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Yellow Fever prevention strategies awareness among HIV-infected patients in São Paulo, Brazil.

INTRODUCTION: Vaccination is the main preventive strategy against Yellow Fever (YF), which is a public health concern in Brazil. However, HIV-infected patients might have insufficient knowledge regarding YF, YF prevention, and vaccines in general. METHODS: In this questionnaire-based study, data from 158 HIV-infected individuals were addressed in three distinct outpatient clinics in São Paulo. Information was collected on demographic and clinical characteristics, as well as patients' knowledge of vaccines, YF and YF preventive strategies. In addition, individual YF vaccine recommendations and…

Yellow fever epizootics in non-human primates, São Paulo state, Brazil, 2008-2009.

Since 2000, the expansion of Sylvatic Yellow Fever (YF) has been observed in the southeast of Brazil, being detected in areas considered silent for decades. Epizootics in non-human primates (NHPs) are considered sentinel events for the detection of human cases. It is important to report epizootic events that could have impact on the conservation status of susceptible species. We describe the epizootics in NHPs, notified in state of São Paulo, Brazil, between September 2008 to August 2009. Ninety-one epizootic events, involving 147 animals, were reported in 36 counties. Samples were obtained fr…

ATon, abundant novel nonautonomous mobile genetic elements in yellow fever mosquito (Aedes aegypti).

BACKGROUND: Mosquitoes are important pathogen vectors affecting human and other animals. Studies on genetic control of mosquito mediated dis … uito genomes are highly desirable. RESULTS: Starting with the transposable element database of the yellow fever mosquito Aedes aegypti genome, detailed analyses of the members of each TE family were performed to identify sequences with multiple identical copies, an indicator of their latest or current transposition activity. Among a dozen of potentially activ …

Entomological profile of yellow fever epidemics in the Central African Republic, 2006-2010.

BACKGROUND: The causative agent of yellow fever is an arbovirus of the Flaviviridae family transmitted by infected Aedes mosquitoes, particularly in Africa. In the Central African Republic since 2006, cases have been notified in the provinces of Ombella-Mpoko, Ouham-Pende, Basse-Kotto, Haute-Kotto and in Bangui the capital. As the presence of a vector of yellow fever virus (YFV) represents a risk for spread of the disease, we undertook entomological investigations at these sites to identify potential vectors of YFV and their abundance. FINDINGS: Between 2006 and 2010, 5066 mosquitoes belongin…

Docking studies towards exploring antiviral compounds against envelope protein of yellow fever virus.

Yellow fever is among one of the most lethal viral diseases for which approved antiviral therapies were yet to be discovered. Herein, functional assignment of complete YFV proteome was done through support vector machine. Major envelope (E) protein that mediates entry of YFV into host cell was selected as a potent molecular target. Three dimensional structure of the molecular target was predicted using Modeller9v7. The model was optimized in Maestro9.0 applying OPLS AA force field and was evaluated using PROCHECK, ProSA, ProQ and Profile 3D. The BOG pocket residues Val48, Glu197, Thr200, Ile20…

Genetic stability of a dengue vaccine based on chimeric yellow fever/dengue viruses.

A tetravalent dengue vaccine based on four live, attenuated, chimeric viruses (CYD1-4), constructed by replacing the genes coding for premembrane (prM) and envelope (E) proteins of the yellow fever (YF)-17D vaccine strain with those of the four serotypes of dengue virus, is in clinical phase III evaluation. We assessed the vaccine's genetic stability by fully sequencing each vaccine virus throughout the development and manufacturing process. The four viruses displayed complete genetic stability, with no change from premaster seed lots to bulk lots. When pursuing the virus growth beyond bulk lo…

Stability of yellow fever virus under recombinatory pressure as compared with chikungunya virus.

Recombination is a mechanism whereby positive sense single stranded RNA viruses exchange segments of genetic information. Recent phylogenetic analyses of naturally occurring recombinant flaviviruses have raised concerns regarding the potential for the emergence of virulent recombinants either post-vaccination or following co-infection with two distinct wild-type viruses. To characterize the conditions and sequences that favor RNA arthropod-borne virus recombination we constructed yellow fever virus (YFV) 17D recombinant crosses containing complementary deletions in the envelope protein coding …

Efficient, trans-complementing packaging systems for chimeric, pseudoinfectious dengue 2/yellow fever viruses.

