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1.
Artículo en Inglés | MEDLINE | ID: mdl-33656136

RESUMEN

This observational retrospective study conducted during an yellow fever (YF) outbreak in Sao Paulo, Brazil, in 2017-2018, describes adverse events (AE) following YF vaccination of immunocompromised persons. Risks and benefits of vaccination were individually evaluated by physicians. AE were assessed by phone call or electronic mail, 14 to 90 days after vaccination. Three hundred and eighty one immunocompromised persons received a full-dose of YF vaccine. Their age ranged from 1.4 to 89.3 years (median 50.8 years); 53% were women; 178 (46.7%) had chronic kidney disease, 78 (20.5%) had immune-mediated inflammatory diseases; 94 (24.7%) were using or had recently used immunosuppressive/ immunomodulatory drugs. All of them denied previous YF vaccination. We were able to contact 341 (89.5%) vaccinees: 233 (68.3%) of them received the YF vaccine from BioManguinhos and 108 (31.7%) received the vaccine from Sanofi-Pasteur; 130 (38.1%) vaccinees received other vaccines (up to 4) simultaneously with the the YF vaccine, mostly hepatitis B (59 vaccinees), pneumococcal polysaccharide 23-valent (46), influenza (43) and diphtheria-tetanus (dT, 41). One hundred and eleven vaccinees (32.6%) reported at least one AE: 79 (23.2%) presented systemic AE, 44 (12.9%) had local AE and 12 had both, local and systemic AE. The most common AE was pain at the injection site (41 persons, 12%), myalgia (34; 10%), fever (25; 7.3%) and headache (16; 4.7%). There was no statistically significant difference on the AE frequency according to the vaccine producer. There were four severe AE: one hospitalization and three deaths, considered not related to the YF vaccine.


Asunto(s)
Huésped Inmunocomprometido , Vacunación/efectos adversos , Vacuna contra la Fiebre Amarilla/efectos adversos , Fiebre Amarilla/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/complicaciones , Estudios Retrospectivos , Fiebre Amarilla/epidemiología , Vacuna contra la Fiebre Amarilla/administración & dosificación , Adulto Joven
3.
Mem Inst Oswaldo Cruz ; 115: e200278, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33566939

RESUMEN

BACKGROUND: The impact of arbovirus cocirculation in Brazil is unknown. Dengue virus (DENV) reinfection may result in more intense viraemia or immunopathology, leading to more severe disease. The Zika virus (ZIKV) epidemic in the Americas provided pathogenicity evidence that had not been previously observed in flavivirus infections. In contrast to other flaviviruses, electron microscopy studies have shown that ZIKV may replicate in viroplasm-like structures. Flaviviruses produce an ensemble of structurally different virions, collectively contributing to tissue tropism and virus dissemination. OBJECTIVES AND METHODS: In this work, the Aedes albopictus mosquito cell lineage (C6/36 cells) and kidney epithelial cells from African green monkeys (Vero cells) were infected with samples of the main circulating arboviruses in Brazil [DENV-1, DENV-2, DENV-3, DENV-4, ZIKV, Yellow Fever virus (YFV) and Chikungunya virus (CHIKV)], and ultrastructural studies by transmission electron microscopy were performed. FINDINGS: We observed that ZIKV, the DENV serotypes, YFV and CHIKV particles are spherical. ZIKV, DENV-1, -2, -3 and -4 presented diameters of 40-50 nm, and CHIKV presented approximate diameters of 50-60 nm. Viroplasm-like structures was observed in ZIKV replication cycle. MAIN CONCLUSIONS: The morphogenesis of these arboviruses is similar to what has been presented in previous studies. However, we understand that further studies are needed to investigate the relationship between viroplasm-like structures and ZIKV replication dynamics.


