7,587 results match your criteria Yellow Fever

Relationship between vertical stratification and feeding habits of mosquito (Diptera: Culicidae) assemblages collected in conservation units in the green belt of the city of São Paulo, Brazil.

Acta Trop 2021 Jun 11:106009. Epub 2021 Jun 11.

Department of Epidemiology, School of Public Health, University of São Paulo, São Paulo, SP, Brazil. Electronic address:

São Paulo is one of the largest cities in the world and has several characteristics that favor a diversity of urban and wild mosquitoes. Little is known about how variations in mosquito diversity and feeding preferences for different hosts in different vegetation strata can influence the risk of pathogen transmission to humans. We investigated vertical stratification of mosquitoes and its relationship with vertebrate hosts in environments with different degrees of conservation in two conservation units in the city of São Paulo. Read More

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Testing the genomic stability of the Brazilian yellow fever vaccine strain using next-generation sequencing data.

Interface Focus 2021 Jun 11;11(4):20200063. Epub 2021 Jun 11.

National Laboratory for Scientific Computing, Bioinformatics Laboratory (LABINFO), Avenida Getúlio Vargas, 333, Quitandinha 25651-075, Petrópolis, Rio de Janeiro, Brazil.

The live attenuated yellow fever (YF) vaccine was developed in the 1930s. Currently, the 17D and 17DD attenuated substrains are used for vaccine production. The 17D strain is used for vaccine production by several countries, while the 17DD strain is used exclusively in Brazil. Read More

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Larvicidal potential of cell wall degrading enzymes from Trichoderma asperellum against Aedes aegypti (Diptera: Culicidae).

Biotechnol Prog 2021 Jun 11. Epub 2021 Jun 11.

Laboratório de Química de Polímeros (LQP) - ICB2 - Universidade Federal de Goiás, Goiânia, GO, Brazil.

Background: Aedes aegypti is a mosquito vector of arboviruses such as Dengue, Chikungunya, Zika and Yellow Fever that cause important public health diseases. The incidence and gravity of these diseases justifies the search for effective measures to reduce the presence of this vector in the environment. Bioinsecticides are an effective alternative method for insect control, with added ecological benefits such as biodegradability. Read More

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[Recrudescence of yellow fever in Chad: case report of the last confirmed case in the health district of Lai-Chad].

Pan Afr Med J 2021 8;38:248. Epub 2021 Mar 8.

CHU de la Référence, N´Djamena, Tchad.

Yellow fever (YF) is a viral haemorrhagic fever caused by yellow fever virus transmitted by Aedes mosquitoes. Since 2013, in Chad, four cases of yellow fever have been detected and confirmed as part of the national fever surveillance program. We here report the last clinical case confirmed in the health district of Lai. Read More

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The impact of viral infections on childhood central nervous system infections.

J Clin Virol 2021 Jul 11;140:104853. Epub 2021 May 11.

Laboratório de Vírus, Departamento de Microbiologia, Universidade Federal de Minas Gerais, Minas Gerais, Brazil. Electronic address:

Background: Viruses are a common cause of central nervous system (CNS) infections. However, studies of CNS viral pathogens in pediatric patients are poorly explored because viral infections are often erroneously diagnosed as bacterial infections.

Methods: 299 CNS samples were collected from pediatric patients aged from one month to 14 years old. Read More

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Technical viability of the YF MAC-HD ELISA kit for use in yellow fever-endemic regions.

PLoS Negl Trop Dis 2021 Jun 4;15(6):e0009417. Epub 2021 Jun 4.

Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America.

Yellow fever (YF), an arboviral disease, affects an estimated 200,000 people and causes 30,000 deaths per year and recently has caused major epidemics in Africa and South America. Timely and accurate diagnosis of YF is critical for managing outbreaks and implementing vaccination campaigns. A YF immunoglobulin M (IgM) antibody-capture (MAC) enzyme-linked immunosorbent assay (ELISA) kit, the YF MAC-HD, was successfully introduced starting in 2018 to laboratories in Africa and South America. Read More

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Arthropods as potential vectors of African swine fever virus outbreaks in pig farms in the Republic of Korea.

