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1.
Recurso na Internet em Inglês, Espanhol | LIS - Localizador de Informação em Saúde, LIS-bvsms | ID: lis-LISBR1.1-47017

RESUMO

Los esfuerzos para garantizar que los países de America Latina y el Caribe estén preparados para llevar a cabo el diagnóstico de laboratorio para detectar la nueva enfermedad por el coronavirus 2019 (COVID-19) han continuado esta semana con una capacitación en la Ciudad de México, organizada por la Organización Panamericana de la Salud (OPS) y el Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE) de la Secretaría de Salud de México.


Assuntos
Infecções por Coronavirus/diagnóstico , Capacitação Profissional , Vírus da SARS , Américas/epidemiologia
2.
; OPS/OMS.
Recurso na Internet em Inglês, Espanhol | LIS - Localizador de Informação em Saúde | ID: lis-LISBR1.1-46954

RESUMO

La Directora de la Organización Panamericana de la Salud (OPS), Carissa Etienne, instó hoy a los países de la región de las Américas a estar preparados para detectar tempranamente, aislar y cuidar a pacientes infectados con el nuevo coronavirus, ante la posibilidad de recibir viajeros provenientes de países donde hay transmisión del virus.


Assuntos
Infecções por Coronavirus , Américas
3.
Oecologia ; 192(1): 169-177, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31807865

RESUMO

Species diversity has been proposed to decrease prevalence of disease in a wide variety of host-pathogen systems, in a phenomenon labeled the dilution effect. This phenomenon was first proposed and tested for vector-borne diseases but was later extended to directly transmitted parasite systems such as hantavirus. Though there seems to be clear evidence for the dilution effect in some hantavirus/rodent systems, the generality of this hypothesis remains debated. In the present meta-analysis, we examined the evidence supporting the dilution effect for hantavirus/rodent systems in the Americas. General linear models employed on data from 56 field studies identified the abundance of the reservoir rodent species and its relative proportion in the community as the only relevant variables explaining the prevalence of antibodies against hantavirus in the reservoir. Thus, we found no clear support for the dilution effect hypothesis for hantavirus/rodent systems in the Americas.


Assuntos
Infecções por Hantavirus , Hantavirus , Américas , Animais , Biodiversidade , Roedores
6.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-LISBR1.1-46911

RESUMO

Lançado na última segunda-feira (18), novo relatório da Organização Pan-Americana da Saúde/Organização Mundial da Saúde (OPAS/OMS) destaca que um em cada cinco homens da região morre antes dos 50 anos – muitas dessas mortes estão diretamente relacionadas a uma “masculinidade tóxica”.


Assuntos
Masculinidade , Saúde do Homem , Américas/etnologia
7.
N Engl J Med ; 381(21): 2009-2019, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31693803

RESUMO

BACKGROUND: Dengue, a mosquito-borne viral disease, was designated a World Health Organization top 10 threat to global health in 2019. METHODS: We present primary efficacy data from part 1 of an ongoing phase 3 randomized trial of a tetravalent dengue vaccine candidate (TAK-003) in regions of Asia and Latin America in which the disease is endemic. Healthy children and adolescents 4 to 16 years of age were randomly assigned in a 2:1 ratio (stratified according to age category and region) to receive two doses of vaccine or placebo 3 months apart. Participants presenting with febrile illness were tested for virologically confirmed dengue by serotype-specific reverse-transcriptase polymerase chain reaction. The primary end point was overall vaccine efficacy in preventing virologically confirmed dengue caused by any dengue virus serotype. RESULTS: Of the 20,071 participants who were given at least one dose of vaccine or placebo (safety population), 19,021 (94.8%) received both injections and were included in the per-protocol analysis. The overall vaccine efficacy in the safety population was 80.9% (95% confidence interval [CI], 75.2 to 85.3; 78 cases per 13,380 [0.5 per 100 person-years] in the vaccine group vs. 199 cases per 6687 [2.5 per 100 person-years] in the placebo group). In the per-protocol analyses, vaccine efficacy was 80.2% (95% CI, 73.3 to 85.3; 61 cases of virologically confirmed dengue in the vaccine group vs. 149 cases in the placebo group), with 95.4% efficacy against dengue leading to hospitalization (95% CI, 88.4 to 98.2; 5 hospitalizations in the vaccine group vs. 53 hospitalizations in the placebo group). Planned exploratory analyses involving the 27.7% of the per-protocol population that was seronegative at baseline showed vaccine efficacy of 74.9% (95% CI, 57.0 to 85.4; 20 cases of virologically confirmed dengue in the vaccine group vs. 39 cases in the placebo group). Efficacy trends varied according to serotype. The incidence of serious adverse events was similar in the vaccine group and placebo group (3.1% and 3.8%, respectively). CONCLUSIONS: TAK-003 was efficacious against symptomatic dengue in countries in which the disease is endemic. (Funded by Takeda Vaccines; TIDES ClinicalTrials.gov number, NCT02747927.).


