with the ability of Togolese plants' essential oils (EOs) to act as repellents for Aedes aegypti mosquitoes in order to use them as personal protective requirements or actions against mosquito bites and therefore to drastically reduce the risk of contracting dengue or yellow fever. EOs studied here were extracted from dry leaves of Ageratum conyzoides L., Eucalyptus citriodora Hook, and Lantana camara Linn, three plants that were collected at different daytimes (7 a.m., 1 p.m., and 7 p.m.) at various locations in Togo. Using a Clevenger-type device, EOs were obtained by the hydrodistillation method (Clevenger, 1928). The physical parameters of the EOs such as density, refractive index, rotatory power, and organoleptic properties were determined. Then, the characterization of EOs using gas chromatography equipped with a flame ionization detector (GC/FID) and gas chromatography coupled to mass spectrometry (GC/MS) was conducted. Chemical analyses showed the presence of several main compounds from EO samples of the three plants. The major compounds were characterized and identified as: (i) precocene I (67.7, 70.6, and 66.9%) and ß-caryophyllene (17.4, 12.1, and 16.5%) for the EO of A. conyzoïdes; (ii) citronellal (63.3, 67.2, and 75.4%) and citronellol (24.5, 21.4, and 14.3%) for E. citriodora and (iii) ß-caryophyllene (15.3, 11.7, and 12.4%), sabinene (28.4, 35, and 33.3%) and eucalyptol (11.5, 14.1, and 15.6%) for L. camara at 7 a.m., 1 p.m., and 7 p.m., respectively. The yield and the chemical composition of the oils vary according to harvesting time and sunlight. The insecticidal activity of EOs was evaluated following the CDC bottle method on Aedes aegypti females. All the EOs tested on the female adults of Aedes aegypti showed significant insecticidal activity. The EO of A. conyzoïdes at 1 p.m. and 7 p.m. resulted in 100% mortality after 8 min of exposure time at the lowest concentration (0.0025%). At the same concentration for the EO of E. citriodora, the mortality rates were 83%, 38.8%, and 30.80% at 7 a.m., 1 p.m., and 7 p.m., respectively for an exposure time of 8 min. The EO extracted from the leaves of L. camara harvested at 7 a.m. was effective after an exposure time of 15 min for a concentration of 0.02%. For the same concentration, the mortality rates of the EO of L. camara harvested at 1 p.m. and 7 p.m., after 8 min were 62.9% and 52%, respectively. From these interesting results reported for the first time in Togo, EOs from leaves of three Togolese plants harvested at different times of the day appear to be a valuable alternative for mosquito vector control in Togo or abroad countries in which dengue and yellow fever constitute a terrible scourge.


Asunto(s)
Aedes , Dengue , Insecticidas , Aceites Volátiles , Sesquiterpenos Policíclicos , Fiebre Amarilla , Humanos , Animales , Femenino , Aceites Volátiles/farmacología , Aceites Volátiles/química , Insecticidas/farmacología , Insecticidas/química , Cromatografía de Gases y Espectrometría de Masas , Dengue/prevención & control
9.
PLoS One ; 19(2): e0298723, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38346054

RESUMEN

BACKGROUND: Febrile jaundice is a common indicator of certain infectious diseases, including hepatitis E. In Cameroon, the yellow fever virus is the only pathogen that is monitored in patients who present with this symptom. However, more than 90% of the samples received as part of this surveillance are negative for yellow fever. This study aimed to describe the prevalence and hepatitis E virus (HEV) genotype among yellow fever-negative patients in the Far North and West regions of Cameroon. METHODS: In a cross-sectional study, yellow fever surveillance-negative samples collected between January 2021 and January 2023 were retrospectively analyzed. Anti-HEV IgM and IgG antibodies were tested using commercially available ELISA kits. Anti-HEV IgM and/or IgG positive samples were tested for HEV RNA by real-time RT-PCR, followed by nested RT-PCR, sequencing and phylogenetic analysis. RESULTS: Overall, 121 of the 543 samples (22.3%, 95% CI: 19.0% - 26.0%) were positive for at least one anti-HEV marker. Amongst these, 8.1% (44/543) were positive for anti-HEV IgM, 5.9% (32/543) for anti-HEV IgG, and 8.3% (45/544) for both markers. A total of 15.2% (12/79) samples were positive for HEV RNA real-time RT-PCR and 8 samples were positive for HEV RNA by nested RT-PCR. Phylogenetic analysis showed that the retrieved sequences clustered within HEV genotypes/subtypes 1/1e, 3/3f and 4/4b. CONCLUSION: Our results showed that HEV is one of the causes of acute febrile jaundice in patients enrolled in the yellow fever surveillance program in two regions of Cameroon. We described the circulation of three HEV genotypes, including two zoonotic genotypes. Further studies will be important to elucidate the transmission routes of these zoonotic HEV genotypes to humans in Cameroon.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Ictericia , Fiebre Amarilla , Humanos , Hepatitis E/complicaciones , Hepatitis E/epidemiología , Hepatitis E/diagnóstico , Estudios Retrospectivos , Camerún/epidemiología , Filogenia , Estudios Transversales , Anticuerpos Antihepatitis/genética , ARN Viral/genética , Ictericia/epidemiología , Ictericia/etiología , Inmunoglobulina M/genética , Genotipo , Inmunoglobulina G/genética
10.
Sci Rep ; 14(1): 3659, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38351076