Vet Med Sci 2021 Jun 4. Epub 2021 Jun 4.

Department of Animal Disease Control and Quarantine, Animal and Plant Quarantine Agency, Gimcheon, Republic of Korea.

The seasonality of African swine fever (ASF) in the summers and outbreaks in farms with high biosecurity levels suggest that the ASF virus (ASFV) may be transmitted by arthropod vectors. Arthropods were collected in this study from 14 pig farms with ASF outbreaks in Korea in 2019 to explore the role of arthropods as potential ASFV vectors. A total of 28,729 arthropods, including 28,508 (99. Read More

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Safety and immunogenicity of Vi-typhoid conjugate vaccine co-administration with routine 9-month vaccination in Burkina Faso: A randomised controlled phase 2 trial.

Int J Infect Dis 2021 May 31. Epub 2021 May 31.

Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA. Electronic address:

Objectives: In 2017, the World Health Organisation (WHO) pre-qualified a single-dose typhoid conjugate vaccine (TCV) and identified TCV co-administration studies as a research priority. We tested co-administration of Typbar TCV® (Bharat Biotech International) with measles-rubella (MR) and yellow fever (YF) vaccines.

Methods: We conducted a randomised, double-blind, and controlled, phase 2 trial in Ouagadougou, Burkina Faso. Read More

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The epidemiology of Mayaro virus in the Americas: A systematic review and key parameter estimates for outbreak modelling.

PLoS Negl Trop Dis 2021 Jun 3;15(6):e0009418. Epub 2021 Jun 3.

MRC Centre for Global Infectious Disease Analysis (MRC-GIDA), Imperial College London, London, United Kingdom.

Mayaro virus (MAYV) is an arbovirus that is endemic to tropical forests in Central and South America, particularly within the Amazon basin. In recent years, concern has increased regarding MAYV's ability to invade urban areas and cause epidemics across the region. We conducted a systematic literature review to characterise the evolutionary history of MAYV, its transmission potential, and exposure patterns to the virus. Read More

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Prior heterologous flavivirus exposure results in reduced pathogenesis in a mouse model of Zika virus infection.

J Virol 2021 Jun 2:JVI0057321. Epub 2021 Jun 2.

Department of Molecular Microbiology and Immunology, Saint Louis University- School of Medicine, Saint Louis, Missouri, USA.

The 2015/16 Zika virus epidemic in South and Central America left the scientific community urgently trying to understand the factors that contribute to Zika virus pathogenesis. Because multiple other flaviviruses are endemic in areas where Zika virus emerged, it is hypothesized that a key to understanding Zika virus disease severity, is to study Zika virus infection in the context of prior flavivirus exposure. Human and animal studies have highlighted the idea that having been previously exposed to a different flavivirus may modulate the immune response to Zika virus. Read More

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Vaccine fake news: an analysis under the World Health Organization's 3Cs model.

Rev Esc Enferm USP 2021 26;55:e03736. Epub 2021 May 26.

Universidade Federal de Minas Gerais, Escola de Enfermagem, Departamento de Enfermagem Materno Infantil e Saúde Pública, Belo Horizonte, MG, Brasil.

Objective: To analyze fake news about immunobiologicals using as reference vaccine hesitancy in the World Health Organization's 3Cs model (confidence, complacency and convenience).

Method: This is an exploratory qualitative research that used content analysis to analyze fake news on three national news-checking sites.

Results: Twenty fake news related to immunobiologicals were analyzed, with 55% published in 2018 and 63% related to yellow fever vaccine. Read More

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Mosquito-Associated Viruses and Their Related Mosquitoes in West Africa.

Viruses 2021 May 12;13(5). Epub 2021 May 12.

Bernhard Nocht Institute for Tropical Medicine, WHO Collaborating Centre for Arbovirus and Hemorrhagic Fever Reference and Research, 20359 Hamburg, Germany.