Assuntos
Vacinas contra Dengue/imunologia , Vírus da Dengue/imunologia , Dengue/prevenção & controle , Doenças Endêmicas/prevenção & controle , Adolescente , Américas/epidemiologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Ásia/epidemiologia , Criança , Pré-Escolar , Dengue/epidemiologia , Dengue/imunologia , Vacinas contra Dengue/efeitos adversos , Vírus da Dengue/isolamento & purificação , Método Duplo-Cego , Feminino , Humanos , Incidência , Masculino , Sorogrupo , Resultado do Tratamento
8.
Parasit Vectors ; 12(1): 463, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578140

RESUMO

Arboviruses infecting people primarily exist in urban transmission cycles involving urban mosquitoes in densely populated tropical regions. For dengue, chikungunya, Zika and yellow fever viruses, sylvatic (forest) transmission cycles also exist in some regions and involve non-human primates and forest-dwelling mosquitoes. Here we review the investigation methods and available data on sylvatic cycles involving non-human primates and dengue, chikungunya, Zika and yellow fever viruses in Africa, dengue viruses in Asia and yellow fever virus in the Americas. We also present current putative data that Mayaro, o'nyong'nyong, Oropouche, Spondweni and Lumbo viruses exist in sylvatic cycles.


Assuntos
Infecções por Arbovirus/veterinária , Arbovirus/isolamento & purificação , Doenças dos Primatas/virologia , África , Américas , Animais , Infecções por Arbovirus/virologia , Arbovirus/classificação , Ásia , Transmissão de Doença Infecciosa , Humanos
9.
Int J Infect Dis ; 88: 60-64, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499208

RESUMO

OBJECTIVES: The aim of this cross-sectional study was to describe the results of a systematic serological screening programme for strongyloidiasis. METHODS: A prospective serological screening programme for strongyloidiasis was performed between 2009 and 2014 for all immigrant patients attending the Tropical Medicine Unit. Three formalin-ether concentrated stool samples and an ELISA for anti-Strongyloides stercoralis antibodies were used as screening tools. RESULTS: Of 659 patients screened, 79 (12%) were positive for S. stercoralis regardless of the diagnostic method used. The prevalence of infection was 42.9% in East African patients, 16.3% in Central African patients, 10.9% in those from South America, and 10% in the case of West Africa. Univariate analysis showed that infection by S. stercoralis was significantly more frequent in patients from Central Africa (p=0.026; OR 1.72, 95% CI 1.03-2.85) and East Africa (p<0.001; OR 5.88, 95% CI 1.75-19.32). Taking West Africa as the reference (as the area of lowest prevalence among the positive prevalence areas), the statistical analysis showed that the risk of infection was higher in East Africa (p=0.001; OR 6.750, 95% CI 2.127-21.423) and Central Africa (p=0.065; OR 1.747, 95% CI 0.965-3.163). CONCLUSIONS: Due to the potential complications of strongyloidiasis infection, we recommend that immigrant patients from developing countries be routinely screened for S. stercoralis, especially those from East Africa. A serological test is a highly appropriate screening tool.


Assuntos
Emigrantes e Imigrantes/estatística & dados numéricos , Strongyloides/imunologia , Estrongiloidíase/diagnóstico , Adulto , África , Américas , Animais , Ásia , Estudos Transversais , Fezes/parasitologia , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Soroepidemiológicos , Espanha/epidemiologia , Strongyloides/isolamento & purificação , Estrongiloidíase/epidemiologia , Estrongiloidíase/parasitologia , Adulto Jovem
10.
Int J Infect Dis ; 88: 49-59, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499212