RESUMEN

Temperature is a major ecological driver of mosquito-borne diseases as it influences the life-history of both the mosquito and the pathogen harboured within it. Understanding the mosquitoes' thermal biology is essential to inform risk prediction models of such diseases. Mosquitoes can respond to temperatures by microhabitat selection through thermal preference. However, it has not yet been considered that mosquitoes are likely to adapt to changing temperatures, for example during climate change, and alter their preference over evolutionary time. We investigated this by rearing six cohorts of the yellow fever mosquito Aedes aegypti at two temperatures (24 °C, 30 °C) for 20 generations and used these cohorts to explicitly separate the effects of long-term evolution and within-generation acclimation on their thermal preferences in a thermal gradient of 20-35 °C. We found that warm-evolved mosquitoes spent 31.5% less time at high temperatures, which affects their efficiency as a vector. This study reveals the complex interplay of experimental evolution, rearing temperatures, and thermal preference in Ae. aegypti mosquitoes. It highlights the significance of incorporating mosquito microhabitat selection in disease transmission models, especially in the context of climate change.


Asunto(s)
Aedes , Fiebre Amarilla , Animales , Temperatura , Mosquitos Vectores , Aedes/fisiología , Cambio Climático
11.
Nat Commun ; 15(1): 1236, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336944

RESUMEN

The mosquito-borne disease, Yellow fever (YF), has been largely controlled via mass delivery of an effective vaccine and mosquito control interventions. However, there are warning signs that YF is re-emerging in both Sub-Saharan Africa and South America. Imported from Africa in slave ships, YF was responsible for devastating outbreaks in the Caribbean. In Martinique, the last YF outbreak was reported in 1908 and the mosquito Aedes aegypti was incriminated as the main vector. We evaluated the vector competence of fifteen Ae. aegypti populations for five YFV genotypes (Bolivia, Ghana, Nigeria, Sudan, and Uganda). Here we show that mosquito populations from the Caribbean and the Americas were able to transmit the five YFV genotypes, with YFV strains for Uganda and Bolivia having higher transmission success. We also observed that Ae. aegypti populations from Martinique were more susceptible to YFV infection than other populations from neighboring Caribbean islands, as well as North and South America. Our vector competence data suggest that the threat of re-emergence of YF in Martinique and the subsequent spread to Caribbean nations and beyond is plausible.


Asunto(s)
Aedes , Fiebre Amarilla , Animales , Humanos , Virus de la Fiebre Amarilla/genética , Mosquitos Vectores , Indias Occidentales , Región del Caribe/epidemiología , Uganda
13.
Braz J Infect Dis ; 28(1): 103719, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38341187

RESUMEN

BACKGROUND: Safety data on the yellow fever vaccine 17DD in People Living with HIV (PLWH) are limited. This study explored the occurrence of post-vaccination 17DD viremia and the kinetics of hematological and liver laboratorial parameters in PLWH and HIV-uninfected participants [HIV(-) controls]. METHODS: We conducted a secondary analysis of a longitudinal interventional trial (NCT03132311) study that enrolled PLWH and HIV(-) controls to receive a single 17DD dose and were followed at 5, 30 and 365 days after vaccination in Rio de Janeiro, Brazil. 17DD viremia (obtained throughreal-time PCR and plaque forming units' assays), hematological (neutrophils, lymphocytes and platelets counts) and liver enzymes (ALT and AST) results were assessed at baseline and Days 5 and 30 post-vaccination. Logistic regression models explored factors associated with the odds of having positive 17DD viremia. Linear regression models explored variables associated with hematological and liver enzymes results at Day 5. RESULTS: A total of 202 PLWH with CD4 ≥ 200 cells/µL and 68 HIV(-) controls were included in the analyses. 17DD viremia was found in 20.0 % of the participants and was twice more frequent in PLWH than in HIV(-) controls (22.8% vs. 11.8 %, p-value < 0.001). Neutrophils, lymphocytes and platelets counts dropped at Day 5 and returned to baseline values at Day 30. 17DD viremia was associated with lower nadir of lymphocytes and platelets at Day 5. ALT levels did not increase post-vaccination and were not associated with 17DD viremia. CONCLUSIONS: 17DD was safe and well-tolerated in PLWH with CD4 ≥ 200 cells/µL. Post-vaccination viremia was more frequent in PLWH than in controls. Transient and self-limited decreases in lymphocytes and neutrophils occurred early after vaccination. 17DD viremia was associated with lower lymphocytes and platelets nadir after vaccination. We did not observe elevations in ALT after 17DD vaccination.