Mosquito-associated viruses (MAVs), including mosquito-specific viruses (MSVs) and mosquito-borne (arbo)viruses (MBVs), are an increasing public, veterinary, and global health concern, and West Africa is projected to be the next front for arboviral diseases. As in-depth knowledge of the ecologies of both western African MAVs and related mosquitoes is still limited, we review available and comprehensive data on their diversity, abundance, and distribution. Data on MAVs' occurrence and related mosquitoes were extracted from peer-reviewed publications. Read More

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Molecular Insights into the Flavivirus Replication Complex.

Viruses 2021 May 21;13(6). Epub 2021 May 21.

Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore.

Flaviviruses are vector-borne RNA viruses, many of which are clinically relevant human viral pathogens, such as dengue, Zika, Japanese encephalitis, West Nile and yellow fever viruses. Millions of people are infected with these viruses around the world each year. Vaccines are only available for some members of this large virus family, and there are no effective antiviral drugs to treat flavivirus infections. Read More

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Species composition and risk of transmission of some Aedes-borne arboviruses in some sites in Northern Ghana.

PLoS One 2021 1;16(6):e0234675. Epub 2021 Jun 1.

Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana.

Aedes-borne viral diseases mainly Yellow Fever (YF), Dengue (DEN), Zika (ZIK) and Chikungunya (CHK) have contributed to many deaths' in the world especially in Africa. There have been major outbreaks of these diseases in West Africa. Although, YF outbreaks have occurred in Ghana over the years, no outbreak of DEN, ZIK and CHK has been recorded. Read More

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Mechanisms Underlying Host Range Variation in Flavivirus: From Empirical Knowledge to Predictive Models.

J Mol Evol 2021 Jul 31;89(6):329-340. Epub 2021 May 31.

School of Plant Sciences and Food Security, George S. Wise Faculty of Life Sciences, Tel Aviv University, 69978, Tel Aviv-Yafo, Israel.

Preventing and controlling epidemics caused by vector-borne viruses are particularly challenging due to their diverse pool of hosts and highly adaptive nature. Many vector-borne viruses belong to the Flavivirus genus, whose members vary greatly in host range and specificity. Members of the Flavivirus genus can be categorized to four main groups: insect-specific viruses that are maintained solely in arthropod populations, mosquito-borne viruses and tick-borne viruses that are transmitted to vertebrate hosts by mosquitoes or ticks via blood feeding, and those with no-known vector. Read More

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Repurposing Infectious Diseases Vaccines Against Cancer.

Front Oncol 2021 13;11:688755. Epub 2021 May 13.

The Anticancer Fund, Strombeek-Bever, Belgium.

Vaccines used to prevent infections have long been known to stimulate immune responses to cancer as illustrated by the approval of the Bacillus Calmette-Guérin (BCG) vaccine to treat bladder cancer since the 1970s. The recent approval of immunotherapies has rejuvenated this research area with reports of anti-tumor responses with existing infectious diseases vaccines used as such, either alone or in combination with immune checkpoint inhibitors. Here, we have reviewed and summarized research activities using approved vaccines to treat cancer. Read More

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Comparative Skip-Oviposition Behavior Among Container Breeding Aedes spp. Mosquitoes (Diptera: Culicidae).

J Med Entomol 2021 May 28. Epub 2021 May 28.

Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA.

Container Aedes mosquitoes are the most important vectors of human arboviruses (i.e., dengue, chikungunya, Zika, or yellow fever). Read More

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A second generation of 1,2,4-oxadiazole derivatives with enhanced solubility for inhibition of 3-hydroxykynurenine transaminase (HKT) from .

RSC Med Chem 2021 Mar 9;12(2):222-236. Epub 2020 Dec 9.