RESUMO

INTRODUCTION: While death due to Zika virus (ZIKV) infection has been described, reports of fatal cases have been infrequent and no systematic reviews on the subject have been published. METHODS: A systematic review of the literature in four databases was performed to assess fatal outcomes of postnatal ZIKV infection and the available evidence that links ZIKV infection to death. RESULTS: Three hundred and eleven articles were retrieved; 20 of them were epidemiological reports from surveillance agencies and ministries of health. After screening by abstract and title, 59 articles were selected for full-text assessment. Of these, 35 were excluded (with reasons) and 24 were finally included for qualitative analysis. A total of 51 reported deaths associated with ZIKV infection in nine countries were identified. The majority of cases (56.9%) were not related to Guillain-Barré syndrome. Cases from three countries accounted for 67.6% of the deaths. ZIKV infection was laboratory-confirmed in the majority of cases (64.7%). DISCUSSION: ZIKV was not considered to be a dangerous, and much less a lethal pathogen, until very recently. However, an increasing number of fatalities have been published in the literature since the first death was reported in 2016. Additional research is needed to elucidate factors that may mediate the pathogenesis of severe, atypical, and fatal disease.


Assuntos
Infecção por Zika virus/epidemiologia , Zika virus/fisiologia , Américas/epidemiologia , Humanos , Infecção por Zika virus/mortalidade , Infecção por Zika virus/virologia
11.
BMC Med ; 17(1): 171, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31474220

RESUMO

BACKGROUND: In 2015, the Zika virus spread from Brazil throughout the Americas, posing an unprecedented challenge to the public health community. During the epidemic, international public health officials lacked reliable predictions of the outbreak's expected geographic scale and prevalence of cases, and were therefore unable to plan and allocate surveillance resources in a timely and effective manner. METHODS: In this work, we present a dynamic neural network model to predict the geographic spread of outbreaks in real time. The modeling framework is flexible in three main dimensions (i) selection of the chosen risk indicator, i.e., case counts or incidence rate; (ii) risk classification scheme, which defines the high-risk group based on a relative or absolute threshold; and (iii) prediction forecast window (1 up to 12 weeks). The proposed model can be applied dynamically throughout the course of an outbreak to identify the regions expected to be at greatest risk in the future. RESULTS: The model is applied to the recent Zika epidemic in the Americas at a weekly temporal resolution and country spatial resolution, using epidemiological data, passenger air travel volumes, and vector habitat suitability, socioeconomic, and population data for all affected countries and territories in the Americas. The model performance is quantitatively evaluated based on the predictive accuracy of the model. We show that the model can accurately predict the geographic expansion of Zika in the Americas with the overall average accuracy remaining above 85% even for prediction windows of up to 12 weeks. CONCLUSIONS: Sensitivity analysis illustrated the model performance to be robust across a range of features. Critically, the model performed consistently well at various stages throughout the course of the outbreak, indicating its potential value at any time during an epidemic. The predictive capability was superior for shorter forecast windows and geographically isolated locations that are predominantly connected via air travel. The highly flexible nature of the proposed modeling framework enables policy makers to develop and plan vector control programs and case surveillance strategies which can be tailored to a range of objectives and resource constraints.


Assuntos
Epidemias , Infecção por Zika virus/epidemiologia , Américas/epidemiologia , Brasil , Humanos , Saúde Pública
12.
Rev Panam Salud Publica ; 43, September 2019
Artigo em Espanhol | PAHO-IRIS | ID: phr-51572

RESUMO

[ESPAÑOL]. Corrigendum a Distribución de la fuerza de trabajo en enfermería en la Región de las Américas. La Revista Panamericana de Salud Pública llama la atención a los lectores sobre un error en el siguiente artículo, señalado por los autores: Cassiani SHB, Hoyos MC, Barreto MFC, Sives K, da Silva FAM. Distribución de la fuerza de trabajo en enfermería en la Región de las Américas. Rev Panam Salud Publica. 2018;42:e72. https://doi.org/10.26633/RPSP.2018.72 . En la página 3, cuadro 1, el número de enfermeros por 10 000 habitantes en Argentina (2015) es 42,4 en lugar de 4,24.


[ENGLISH]. Corrigendum to Distribution of the nursing workforce in the Region of the Americas. The Pan American Journal of Public Health draws readers' attention to an error in the following article, pointed out by the authors: Cassiani SHB, Hoyos MC, Barreto MFC, Sives K, da Silva FAM. Distribución de la fuerza de trabajo en enfermería en la Región de las Américas. Rev Panam Salud Publica. 2018;42:e72. https://doi.org/10.26633/RPSP.2018.72. In page 3, table 1, the number of nurses per 10 000 inhabitants in Argentina (2015) is 42,4 instead of 4,24.


