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Persistence of yellow fever vaccine-induced antibodies after solid organ transplantation.

Immunization using live attenuated vaccines represents a contra-indication after solid organ transplantation (SOT): consequently, transplant candidates planning to travel in countries where yellow fever is endemic should be vaccinated prior to transplantation. The persistence of yellow fever vaccine-induced antibodies after transplantation has not been studied yet. We measured yellow-fever neutralizing antibodies in 53 SOT recipients vaccinated prior to transplantation (including 29 kidney recipients and 18 liver recipients). All but one (98%) had protective titers of antibodies after a median…

Центры вакцинации от желтой лихорадки: параллельные прививки и обновление биологии комаров.

Обязательные посещения центров иммунизации, которые предлагают вакцину от желтой лихорадки для будущих путешественников, были бы полезны для ознакомления с основами биологии комаров, вызывающих распространение желтой лихорадки. Знания до путешествия в дневное время, а не ночная привычка кусать комаров видов эдес, предотвратит укусы комаров, ответственных за распространение вирусов, вызывающих желтую лихорадку, денге или инфекцию Чикунгунья.

Совпадение в аннотации оригинала
Mandatory visits to immunization centers that offer pre-travel Yellow fever vaccine to prospective travelers would be useful for briefing the basics of the biology of the mosquito responsible for Yellow fever spread. Pre- travel knowledge on the day-time rather the nocturnal biting habit of the mosquitoes of Aedes species would prevent from bites of the mosq…

Evaluation of chimeric yellow fever 17D/dengue viral replication in ticks.

Chimeric yellow fever 17D/DENV-1-4 viruses (CYD-1-4) have been developed as a tetravalent dengue vaccine candidate which is currently being evaluated in efficacy trials in Asia and America. While YF 17D and DENV are mosquito-borne flaviviruses, it has been shown that CYD-1-4 do not replicate after oral infection in mosquitoes and are not transmitted to new hosts. To further document the risk of environmental dissemination of these viruses, we evaluated the replication of CYD-1-4 in ticks, the vector of tick-borne encephalitis virus (TBEV), another member of the flavivirus family. Females of tw…

Using next generation sequencing to identify yellow fever virus in Uganda.

In October and November 2010, hospitals in northern Uganda reported patients with suspected hemorrhagic fevers. Initial tests for Ebola viruses, Marburg virus, Rift Valley fever virus, and Crimean Congo hemorrhagic fever virus were negative. Unbiased PCR amplification of total RNA extracted directly from patient sera and next generation sequencing resulted in detection of yellow fever virus and generation of 98% of the virus genome sequence. This finding demonstrated the utility of next generation sequencing and a metagenomic approach to identify an etiological agent and direct the response to…

Ecdysis triggering hormone signaling in the yellow fever mosquito Aedes aegypti.

At the end of each developmental stage, the yellow fever mosquito Aedes aegypti performs the ecdysis behavioral sequence, a precisely timed series of behaviors that culminates in shedding of the old exoskeleton. Here we describe ecdysis triggering hormone-immunoreactive Inka cells located at branch points of major tracheal trunks and loss of staining coincident with ecdysis. Peptides (AeaETH1, AeaETH2) purified from extracts of pharate 4th instar larvae have--PRXamide C-terminal amino acid sequence motifs similar to ETHs previously identified in moths and flies. Injection of synthetic AeaETHs …

Production of yellow fever virus in microcarrier-based Vero cell cultures.

In this work, the propagation of the 17DD yellow fever virus in Vero cells grown on Cytodex-1 microcarriers was evaluated. After verifying that upon infection the virus adsorption step could be performed under continuous agitation, experiments were carried out in spinners and sparged lab-scale stirred-tank bioreactor to evaluate the use of a commercial serum-free medium (VP-SFM) and to investigate the effects of multiplicity of infection (MOI) and time of infection (TOI) on virus production. Virus titers as high as 8.4 x 10(8)pfu/mL were obtained upon infection with MOI of 0.02 and TOI of 3 da…

NMR assignments of the yellow fever virus envelope protein domain III.