Department of Fundamental Chemistry, Federal University of Pernambuco (UFPE) Recife - PE Brazil

The most widely used method for the control of the mosquito population is the chemical control method. It represents a time- and cost-effective way to curb several diseases ( dengue, Zika, chikungunya, yellow fever) through vector control. For this reason, the discovery of new compounds with a distinct mode of action from the available ones is essential in order to minimize the rise of insecticide resistance. Read More

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Intradermal Vaccination: A Potential Tool in the Battle Against the COVID-19 Pandemic?

Risk Manag Healthc Policy 2021 20;14:2079-2087. Epub 2021 May 20.

Primary Care Unit ASL RM 1, Rome, Italy.

This narrative review is the final output of an initiative of the SIM (Italian Society of Mesotherapy). A narrative review of scientific literature on the efficacy of fractional intradermal vaccination in comparison with full doses has been conducted for the following pathogens: influenza virus, rabies virus, poliovirus (PV), hepatitis B virus (HBV), hepatitis A virus (HAV), diphtheria-tetanus-pertussis bacterias (DTP), human papillomavirus (HPV), Japanese encephalitis virus (JE), meningococcus, varicella zoster virus (VZV) and yellow fever virus. The findings suggest that the use of the intradermal route represents a valid strategy in terms of efficacy and efficiency for influenza, rabies and HBV vaccines. Read More

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First report of epidemic dengue fever among Internally Displaced Persons in humanitarian camps of North Darfur, Sudan.

Int J Infect Dis 2021 May 24. Epub 2021 May 24.

World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, Texas, USA; Institute for Human Infections and Immunity and Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA. Electronic address:

Objectives: The aim of this study was to investigate an outbreak of a non-malaria undifferentiated febrile illness among internally displaced persons (IDPs) living in humanitarian camps in North Darfur, Sudan in 2019.

Methods: An investigation team was deployed to the State to identify and collect blood samples, clinical and demographical data from the suspected-cases. Blood samples were examined forPlasmodium falciparum using microscope and tested for dengue (DENV) and Yellow fever viruses using commercial RT-qPCR kits. Read More

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Divergent clonal differentiation trajectories establish CD8 memory T cell heterogeneity during acute viral infections in humans.

Cell Rep 2021 May;35(8):109174

Department of Cell and Molecular Biology, Karolinska Institutet, 171 77 Stockholm, Sweden. Electronic address:

The CD8 T cell response to an antigen is composed of many T cell clones with unique T cell receptors, together forming a heterogeneous repertoire of effector and memory cells. How individual T cell clones contribute to this heterogeneity throughout immune responses remains largely unknown. In this study, we longitudinally track human CD8 T cell clones expanding in response to yellow fever virus (YFV) vaccination at the single-cell level. Read More

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Dengvaxia: the world's first vaccine for prevention of secondary dengue.

Ther Adv Vaccines Immunother 2021 17;9:25151355211015839. Epub 2021 May 17.

Wingate University School of Pharmacy, Levine College of Health Sciences, 515 North Main Street, Wingate, NC 28174, USA.

The objective of this manuscript was to review and evaluate the efficacy and safety data of Dengvaxia for the treatment of severe secondary dengue infection. Dengvaxia is the brand name for chimeric yellow fever-dengue-tetravalent dengue vaccine (CYD-TDV). A literature search through PubMed was conducted using the keywords 'dengue vaccine', 'Dengvaxia', 'efficacy' or 'safety'. Read More

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Vector saliva controlled inflammatory response of the host may represent the Achilles heel during pathogen transmission.

J Venom Anim Toxins Incl Trop Dis 2021 May 17;27:e20200155. Epub 2021 May 17.

Institut Pasteur, Unité de Biologie des Interactions Hôte Parasites, Paris, France.

Infection with vector-borne pathogens starts with the inoculation of these pathogens during blood feeding. In endemic regions, the population is regularly bitten by naive vectors, implicating a permanent stimulation of the immune system by the vector saliva itself (pre-immune context). Comparatively, the number of bites received by exposed individuals from non-infected vectors is much higher than the bites from infected ones. Read More

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miRNAs of Aedes aegypti (Linnaeus 1762) conserved in six orders of the class Insecta.