[PORTUGUÊS]. Corrigendum à Distribuição da força de trabalho de enfermagem na Região das Américas. A Revista Panamericana de Salud Pública chama a atenção dos leitores para um erro no artigo a seguir, apontado pelos autores: Cassiani SHB, Hoyos MC, Barreto MFC, Sives K, da Silva FAM. Distribución de la fuerza de trabajo en enfermería en la Región de las Américas. Rev Panam Salud Publica. 2018;42:e72. https://doi.org/10.26633/RPSP.2018.72. Na página 3, tabela 1, o número de enfermeiros por 10 000 habitantes na Argentina (2015) é de 42,4 em vez de 4,24.


Assuntos
Emprego , Recursos Humanos , Recursos Humanos de Enfermagem , Américas , Emprego , Recursos Humanos de Enfermagem , Américas , Emprego , Recursos Humanos de Enfermagem
13.
Washington, D.C.; PAHO; 2019-09-23.
em Inglês | PAHO-IRIS | ID: phr-51570

RESUMO

In the last decades, health in the Region of the Americas has improved dramatically, yet many people are being left behind. PAHO has established the Commission on Equity and Health Inequalities in the Americas to analyze the impact of drivers influencing health, while proposing actions to improve inequalities in health. According to the evidence presented in this report, much of ill health is socially determined. Factors such as socioeconomic position, ethnicity, gender, sexual orientation, disability status, being a migrant—alone or in combination—can contribute to marked inequalities in health on life. The analysis also reveals that other structural factors, such as climate change, environmental threats, and one’s relationship with the land, as well as the continuing impact of colonialism and racism, are also slowing progress towards a dignified life and enjoying the highest attainable standards of health. Furthermore, the impact of daily life conditions shows that the effect of inequalities is seen at the start of life. The report provides examples of successful policies, programs, and actions implemented in countries and presents 12 recommendations to achieve health equity, calling for coordinated actions among local and national governments, transnational organizations, and civil society to jointly address the social determinants of health.


Assuntos
Equidade em Saúde , Américas
14.
Washington, D.C.; OPS; 2019-09-23.
em Espanhol | PAHO-IRIS | ID: phr-51569

RESUMO

En los últimos decenios, la salud ha mejorado notablemente en la Región de las Américas. A pesar de ello, muchas personas se están quedando atrás. La OPS estableció la Comisión sobre Equidad y Desigualdades en Salud en las Américas para analizar el impacto de los determinantes que influyen en la salud y proponer medidas encaminadas a reducir las desigualdades en este ámbito. Según la evidencia presentada en este informe, la mala salud se debe en gran medida a los determinantes sociales. Ciertos factores —como la posición socioeconómica, el origen étnico, el género, la orientación sexual, la discapacidad y la condición de migrante— pueden contribuir, solos o combinados, a que haya marcadas desigualdades en la salud. El análisis también muestra que otros factores estructurales —como el cambio climático, las amenazas ambientales, la relación de las personas con la tierra y los efectos persistentes del colonialismo y el racismo— también están frenando el progreso hacia una vida digna y el goce del grado máximo de salud que se pueda lograr. Además, el impacto de las condiciones de la vida cotidiana muestra que el efecto de las desigualdades se observa al comienzo de la vida. En el informe se presentan ejemplos de políticas, programas y acciones eficaces de los países y se formulan doce recomendaciones para lograr la equidad en la salud mediante la acción coordinada de los gobiernos locales y nacionales, las organizaciones transnacionales y la sociedad civil, a fin de abordar conjuntamente los determinantes sociales de la salud.


Assuntos
Equidade em Saúde , Efeitos Contextuais das Desigualdades em Saúde , Américas
15.
Washington, D.C.; OPS; 2019-09-16. (OPS/HSS/19-03).
em Espanhol | PAHO-IRIS | ID: phr-51550

RESUMO

La finalidad de este documento es presentar ejemplos y principios clave para la utilización de las decisiones de autoridades regulatorias de otras jurisdicciones. Este documento se justifica por varias razones: a) da seguimiento a las deliberaciones de la conferencia del 2016 de la Red Panamericana para la Armonización de la Reglamentación Farmacéutica (Red PARF) y b) responde a la recomendación de dicha conferencia de que se solicite a la Organización Panamericana de la Salud (OPS) que elabore un documento conceptual para la consideración y el aval de los interesados de la Red PARF sobre el tema de la utilización de decisiones de autoridades regulatorias de otras jurisdicciones. El presente documento se basa en una ponencia presentada en la conferencia del 2016 e integra el pensamiento mundial sobre el tema, incluido un documento reciente de la Organización Mundial de la Salud. La meta fundamental es que los interesados de la Red comprendan mejor la utilización de las decisiones de autoridades regulatorias de otras jurisdicciones y las situaciones en que es factible.