Asunto(s)
Arbovirus , Fiebre Chikungunya , Dengue , Epidemias , Fiebre Amarilla , Infección por el Virus Zika , Virus Zika , Animales , Brasil/epidemiología , Fiebre Chikungunya/epidemiología , Chlorocebus aethiops , Dengue/epidemiología , Células Vero , Infección por el Virus Zika/epidemiología
4.
Viruses ; 13(1)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445752

RESUMEN

The yellow fever vaccine (YF17DD) is highly effective with a single injection conferring protection for at least 10 years. The YF17DD induces polyvalent responses, with a TH1/TH2 CD4+ profile, robust T CD8+ responses, and synthesis of interferon-gamma (IFN-γ), culminating in high titers of neutralizing antibodies. Furthermore, C-type lectin domain containing 5A (CLEC5A) has been implicated in innate outcomes in other flaviviral infections. Here, we conducted a follow-up study in volunteers immunized with YF17DD, investigating the humoral response, cellular phenotypes, gene expression, and single nucleotide polymorphisms (SNPs) of IFNG and CLEC5A, to clarify the role of these factors in early response after vaccination. Activation of CLEC5A+ monocytes occurred five days after vaccination (DAV). Following, seven DAV data showed activation of CD4+ and CD8+T cells together with early positive correlations between type II IFN and genes of innate antiviral response (STAT1, STAT2, IRF7, IRF9, OAS1, and RNASEL) as well as antibody levels. Furthermore, individuals with genotypes rs2430561 AT/AA, rs2069718 AG/AA (IFNG), and rs13237944 AC/AA (CLEC5A), exhibited higher expression of IFNG and CLEC5A, respectively. Together, we demonstrated that early IFN-γ and CLEC5A responses, associated with rs2430561, rs2069718, and rs13237944 genotypes, may be key mechanisms in the long-lasting immunity elicited by YF17DD.


Asunto(s)
Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Inmunidad , Interferón gamma/metabolismo , Lectinas Tipo C/genética , Receptores de Superficie Celular/genética , Vacunación , Vacuna contra la Fiebre Amarilla/inmunología , Fiebre Amarilla/etiología , Fiebre Amarilla/prevención & control , Adulto , Animales , Femenino , Humanos , Inmunogenicidad Vacunal , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Linfocitos T/inmunología , Linfocitos T/metabolismo , Adulto Joven
5.
Rev Soc Bras Med Trop ; 53: e20200787, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33331614

RESUMEN

INTRODUCTION: Since 2016, Brazil has been in the midst of its largest sylvatic yellow fever epidemic ever, found predominantly outside the Amazon region. Cases originating from Brazil have been reported in France, the Netherlands, Romania, Switzerland, Argentina, and Chile. The epidemic began in the Central-West region of Brazil in 2014, spreading into the Southern region, with significant non-human primate transmission continuing towards Paraguay and Argentina. METHODS: This report is an integrative review of Pan American Health Organization cooperation during a sylvatic yellow fever epidemic. RESULTS: The Pan American Health Organization has played a central role in handling the yellow fever emergency, collaborating with the Ministry of Health and various research groups in supporting interventions of different response areas. The Pan American Health Organization's technical cooperation included: training and workshops to exchange experiences, carrying out technical cooperation in patient management and epidemiological, entomological, laboratory, and epizootic surveillance, organizing the assistance network, and acquiring strategic inputs. The Pan American Health Organization's technical cooperation supported the Ministry of Health's decision to adopt a single-dose vaccine and use fractional doses to support the vaccination needs of more than 39,000,000 people. The coronavirus disease 2019 pandemic contributed to the failure of reaching the yellow fever vaccination goals and made it difficult to integrate the yellow fever vaccine into recommended areas. CONCLUSIONS: Given the ongoing coronavirus disease 2019 pandemic, it is necessary to strengthen measures for the surveillance, prevention, and control of yellow fever with multilateral cooperation between countries.