In our previous studies, we have stated to build a new strategy for developing defective, pseudoinfectious flaviviruses (PIVs) and applying them as a new type of vaccine candidates. PIVs combined the efficiency of live vaccines with the safety of inactivated or subunit vaccines. The results of the present work demonstrate further development of chimeric PIVs encoding dengue virus 2 (DEN2V) glycoproteins and yellow fever virus (YFV)-derived replicative machinery as potential vaccine candidates. The newly designed PIVs have synergistically functioning mutations in the prM and NS2A proteins, whic…

[Vaccination against yellow fever among patients on immunosuppressors with diagnoses of rheumatic diseases].

Yellow fever is endemic in some countries. The anti-yellow fever vaccine is the only effective means of protection but is contraindicated for immunocompromised patients. The aim of this paper was to report on a case series of rheumatological patients who were using immunosuppressors and were vaccinated against this disease. This was a retrospective study by means of a questionnaire applied to these patients, who were vaccinated 60 days before the investigation. Seventy patients of mean age 46 years were evaluated. Most of them were female (90%). There were cases of rheumatoid arthritis (54), s…

Microsatellite isolation and linkage group identification in the yellow fever mosquito Aedes aegypti.

Microsatellites have proved to be very useful as genetic markers, as they seem to be ubiquitous and randomly distributed throughout most eukaryote genomes. However, our laboratories and others have determined that this paradigm does not necessarily apply to the yellow fever mosquito Aedes aegypti. We report the isolation and identification of microsatellite sequences from multiple genomic libraries for A. aegypti. We identified 6 single-copy simple microsatellites from 3 plasmid libraries enriched for (GA)(n), (AAT)(n), and (TAGA)(n) motifs from A. aegypti. In addition, we identified 5 single-…

Multiple evanescent white dot syndrome following simultaneous hepatitis-A and yellow fever vaccination.

PURPOSE: To report a case of multiple evanescent white dot syndrome (MEWDS) following simultaneous hepatitis-A virus (HAV) and yellow fever (YF) vaccination. METHODS: Review of the clinical, laboratory, photographic, and angiographic records of a patient suffering from MEWDS. RESULTS: A healthy 50-year-old woman presented with rapidly progressive left-eye visual loss, associated with photopsias and a para-central scotoma, one week after receiving simultaneous HAV and YF vaccination. Both anterior segments and right-eye fundus were unremarkable. Fundus examination of the left-eye disclosed pa…

Immunogenicity of WHO-17D and Brazilian 17DD yellow fever vaccines: a randomized trial.

OBJECTIVE: To compare the immunogenicity of three yellow fever vaccines from WHO-17D and Brazilian 17DD substrains (different seed-lots). METHODS: An equivalence trial was carried out involving 1,087 adults in Rio de Janeiro. Vaccines produced by Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brazil) were administered following standardized procedures adapted to allow blocked randomized allocation of participants to coded vaccine types (double-blind). Neutralizing yellow fever antibody titters were compared in pre- and post-immunization serum samples. Equivalence was defined as a difference of no m…

Подъемные элементы редукции Ribunocleotide из желтой лихорадки комаров, Aedes aegypti: клонирование и выражение.

Редуктаза Рибонуклеотида стимулирует деново синтез деоксирибонуклеотидов. Редукции первого класса используют железный центр для создания тиросилового свободного радикала, который может инициировать образование дезоксирибонуклеотида. Эти редукции представляют собой альфа-2 бета-2 голоэнзимы, а субъекты обозначаются как R1 и R2. R1 содержит аллостерический связной участок и активный объект, в то время как R2 содержит биядерный железный центр, который инициирует образование тиросил радикал. Мы клонировали и секвенировали CDNA, кодируя субъект R1 и R2 в желтой лихорадке комаров, Aedes aegypti. Свя

Совпадение в аннотации оригинала
Ribonucleotide reductase catalyses the de novo synthesis of deoxyribonucleotides. Class I reductases use an iron center to generate a tyrosy … f the tyrosyl radical. We have cloned and sequenced the cDNAs encoding the R1 and R2 subunit in the yellow fever mosquito, Aedes aegypti. The messages for these proteins are increased in response to blood-feeding.