Sci Rep 2021 May 21;11(1):10706. Epub 2021 May 21.

Universidad Autonoma de Nuevo Leon, Facultad de Ciencias Biologicas, Departamento de Zoologia de Invertebrados, Laboratorio de Entomologia Medica , Av. Universidad S/N CD. Universitaria, 66455, San Nicolas de los Garza, Nuevo Leon, Mexico.

Aedes aegypti L. is the most important vector of arboviruses such as dengue, Zika, chikungunya, Mayaro, and yellow fever, which impact millions of people's health per year. MicroRNA profile has been described in some mosquito species as being important for biological processes such as digestion of blood, oviposition, sexual differentiation, insecticide resistance, and pathogens dissemination. Read More

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Multimodal integration across spatiotemporal scales to guide invertebrate locomotion.

Integr Comp Biol 2021 May 1. Epub 2021 May 1.

Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.

Locomotion is a hallmark of organisms that has enabled adaptive radiation to an extraordinarily diverse class of ecological niches, and allows animals to move across vast distances. Sampling from multiple sensory modalities enables animals to acquire rich information to guide locomotion. Locomotion without sensory feedback is haphazard, therefore sensory and motor systems have evolved complex interactions to generate adaptive behavior. Read More

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Steroidal saponins from the roots of Solanum sisymbriifolium Lam. (Solanaceae) have inhibitory activity against dengue virus and yellow fever virus.

Braz J Med Biol Res 2021 17;54(7):e10240. Epub 2021 May 17.

Laboratório de Virologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil.

Dengue is the most important arthropod-borne viral disease worldwide. Infection with any of the four dengue virus (DENV) serotypes can be asymptomatic or lead to disease with clinical symptoms ranging from undifferentiated and self-limiting fever to severe dengue disease, which can be fatal in some cases. Currently, no specific antiviral compound is available for treating DENV. Read More

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Vaccination reshapes the virus-specific T cell repertoire in unexposed adults.

Immunity 2021 Jun 18;54(6):1245-1256.e5. Epub 2021 May 18.

Department of Medicine, Division of Rheumatology, Perelman School of Medicine, Institute for Immunology, University of Pennsylvania, Philadelphia, PA 19104, USA; Corporal Michael J Crescenz VA Medical Center, Philadelphia, PA 19104, USA. Electronic address:

We examined how baseline CD4 T cell repertoire and precursor states impact responses to pathogen infection in humans using primary immunization with yellow fever virus (YFV) vaccine. YFV-specific T cells in unexposed individuals were identified by peptide-MHC tetramer staining and tracked pre- and post-vaccination by tetramers and TCR sequencing. A substantial number of YFV-reactive T cells expressed memory phenotype markers and contained expanded clones in the absence of exposure to YFV. Read More

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Serum biomarker profile orchestrating the seroconversion status of patients with autoimmune diseases upon planned primary 17DD Yellow fever vaccination.

Sci Rep 2021 May 17;11(1):10431. Epub 2021 May 17.

Grupo Integrado de Pesquisas Em Biomarcadores, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ-Minas), Avenida Augusto de Lima 1715, Barro Preto, Belo Horizonte, MG, 30190-002, Brazil.

The present study aimed to investigate whether the serum biomarkers of immune response orchestrate the seroconversion status in patients with autoimmune diseases (AID) upon planned primary 17DD-YF vaccination. For this purpose a total of 161 individuals were enrolled in a prospective study, including patients with Rheumatoid Arthritis (RA = 38), Spondyloarthritis (SpA = 51), Systemic Lupus Erythematosus (SLE = 21) and Sjögren's Syndrome (SS = 30) along with a group of healthy controls (HC = 21). Analysis of plaque reduction neutralization test (PRNT) titers and seropositivity rates along with the 17DD-YF viremia and serum biomarkers were carried out at distinct time points (D0/D3-4/D5-6/D7/D14-28). Read More

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