Asunto(s)
Fiebre Amarilla , Argentina , Brasil , Brotes de Enfermedades , Francia , Humanos , Organización Panamericana de la Salud , Pandemias , Paraguay , Fiebre Amarilla/epidemiología , Fiebre Amarilla/prevención & control , Virus de la Fiebre Amarilla
6.
BMC Bioinformatics ; 21(Suppl 17): 551, 2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33308151

RESUMEN

BACKGROUND: An effective yellow fever (YF) vaccine has been available since 1937. Nevertheless, questions regarding its use remain poorly understood, such as the ideal dose to confer immunity against the disease, the need for a booster dose, the optimal immunisation schedule for immunocompetent, immunosuppressed, and pediatric populations, among other issues. This work aims to demonstrate that computational tools can be used to simulate different scenarios regarding YF vaccination and the immune response of individuals to this vaccine, thus assisting the response of some of these open questions. RESULTS: This work presents the computational results obtained by a mathematical model of the human immune response to vaccination against YF. Five scenarios were simulated: primovaccination in adults and children, booster dose in adult individuals, vaccination of individuals with autoimmune diseases under immunomodulatory therapy, and the immune response to different vaccine doses. Where data were available, the model was able to quantitatively replicate the levels of antibodies obtained experimentally. In addition, for those scenarios where data were not available, it was possible to qualitatively reproduce the immune response behaviours described in the literature. CONCLUSIONS: Our simulations show that the minimum dose to confer immunity against YF is half of the reference dose. The results also suggest that immunological immaturity in children limits the induction and persistence of long-lived plasma cells are related to the antibody decay observed experimentally. Finally, the decay observed in the antibody level after ten years suggests that a booster dose is necessary to keep immunity against YF.


Asunto(s)
Modelos Teóricos , Vacuna contra la Fiebre Amarilla/inmunología , Fiebre Amarilla/prevención & control , Adulto , Anticuerpos Neutralizantes/sangre , Niño , Humanos , Sistema Inmunológico , Inmunización Secundaria , Huésped Inmunocomprometido , Vacunación , Fiebre Amarilla/inmunología
7.
Nat Commun ; 11(1): 5801, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-33199712

RESUMEN

Historically endemic to Sub-Saharan Africa and South America, yellow fever is absent from the Asia-Pacific region. Yellow fever virus (YFV) is mainly transmitted by the anthropophilic Aedes mosquitoes whose distribution encompasses a large belt of tropical and sub tropical regions. Increasing exchanges between Africa and Asia have caused imported YFV incidents in non-endemic areas, which are threatening Asia with a new viral emergence. Here, using experimental infections of field-collected mosquitoes, we show that Asian-Pacific Aedes mosquitoes are competent vectors for YFV. We observe that Aedes aegypti populations from Singapore, Taiwan, Thailand, and New Caledonia are capable of transmitting YFV 14 days after oral infections, with a number of viral particles excreted from saliva reaching up to 23,000 viral particles. These findings represent the most comprehensive assessment of vector competence and show that Ae. aegypti mosquitoes from the Asia-Pacific region are highly competent to YFV, corroborating that vector populations are seemingly not a brake to the emergence of yellow fever in the region.


Asunto(s)
Fiebre Amarilla/transmisión , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/fisiología , Aedes/virología , Animales , Asia/epidemiología , Geografía , Insectos Vectores/virología , Modelos Lineales , Probabilidad , Factores de Riesgo , Saliva/virología , Carga Viral
8.
Goiânia; SES-GO; 26 out. 2020. 1-5 p. tab, graf.
No convencional en Portugués | LILACS, Coleciona SUS, CONASS, SES-GO | ID: biblio-1141389

RESUMEN

A febre amarela é uma doença febril aguda de curta duração (no máximo 12 dias) e de gravidade variável. Apesar da erradicação da febre amarela urbana no Brasil, a febre amarela silvestre é endêmica em nosso país devido à manutenção do vírus na natureza, pela transmissão entre primatas não humanos (PNH) e mosquitos silvestres arbóreos. Acidentalmente, seres humanos susceptíveis são infectados ao penetrar o ciclo enzoótico natural. Por isso é importante atenção aos "eventos sentinela", situações em que um número maior de PNH adoece e morre alertando a comunidade na forma de epizootia. Nessa situação definem-se estratégias de intensificação da vacinação nos moradores das regiões afetadas (BRASIL, 2018).