Asunto(s)
Infecciones por VIH , Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Humanos , Vacuna contra la Fiebre Amarilla/efectos adversos , Fiebre Amarilla/prevención & control , Estudios Longitudinales , Viremia , Anticuerpos Antivirales , Brasil , Vacunación/métodos , Hígado
14.
AMA J Ethics ; 26(2): E179-183, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38306208

RESUMEN

At the turn of the 20th century, the physician William Gorgas led work that substantially mitigated mortality from mosquito-borne diseases among workers building the Panama Canal. The waterway launched the United States to political and economic superpower status by eliminating the need for risky maritime travel around the southern tip of South America, expediting exportation of US goods in international markets. Yet, as this article explains, innovations that curbed malaria and yellow fever were deeply rooted in racist foundations of capital and empire.


Asunto(s)
Malaria , Racismo , Medicina Tropical , Fiebre Amarilla , Animales , Estados Unidos , Humanos , Panamá , Fiebre Amarilla/historia , Malaria/historia
15.
Brasília, D.F.; OPAS; 2024-01-12. (OPAS/BRA/FGL/24-0001).
No convencional en Portugués | PAHO-IRIS | ID: phr2-59165

RESUMEN

O presente documento denota o Relatório Técnico de Gestão de Imunização do Brasil, referente ao ano de 2022 – Relatório Anual Brasil 2022, no contexto da Estratégia de Cooperação do País 2022-2027 (ECP/2022-2027), promovida pelo escritório da OPAS/OMS no Brasil, e Ministério da Saúde do Brasil, como uma oportunidade de reforçar os compromissos e as alianças a fim de enfrentar os grandes desafios existentes no campo da saúde pública, especificamente na imunização e, com isso contribuir com os objetivos de recuperação das coberturas vacinais, ao longo do curso de vida. A Coordenação de Imunização da OPAS/OMS no Brasil executou ações dos componentes do Programa Nacional de Imunizações (PNI) em cooperação com o Brasil nas cinco prioridades estratégicas e áreas de foco definidas na ECP/2022-2027: 1) proteger e promover a saúde da população, centrada nas pessoas, famílias e comunidades, especialmente aquelas em situação de vulnerabilidade; 2) recuperar, melhorar e tornar mais forte os serviços de saúde e os programas prioritários impactados pela pandemia da covid-19; 3) contribuir para o desenvolvimento de um Sistema Único de Saúde (SUS) mais resiliente, equitativo e eficaz, de acordo com as necessidades de saúde da população; 4) impulsionar a pesquisa, a inovação e a geração de conhecimentos científicos e tecnológicos em saúde, incluindo aqueles voltados à pesquisa, ao desenvolvimento e à produção de medicamentos, fitoterápicos e produtos tradicionais em saúde, vacinas, biotecnológicos e tecnologias em saúde e 5) reforçar a prevenção, a preparação, a resposta oportuna e a recuperação nas emergências e nos desastres. Neste documento, será apresentada uma análise retrospectiva da situação epidemiológica das doenças preveníveis por vacinação, das estratégias de vacinação, dos riscos e impactos para 2023, bem como dos Eventos Supostamente Atribuíveis à Vacinação ou Imunização (ESAVI). Ainda, será exibido no documento a participação da OPAS/OMS Brasil na elaboração das propostas de melhorias e avanços para o PNI do Brasil e contribuições com os gestores do SUS e outros parceiros que atuam ativamente nesse propósito.