Adverse events associated with 17D-derived yellow fever vaccination--United States, 2001-2002.

In June 2001, seven cases of yellow fever vaccine-associated viscerotropic disease (YEL-AVD) (previously called multiple organ system failure) in recipients of 17D-derived yellow fever vaccine (YEL) were reported to the Advisory Committee on Immunization Practices (ACIP). ACIP reviewed the cases, recommended enhanced surveillance for adverse events, and updated the ACIP statement on YEL. This report summarizes the preliminary surveillance findings, including two new suspected cases of YEL-AVD and four suspected cases of YEL-associated neurotropic disease (YEL-AND) (previously called postvaccin…

Experimental yellow fever virus infection in the Golden hamster (Mesocricetus auratus). II. Pathology.

Subadult and adult hamsters were inoculated intraperitoneally with 10(6) TCID(50) of yellow fever (YF) virus (Jimenez strain). Four animals from each group were subjected daily to histologic examination for 9 days. The liver showed spotty necrosis on day 3 after infection, which was followed by steatosis and focally confluent necrosis. In surviving hamsters, hepatocyte regeneration began on day 8, which was accompanied by decreasing steatosis. The spleen initially exhibited lymphoid hyperplasia, which was followed by lymphoid depletion and increased phagocytosis by splenic macrophages. Focal p…

Construction, characterization and immunogenicity of recombinant yellow fever 17D-dengue type 2 viruses.

Chimeric yellow fever (YF)-dengue type 2 (Den 2) viruses were constructed by replacing the premembrane (prM) and envelope (E) genes of YF 17D virus with those from Den 2 virus strains of south-east Asian genotype. Whereas viable chimeric viruses were successfully recovered when the YF 17D C gene and the Den 2 prM gene were fused at the signalase cleavage site, no virus could be rescued from the constructions fused at the viral protease cleavage site. Unlike YF virus that replicated in all the cell lines tested and similar to the Den 2 virus, the recombinant viruses did not replicate in vaccine…

[Sanitary battles and scientific clashes: Emilio Ribas and yellow fever in Sao Paulo].

Emilio Ribas, an administrative physician and sanitarian from Sao Paulo, was an advocate of the microbiological conception during the long period when he directed the Servico Sanitario de Sao Paulo (1898-1917). This article offers a brief analysis of his stance in the flight against yellow fever during the early 20th century, considered a highlight of his career. The scientists and professionals linked to this sanitary agency in Sao Paulo found themselves in a tense, unstable work environment, where experimental proof played an important role in corroborating new medical-sanitary conceptions a…

Yellow fever 17D vaccine virus isolated from healthy vaccinees accumulates very few mutations.

The live attenuated yellow fever (YF) vaccine strain 17D is one of the safest vaccines in use today with only 22 cases of reversion to virulence documented from over 300 million doses administered. We have isolated virus in cell culture from sera of six volunteers who received 17D vaccine and found that very few nucleotide mutations were detected in the consensus sequence of the entire genome of each of the serum viruses. Moreover, most of these mutations accumulated in the non-structural protein genes, especially the NS5 protein gene. Although no nucleotide change was identified in the struct…

First recorded outbreak of yellow fever in Kenya, 1992-1993. I. Epidemiologic investigations.

Outbreaks of yellow fever (YF) have never been recorded in Kenya. However, in September 1992, cases of hemorrhagic fever (HF) were reported in the Kerio Valley to the Kenya Ministry of Health. Early in 1993, the disease was confirmed as YF and a mass vaccination campaign was initiated. Cases of suspected YF were identified through medical record review and hospital-based disease surveillance by using a clinical case definition. Case-patients were confirmed serologically and virologically. We documented 55 persons with HF from three districts of the Rift Valley Province in the period of Septemb…