Yellow fever is a short-term acute febrile disease (maximum 12 days) and of varying severity. Despite the eradication of urban yellow fever in Brazil, wild yellow fever is endemic in our country due to the maintenance of the virus in nature, due to the transmission between non-human primates (NHP) and wild tree mosquitoes. Accidentally, susceptible humans are infected by penetrating the natural enzootic cycle. Therefore, it is important to pay attention to "sentinel events", situations in which a greater number of NHP gets sick and dies alerting the community in the form of epizootics. This situation defines strategies for intensifying vaccination in residents of the affected regions (BRASIL, 2018).


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Fiebre Amarilla/prevención & control , Fiebre Amarilla/terapia
9.
PLoS Negl Trop Dis ; 14(9): e0008711, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32997666

RESUMEN

Environmental enteric dysfunction (EED) is an intestinal disorder common among children in low-resource settings and is associated with increased risk of growth stunting, cognitive deficits, and reduced oral vaccine immunogenicity. The Micronutrient and EED Assessment Tool (MEEDAT) is a multiplexed immunoassay that measures biomarkers previously associated with child growth faltering and/or oral vaccine immunogenicity: intestinal fatty acid-binding protein (I-FABP), soluble CD14 (sCD14), insulin-like growth factor 1 (IGF-1), and fibroblast growth factor 21 (FGF21). MEEDAT also measures systemic inflammation (α1-acid glycoprotein, C-reactive protein), ferritin, soluble transferrin receptor, retinol binding protein 4, thyroglobulin, and Plasmodium falciparum antigenemia (histidine-rich protein 2). The performance of MEEDAT was compared with commercially available enzyme-linked immunosorbent assays (ELISAs) using 300 specimens from Malian infant clinical trial participants. Regression methods were used to test if MEEDAT biomarkers were associated with seroconversion to meningococcal A conjugate vaccine (MenAV), yellow fever vaccine (YFV), and pentavalent rotavirus vaccine (PRV) after 28 days, or with growth faltering over 12 weeks. The Pearson correlations between the MEEDAT and ELISA results were 0.97, 0.86, 0.80, and 0.97 for serum I-FABP, sCD14, IGF-1, and FGF21, respectively. There were significant associations between I-FABP concentration and the probability of PRV IgG seroconversion and between IGF-1 concentration and the probability of YFV seroconversion. In multivariable models neither association remained significant, however there was a significant negative association between AGP concentration and YFV seroconversion. GLP-2 and sCD14 concentrations were significantly negatively associated with 12-week change in weight-for-age z-score and weight-for-height z-score in multivariable models. MEEDAT performed well in comparison to commercially-available ELISAs for the measurement of four analytes for EED and growth hormone resistance. Adoption of MEEDAT in low-resource settings could help accelerate the identification of interventions that prevent or treat child stunting and interventions that boost the immunogenicity of child vaccinations.


Asunto(s)
Inmunogenicidad Vacunal/inmunología , Enfermedades Intestinales/inmunología , Micronutrientes/inmunología , Vacunas/inmunología , Vacuna contra la Fiebre Amarilla/inmunología , Fiebre Amarilla/inmunología , Fiebre Amarilla/prevención & control , Biomarcadores/sangre , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Proteínas de Unión a Ácidos Grasos , Femenino , Ferritinas/sangre , Factores de Crecimiento de Fibroblastos/sangre , Humanos , Lactante , Inflamación , Factor I del Crecimiento Similar a la Insulina/metabolismo , Intestino Delgado , Receptores de Lipopolisacáridos , Masculino , Malí , Proteínas Plasmáticas de Unión al Retinol , Factores de Riesgo , Vacunación
10.
Front Immunol ; 11: 1836, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32983097