Asunto(s)
Inmunización , Vacunas , Vacunación , Sarampión , Poliomielitis , Fiebre Amarilla , COVID-19 , Gripe Humana , Cooperación Técnica , Brasil
17.
Lancet Glob Health ; 12(3): e445-e456, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38272044

RESUMEN

BACKGROUND: Long-term immunity following yellow fever vaccination remains controversial. We aimed to summarise the literature regarding the long-term protection (≥10 years) conveyed by a single dose of yellow fever vaccination. METHODS: In this systematic review and meta-analysis, we searched 11 databases from database inception to Aug 24, 2023. We included cohort and cross-sectional studies reporting immunogenicity outcomes for children or adults who received a single dose of yellow fever vaccination 10 or more years ago. Case series and single case reports were excluded. Participants who received more than one dose of yellow fever vaccination before measurement of the outcome were excluded. Identified records were reviewed by two independent reviewers. The primary outcome of the meta-analysis was the pooled seroprotection rate. Risk of bias was assessed with the Risk Of Bias In Non-randomized Studies of Interventions tool, and the Joanna Briggs Institute tool for analytical cross-sectional studies. Studies of moderate or good quality that reported seroprotection were included for random-effects meta-analysis and stratified by endemicity and specific risk groups. The study was registered with PROSPERO, CRD42023384087. FINDINGS: Of the 7363 articles identified by our search, 39 were eligible for inclusion for systematic review. These studies comprised 2895 individuals vaccinated 10-60 years ago. 20 studies were included in the meta-analysis. Pooled seroprotection rates were 94% (95% CI 86-99) among healthy adults in a non-endemic setting (mostly travellers) and 76% (65-85) in an endemic setting (all Brazilian studies). The pooled seroprotection rate was 47% (35-60) in children (aged 9-23 months at time of vaccination) and 61% (38-82) in people living with HIV. Reported criteria for seroprotection were highly heterogeneous. INTERPRETATION: The gathered evidence suggests that a single dose of yellow fever vaccination provides lifelong protection in travellers. However, in people living with HIV and children (younger than 2 years), booster doses might still be required because lower proportions of vaccinees were seroprotected 10 or more years post-vaccination. Lower observed seroprotection rates among residents of endemic areas were partly explained by the use of a higher cutoff for seroprotection that was applied in Brazil. Studies from sub-Saharan Africa were scarce and of low quality; thus no conclusions could be drawn for this region. FUNDING: None.


Asunto(s)
Infecciones por VIH , Fiebre Amarilla , Niño , Adulto , Humanos , Fiebre Amarilla/prevención & control , Estudios Transversales , Vacunación , Factores de Tiempo
19.
Future Med Chem ; 16(4): 295-310, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38288568

RESUMEN

Background: A vaccine or antiviral drug for respiratory syncytial virus (RSV) infections and a specific antiviral drug for yellow fever virus (YFV) infections has not yet been developed. Method: In this study, 2-indolinone-based N-(4-sulfamoylphenyl)hydrazinecarbothioamides were synthesized. Along with these new compounds, previously synthesized 2-indolinone-based N-(3-sulfamoylphenyl)hydrazinecarbothioamides were evaluated against various DNA and RNA viruses. Results: Some 2-indolinone compounds exhibited nontoxic and selective antiviral activities against RSV and YFV. Halogen substitution at the indole ring increased the anti-RSV activities. Moreover, 1-benzyl and 5-halogen or nitro-substituted compounds were the most effective compounds against YFV. Conclusion: Generally, the 3-sulfonamide-substituted compounds were determined to be more effective than 4-sulfonamide-substituted compounds against RSV and YFV.


Asunto(s)
Fiebre Amarilla , Virus de la Fiebre Amarilla , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Halógenos , Sulfonamidas/farmacología , Fiebre Amarilla/tratamiento farmacológico , Indoles/química , Indoles/farmacología
20.
Acta Trop ; 251: 107110, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38163515

RESUMEN

Yellow Fever (YF) is a viral arbovirosis of Public Health importance. In Brazil, surveillance is focused mainly on detecting epizootic events of Platyrrhini. Herein, we compared the detection and phylogenetic analysis of YF virus in two neotropical primates (NTP), a Callithrix detected in the previous epidemic period (2016-2020), and a Callicebus nigrifons, showing a new introduction of YF in 2023. This paper illustrates the importance of joint actions of laboratory and field teams to ensure quick response to Public Health emergencies, such as the intensification of vaccination of susceptible human populations.


Asunto(s)
Fiebre Amarilla , Virus de la Fiebre Amarilla , Animales , Humanos , Virus de la Fiebre Amarilla/genética , Filogenia , Brasil/epidemiología , Fiebre Amarilla/epidemiología , Fiebre Amarilla/prevención & control , Callithrix , Brotes de Enfermedades
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