Assuntos
Acesso a Medicamentos Essenciais e Tecnologias em Saúde , Controle de Medicamentos e Entorpecentes , Regulação e Fiscalização em Saúde , Américas , Barreiras ao Acesso aos Cuidados de Saúde , Acesso aos Serviços de Saúde , Legislação em Ciência e Tecnologia , Autoridades de Saúde , Colaboração Intersetorial
16.
Washington, D.C.; PAHO; 2019-09-16. (PAHO/HSS/19-003).
em Inglês | PAHO-IRIS | ID: phr-51549

RESUMO

The aim of this document is to outline key examples and principles for the practice of regulatory reliance. Its rationale is multifold: (a) it follows on previous discussions at the 2016 Conference of the Pan American Network for Drug Regulatory Harmonization (PANDRH), and (b) it fulfills a recommendation by the Conference that requested PAHO to develop a concept paper on reliance for PANDRH stakeholders to consider for endorsement. This concept paper builds on a presentation that was made at the 2016 Conference and integrates global thinking on the subject, including a recent document by the World Health Organization (WHO). The overarching goal is to ensure that PANDRH stakeholders continue to build understanding around reliance in ways that can better inform scenarios for its use.


Assuntos
Controle de Medicamentos e Entorpecentes , Acesso a Medicamentos Essenciais e Tecnologias em Saúde , Américas , Regulação e Fiscalização em Saúde , Barreiras ao Acesso aos Cuidados de Saúde , Acesso aos Serviços de Saúde , Legislação em Ciência e Tecnologia , Autoridades de Saúde , Colaboração Intersetorial
17.
Acta Trop ; 199: 105131, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31401192

RESUMO

Chikungunya is a viral disease caused by chikungunya virus (CHIKV) belonging to the Alphavirus genus and transmitted to humans by mosquitoes of Aedes spp. Nearly 40 countries in Asia, Africa, Europe, and the Americas have documented chikungunya cases. Most recent severe outbreaks have occurred in Indian Ocean islands of Réunion and Mauritius and India. There is no specific drug treatment for the disease, neither is there a standardized vaccine available for prevention of the disease. The present review gives a global perspective on patents filed pertaining to chikungunya. The United States has been the top patent filing jurisdiction followed by China, Europe, and India. The patents have been classified into categories of therapeutics, diagnostics, and vaccines. Maximum patent documents fall under the therapeutics category, in which patent applications are predominantly related to chemically derived drugs. They include nucleic acid analogues, various other host and virus enzyme/protein inhibitors. Patents on biological or plant derived drugs are being filed relatively recently. In the category of diagnostics, immunoassay based tests seemed to be of choice until the year 2005, whereas, patent filings for molecular diagnostics have now surpassed those with immunoassay techniques. In the vaccines category, vaccines based on viral vectors appear to be emerging as the preferred vaccine platform with the majority of patents filed in the years 2014-2017. Corporate sector has the most patent filings to its credit, followed closely by academic institutions. Pasteur Institut along with Chinese Agency for Science, Technology and Research is the top patent filing entity in chikungunya related technology space. Presently, nine vaccine products, three antiviral drugs and one mRNA based gene therapy are under development. Three vaccine products have been given fast track designation by US Food and Drug Administration (FDA) to expedite review and facilitate the development of a vaccine to prevent a serious or life-threatening condition and fill an unmet medical need. Similarly, one vaccine has been given PRIME (Priority Medicines) status by the European Medicines Agency (EMA).


Assuntos
Febre de Chikungunya/diagnóstico , Vírus Chikungunya/imunologia , Surtos de Doenças , Patentes como Assunto/estatística & dados numéricos , Vacinas Virais , Aedes/virologia , África/epidemiologia , Américas/epidemiologia , Animais , Ásia/epidemiologia , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/prevenção & controle , Vírus Chikungunya/genética , China , Surtos de Doenças/prevenção & controle , Europa (Continente)/epidemiologia , Humanos , Índia , Mosquitos Vetores/virologia , Ilhas do Pacífico/epidemiologia , Estados Unidos
18.
Infect Dis Clin North Am ; 33(3): 807-815, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395146

RESUMO

Ending the HIV Epidemic: A Plan for America" (EtHE), launched by the Department of Health and Human Services (DHHS), is predicated on actionable data systems to monitor progress toward ambitious goals and to guide human immunodeficiency virus (HIV) testing, prevention, and treatment services. Situated on a status-neutral continuum of HIV prevention and care, EtHE relies on coordination across DHHS agencies and utilization of data systems established for programmatic purposes. Improving efficiencies and timeliness of existing data systems and harnessing the potential of novel data systems, including those afforded by social media, require big data science approaches and investment in technological and human resources.