RESUMEN

Examining CD8+ and CD4+ T cell responses after primary Yellow Fever vaccination in a cohort of 210 volunteers, we have identified and tetramer-validated 92 CD8+ and 50 CD4+ T cell epitopes, many inducing strong and prevalent (i.e., immunodominant) T cell responses. Restricted by 40 and 14 HLA-class I and II allotypes, respectively, these responses have wide population coverage and might be of considerable academic, diagnostic and therapeutic interest. The broad coverage of epitopes and HLA overcame the otherwise confounding effects of HLA diversity and non-HLA background providing the first evidence of T cell immunodomination in humans. Also, double-staining of CD4+ T cells with tetramers representing the same HLA-binding core, albeit with different flanking regions, demonstrated an extensive diversification of the specificities of many CD4+ T cell responses. We suggest that this could reduce the risk of pathogen escape, and that multi-tetramer staining is required to reveal the true magnitude and diversity of CD4+ T cell responses. Our T cell epitope discovery approach uses a combination of (1) overlapping peptides representing the entire Yellow Fever virus proteome to search for peptides containing CD4+ and/or CD8+ T cell epitopes, (2) predictors of peptide-HLA binding to suggest epitopes and their restricting HLA allotypes, (3) generation of peptide-HLA tetramers to identify T cell epitopes, and (4) analysis of ex vivo T cell responses to validate the same. This approach is systematic, exhaustive, and can be done in any individual of any HLA haplotype. It is all-inclusive in the sense that it includes all protein antigens and peptide epitopes, and encompasses both CD4+ and CD8+ T cell epitopes. It is efficient and, importantly, reduces the false discovery rate. The unbiased nature of the T cell epitope discovery approach presented here should support the refinement of future peptide-HLA class I and II predictors and tetramer technologies, which eventually should cover all HLA class I and II isotypes. We believe that future investigations of emerging pathogens (e.g., SARS-CoV-2) should include population-wide T cell epitope discovery using blood samples from patients, convalescents and/or long-term survivors, who might all hold important information on T cell epitopes and responses.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Vacunación , Vacuna contra la Fiebre Amarilla/inmunología , Fiebre Amarilla/prevención & control , Virus de la Fiebre Amarilla/inmunología , Betacoronavirus/inmunología , Estudios de Cohortes , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/virología , Voluntarios Sanos , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos , Inmunogenicidad Vacunal , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/virología , Fiebre Amarilla/virología
11.
PLoS Negl Trop Dis ; 14(9): e0008549, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32881913

RESUMEN

BACKGROUND: Chikungunya (CHIK) and yellow fever (YF) are becoming major public health threats in East African countries including Ethiopia. In Ethiopia, there is no reliable information about the epidemiology of CHIK. This study aimed to assess a community-based sero-prevalence of CHIK and YF in the South Omo Valley, an endemic area for YF. METHODS: Between February and June 2018, blood samples were collected from study participants and screened for IgG antibody against CHIK virus (CHIKV) and YF virus (YFV) infections using ELISA. Data were computerized using Epi Data Software v.3.1 and analyzed using SPSS. RESULTS: A total of 360 participants (51.7% males, age range from 6 to 80, mean age ± SD = 31.95 ± 14.05 years) participated in this study. The overall sero-prevalence of IgG antibody was 43.6% (157/360) against CHIKV, while it was 49.5% (155/313) against YFV. Out of 155 samples which were positive for IgG antibody to YFV, 93 (60.0%) were positive for IgG antibody to CHIKV. Out of 158 samples which were negative for IgG antibody to YFV, 64(40.5%) were positive for IgG antibody to CHIKV. There was a significant positive correlation between IgG antibodies to CHIKV and YFV (sr = 0.82; P<0.01). Residency in the Debub Ari district (AOR = 8.47; 95% CI: 1.50, 47.74) and travel history to sylvatic areas (AOR = 2.21; 95% CI: 1.02, 4.81) were significantly and positively associated with high sero-prevalence of IgG antibody to CHIKV and YFV, respectively. CONCLUSION: High sero-prevalence of IgG antibody to CHIKV shows the circulation of the virus in the present study area. A low sero-prevalence of IgG antibody to YFV in YF vaccine received individuals is highly concerning from a public health point of view as waning of immune response to YFV infection could result in a periodic outbreaks of YF in endemic areas.Nevertheless, the present study has not investigated for possible cross-reactivity of antibody to CHIKV with other alphaviruses like O'nyong-nyong virus and antibody to YFV with other flaviviruses like Dengue fever virus and this warrants further studies in the present study area.


Asunto(s)
Anticuerpos Antivirales/sangre , Fiebre Chikungunya/sangre , Fiebre Amarilla/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Virus Chikungunya/inmunología , Virus Chikungunya/aislamiento & purificación , Niño , Estudios Transversales , Etiopía/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Características de la Residencia , Estudios Seroepidemiológicos , Fiebre Amarilla/epidemiología , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/inmunología , Virus de la Fiebre Amarilla/aislamiento & purificación , Adulto Joven
12.
Rev Prat ; 70(3): 312-316, 2020 Mar.
Artículo en Francés | MEDLINE | ID: mdl-32877067

RESUMEN

Yellow fever is still a current threat? Yellow fever is a mosquito-borne disease. Africa is the major endemic zone, although there have been epidemics of concern in South America in the last 3 years, especially in Brazil. The virus causes a febrile hepatitis, which can lead to hemorrhagic complications and death. Diagnosis is based on non-specific serological tests. There is no curative treatment. Prevention relies on protection against mosquito bites and on vaccination with a live attenuated vaccine. WHO recommends only one dose of vaccine but data from the literature about life-long protection are divergent on that point, and travel medicine French authorities still recommend a second dose in most at-risk situations.


Asunto(s)
Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , África/epidemiología , Animales , América del Sur/epidemiología , Medicina del Viajero , Fiebre Amarilla/epidemiología , Fiebre Amarilla/prevención & control
13.
PLoS Negl Trop Dis ; 14(8): e0008405, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32780745

RESUMEN

Yellow fever virus (YFV) causes a clinical syndrome of acute hemorrhagic hepatitis. YFV transmission involves non-human primates (NHP), mosquitoes and humans. By late 2016, Brazil experienced the largest YFV outbreak of the last 100 years, with 2050 human confirmed cases, with 681 cases ending in death and 764 confirmed epizootic cases in NHP. Among affected areas, Bahia state in Northeastern was the only region with no autochthonous human cases. By using next generation sequence approach, we investigated the molecular epidemiology of YFV in NHP in Bahia and discuss what factors might have prevented human cases. We investigated 47 YFV positive tissue samples from NHP cases to generate 8 novel YFV genomes. ML phylogenetic tree reconstructions and automated subtyping tools placed the newly generated genomes within the South American genotype I (SA I). Our analysis revealed that the YFV genomes from Bahia formed two distinct well-supported phylogenetic clusters that emerged most likely of an introduction from Minas Gerais and Espírito Santo states. Vegetation coverage analysis performed shows predominantly low to medium vegetation coverage in Bahia state. Together, our findings support the hypothesis of two independent YFV SA-I introductions. We also highlighted the effectiveness of the actions taken by epidemiological surveillance team of the state to prevented human cases.


Asunto(s)
Enfermedades de los Primates/virología , Fiebre Amarilla/veterinaria , Virus de la Fiebre Amarilla/genética , Alouatta , Animales , Brasil/epidemiología , Callithrix , Ecosistema , Genoma Viral , Humanos , Filogenia , Fiebre Amarilla/epidemiología , Fiebre Amarilla/prevención & control , Fiebre Amarilla/transmisión , Virus de la Fiebre Amarilla/clasificación
14.
Mem Inst Oswaldo Cruz ; 115: e200284, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32785481

RESUMEN

The coronavirus disease of 2019 (COVID-19) pandemic challenges public health systems around the world. Tropical countries will face complex epidemiological scenarios involving the simultaneous transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with viruses transmitted by Aedes aegypti. The occurrence of arboviral diseases with COVID-19 in the Latin America and the Caribbean (LAC) region presents challenges and opportunities for strengthening health services, surveillance and control programs. Financing of training, equipment and reconversion of hospital spaces will have a negative effect on already the limited resource directed to the health sector. The strengthening of the diagnostic infrastructure reappears as an opportunity for the national reference laboratories. Sharing of epidemiological information for the modeling of epidemiological scenarios allows collaboration between health, academic and scientific institutions. The fear of contagion by COVID-19 is constraining people with arboviral diseases to search for care which can lead to an increase in serious cases and could disrupt the operation of vector-control programs due to the reluctance of residents to open their doors to health personnel. Promoting intense community participation along with the incorporation of long lasting innovations in vector control offers new opportunities for control. The COVID-19 pandemic offers challenges and opportunities that must provoke positive behavioral changes and encourage more permanent self-care actions.