Assuntos
Big Data , Ciência de Dados/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Adesão à Medicação , Retenção nos Cuidados , Américas/epidemiologia , Gerenciamento Clínico , Humanos
19.
Rev Bras Parasitol Vet ; 28(3): 451-457, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390434

RESUMO

The msp4 gene of A. marginale is unicodon, stable and mostly homogeneous, being considered as a useful marker for phylogeographic characterization of this bacterium. The objective of this work was to analyze the phylogeography of A. marginale based on the msp4 gene in beef cattle from the Brazilian Pantanal, compared to those found in other regions worldwide. The blood samples investigated were collected from 400 animals (200 cows and 200 calves) reared in five extensive breeding farms in this region. The results indicated that of the evaluated samples, 56.75% (227/400) were positive for A. marginale based on the msp1ß gene by quantitatitve PCR (qPCR), while 8.37% (19/227) were positive for the msp4 gene in the conventional PCR. In the Network distance analysis, 14 sequences from the Brazilian Pantanal were grouped into a single group with those from Thailand, India, Spain, Colombia, Parana (Brazil), Mexico, Portugal, Argentina, China, Venezuela, Australia, Italy and Minas Gerais (Brazil). Among 68 sequences from Brazil and the world, 15 genotypes were present while genotype number one (#1) was the most distributed worldwide. Both Splitstree and network analyses showed that the A. marginale msp4 sequences detected in beef cattle from the Brazilian Pantanal showed low polymorphism, with the formation of one genogroup phylogenetically related to those found in ruminants from South and Central America, Europe, and Asia.


Assuntos
Anaplasma marginale/genética , Proteínas de Bactérias/genética , Bovinos/microbiologia , Proteínas de Membrana/genética , Filogeografia/métodos , Américas , Sequência de Aminoácidos , Anaplasma marginale/isolamento & purificação , Animais , Ásia , Brasil , DNA Bacteriano/genética , Europa (Continente) , Feminino , Genótipo , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
20.
Rev Panam Salud Publica ; 43, August 2019
Artigo em Inglês | PAHO-IRIS | ID: phr-51511

RESUMO

To the editor: Dengue, zika, and chikungunya outbreaks in Central and South America countries have presented significant challenges related to their prevention and control. From the virologic point of view, the possibility has been raised that the co-circulation of the three viruses could generate cross-protection between the three alphaviruses. In order to discuss this hypothesis it must be taken into account that Zika, dengue (DENV) and chikungunya viruses are closely related flaviviruses, with identical urban transmission and some immune interactions (1). Also, it is known that secondary DENV infections may be more severe than primary infections due to the antibody-dependent immune response (i.e., heterotypic sub-neutralizing antibodies that increase virus entry into poorly susceptible cells) (2,3). In addition, the recent introduction of Zika and chikungunya viruses in the Americas and the large-scale exposure of a uniformly unexposed population could affect subsequent transmission of dengue virus. This hypothesis has not been tested, largely because insufficient epidemiological data are available for the affected sites. However, in Salvador, Brazil, after the zika outbreak there was a significant decrease in the frequency of dengue cases (4). A similar situation was observed in Colombia, where the decrease in dengue cases following the zika and chikungunya outbreaks went from 334.1 cases per 100 000 people in 2015 to 90.7 cases per 100 000 in 2017 and 173,1 cases per 100 000 in 2018 (5). Although temporary associations do not prove causation, the strength and consistency of the observations suggest that infections with Zika virus and chikungunya virus could induce cross-protective immunity against dengue. Prospective studies are needed to fully assess the risk of dengue infection after exposure to Zika and chikungunya viruses and to determine whether the supposed cross-protection is long-lasting. Although observations support this hypothesis, the potential direct implications of this hypothesis for epidemiological surveillance, immunological research on pathogenesis and vaccine development require additional studies.


Assuntos
Zika virus , Dengue , Vírus Chikungunya , Américas , Vírus , Colômbia
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