Asunto(s)
Aedes/microbiología , Aedes/virología , Infecciones por Coronavirus , Coronavirus , Dengue/prevención & control , Pandemias , Neumonía Viral , Fiebre Amarilla/prevención & control , Américas , Animales , Betacoronavirus , Región del Caribe , Infecciones por Coronavirus/epidemiología , Humanos , Mosquitos Vectores , Neumonía Viral/epidemiología
15.
PLoS Pathog ; 16(8): e1008699, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32764827

RESUMEN

São Paulo, a densely inhabited state in southeast Brazil that contains the fourth most populated city in the world, recently experienced its largest yellow fever virus (YFV) outbreak in decades. YFV does not normally circulate extensively in São Paulo, so most people were unvaccinated when the outbreak began. Surveillance in non-human primates (NHPs) is important for determining the magnitude and geographic extent of an epizootic, thereby helping to evaluate the risk of YFV spillover to humans. Data from infected NHPs can give more accurate insights into YFV spread than when using data from human cases alone. To contextualise human cases, identify epizootic foci and uncover the rate and direction of YFV spread in São Paulo, we generated and analysed virus genomic data and epizootic case data from NHPs in São Paulo. We report the occurrence of three spatiotemporally distinct phases of the outbreak in São Paulo prior to February 2018. We generated 51 new virus genomes from YFV positive cases identified in 23 different municipalities in São Paulo, mostly sampled from NHPs between October 2016 and January 2018. Although we observe substantial heterogeneity in lineage dispersal velocities between phylogenetic branches, continuous phylogeographic analyses of generated YFV genomes suggest that YFV lineages spread in São Paulo at a mean rate of approximately 1km per day during all phases of the outbreak. Viral lineages from the first epizootic phase in northern São Paulo subsequently dispersed towards the south of the state to cause the second and third epizootic phases there. This alters our understanding of how YFV was introduced into the densely populated south of São Paulo state. Our results shed light on the sylvatic transmission of YFV in highly fragmented forested regions in São Paulo state and highlight the importance of continued surveillance of zoonotic pathogens in sentinel species.


Asunto(s)
Genoma Viral , Enfermedades de los Primates/virología , Fiebre Amarilla/veterinaria , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/genética , Zoonosis/virología , Animales , Brasil/epidemiología , Brotes de Enfermedades , Genómica , Humanos , Filogenia , Filogeografía , Enfermedades de los Primates/epidemiología , Enfermedades de los Primates/transmisión , Primates/virología , Fiebre Amarilla/epidemiología , Fiebre Amarilla/transmisión , Virus de la Fiebre Amarilla/clasificación , Virus de la Fiebre Amarilla/aislamiento & purificación , Zoonosis/epidemiología , Zoonosis/transmisión
17.
Mem Inst Oswaldo Cruz ; 115: e200218, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32696917

RESUMEN

BACKGROUND: Southeast Brazil has recently experienced a Yellow Fever virus (YFV) outbreak where the mosquito Haemagogus leucocelaenus was a primary vector. Climatic factors influence the abundance of mosquito vectors and arbovirus transmission. OBJECTIVES: We aimed at describing the population dynamics of Hg. leucocelaenus in a county touched by the recent YFV outbreak. METHODS: Fortnightly egg collections with ovitraps were performed from November 2012 to February 2017 in a forest in Nova Iguaçu, Rio de Janeiro, Brazil. The effects of mean temperature and rainfall on the Hg. leucocelaenus population dynamics were explored. FINDINGS: Hg. leucocelaenus eggs were continuously collected throughout the study, with a peak in the warmer months (December-March). The climatic variables had a time-lagged effect and four weeks before sampling was the best predictor for the positivity of ovitraps and total number of eggs collected. The probability of finding > 50% positive ovitraps increased when the mean temperature was above 24ºC. The number of Hg. leucocelaenus eggs expressively increase when the mean temperature and accumulated precipitation surpassed 27ºC and 100 mm, respectively, although the effect of rainfall was less pronounced. MAIN CONCLUSIONS: Monitoring population dynamics of Hg. leucocelaenus and climatic factors in YFV risk areas, especially mean temperature, may assist in developing climate-based surveillance procedures to timely strengthening prophylaxis and control.


Asunto(s)
Culicidae/virología , Bosques , Insectos Vectores/virología , Dinámica Poblacional , Fiebre Amarilla , Virus de la Fiebre Amarilla/aislamiento & purificación , Animales , Brasil , Culicidae/clasificación , Insectos Vectores/clasificación , Estaciones del Año , Temperatura , Virus de la Fiebre Amarilla/genética
18.
N Engl J Med ; 383(5): 452-459, 2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32726531

RESUMEN

BACKGROUND: Insufficient vaccine doses and the lack of therapeutic agents for yellow fever put global health at risk, should this virus emerge from sub-Saharan Africa and South America. METHODS: In phase 1a of this clinical trial, we assessed the safety, side-effect profile, and pharmacokinetics of TY014, a fully human IgG1 anti-yellow fever virus monoclonal antibody. In a double-blind, phase 1b clinical trial, we assessed the efficacy of TY014, as compared with placebo, in abrogating viremia related to the administration of live yellow fever vaccine (YF17D-204; Stamaril). The primary safety outcomes were adverse events reported 1 hour after the infusion and throughout the trial. The primary efficacy outcome was the dose of TY014 at which 100% of the participants tested negative for viremia within 48 hours after infusion. RESULTS: A total of 27 healthy participants were enrolled in phase 1a, and 10 participants in phase 1b. During phase 1a, TY014 dose escalation to a maximum of 20 mg per kilogram of body weight occurred in 22 participants. During phases 1a and 1b, adverse events within 1 hour after infusion occurred in 1 of 27 participants who received TY014 and in none of the 10 participants who received placebo. At least one adverse event occurred during the trial in 22 participants who received TY014 and in 8 who received placebo. The mean half-life of TY014 was approximately 12.8 days. At 48 hours after the infusion, none of the 5 participants who received the starting dose of TY014 of 2 mg per kilogram had detectable YF17D-204 viremia; these participants remained aviremic throughout the trial. Viremia was observed at 48 hours after the infusion in 2 of 5 participants who received placebo and at 72 hours in 2 more placebo recipients. Symptoms associated with yellow fever vaccine were less frequent in the TY014 group than in the placebo group. CONCLUSIONS: This phase 1 trial of TY014 did not identify worrisome safety signals and suggested potential clinical benefit, which requires further assessment in a phase 2 trial. (Funded by Tysana; ClinicalTrials.gov number, NCT03776786.).


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Vacuna contra la Fiebre Amarilla , Fiebre Amarilla/tratamiento farmacológico , Virus de la Fiebre Amarilla/inmunología , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/farmacocinética , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Semivida , Humanos , Estimación de Kaplan-Meier , Viremia/tratamiento farmacológico , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/efectos de los fármacos
20.
Artículo en Inglés | MEDLINE | ID: mdl-32491144

RESUMEN

Eleven lactating women were inadvertently vaccinated with 17DD yellow fever vaccine in a small city of Sao Paulo State, Brazil. Their infants were being exclusively breast-fed and the breastfeeding was interrupted for 10 days. Serum and breastmilk were collected from the vaccinated mothers and tested for the presence of genomic RNA of the vaccine strain 8, 10 and 15 days after vaccination. Viral RNA was not detected in any of the serum and human milk samples tested and the infants remained asymptomatic. Our result strengthens the effectineness of stopping breastfeeding for 10 days after the inadvertent yellow fever vaccination of lactating women.


Asunto(s)
Lactancia Materna/efectos adversos , Leche Humana/virología , Vacuna contra la Fiebre Amarilla/efectos adversos , Fiebre Amarilla/prevención & control , Virus de la Fiebre Amarilla/inmunología , Anticuerpos Antivirales/sangre , Antígenos Virales/sangre , Brasil , Femenino , Humanos , Recién Nacido , ARN Viral/sangre , Fiebre Amarilla/transmisión , Vacuna contra la Fiebre Amarilla/administración & dosificación
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