Nearly complete backbone and sidechain resonance assignments have been obtained for the third domain, residues S288-K398, of the envelope protein from the Asibi strain of yellow fever virus using double- and triple-resonance spectroscopy.

Fatal multiorgan failure due to yellow fever vaccine-associated viscerotropic disease.

Yellow fever vaccine-associated viscerotropic disease (YEL-AVD) is a rare complication of yellow fever (YF) vaccination. A previously healthy 22-year-old female died following YF vaccination despite aggressive measures. Serial viral load titers, cytokine levels and host genetic factors were evaluated in an attempt to understand this unusual and lethal outcome. The patient's high-titer vaccine viremia and possibly related minor genetic anomalies provide clues to exploring the etiology of YEL-AVD.

Fatal yellow fever in a traveler returning from Amazonas, Brazil, 2002.

Yellow fever (YF) is a mosquitoborne viral disease that has caused deaths in U.S. and European travelers to sub-Saharan Africa and tropical South America. Although no specific treatment exists for YF and the case-fatality rate for severe YF is approximately 20%, an effective vaccine is available. This report describes a case of fatal YF in an unvaccinated traveler who had returned from a 6-day fishing trip on the Rio Negro west of Manaus in the state of Amazonas, Brazil. Because information from some commercial outfitters and travel agents might underestimate health risks, healthcare providers…

[Antibody responses in Japanese volunteers after immunization with yellow fever vaccine].

To monitor the development of specific and cross-reactive antibody response in twenty Japanese volunteers after vaccination with live yellow fever vaccine. Serum samples were collected on various days after vaccination and examined for hemagglutination inhibition (HI) antibodies against yellow fever virus (YFV), Japanese encephalitis virus (JEV) and dengue virus (DV), neutralizing antibodies against YFV and JEV, and IgM antibodies against YFV. None of the volunteers had been previously immunized with this vaccine. Fifteen of 20 had pre-vaccinated with JEV 7 to 40 years before. Ten of the 20 ha…

Oral susceptibility to yellow fever virus of Aedes aegypti from Brazil.

The oral susceptibility to yellow fever virus was evaluated in 23 Aedes aegypti samples from Brazil. Six Ae. aegypti samples from Africa, America and Asia were also tested for comparison. Mosquito samples from Asia showed the highest infection rates. Infection rates for the Brazilian Ae. aegypti reached 48.6%, but were under 13% in 60% of sample tested. We concluded that although the low infection rates estimated for some Brazilian mosquito samples may not favor the establishment of urban cycle of yellow fever in some parts of the country, the founding of Ae. aegypti of noteworthy susceptibili…

Phylogenetic and evolutionary relationships among yellow fever virus isolates in Africa.

Previous studies with a limited number of strains have indicated that there are two genotypes of yellow fever (YF) virus in Africa, one in west Africa and the other in east and central Africa. We have examined the prM/M and a portion of the E protein for a panel of 38 wild strains of YF virus from Africa representing different countries and times of isolation. Examination of the strains revealed a more complex genetic relationship than previously reported. Overall, nucleotide substitutions varied from 0 to 25.8% and amino acid substitutions varied from 0 to 9.1%. Phylogenetic analysis using pa…

Yellow fever vector live-virus vaccines: West Nile virus vaccine development.

By combining molecular-biological techniques with our increased understanding of the effect of gene sequence modification on viral function, yellow fever 17D, a positive-strand RNA virus vaccine, has been manipulated to induce a protective immune response against viruses of the same family (e.g. Japanese encephalitis and dengue viruses). Triggered by the emergence of West Nile virus infections in the New World afflicting humans, horses and birds, the success of this recombinant technology has prompted the rapid development of a live-virus attenuated candidate vaccine against West Nile virus.

Severe post-vaccination reaction to 17D yellow fever vaccine in Nigeria.

An unusual outbreak of post-vaccination reactions to 17D yellow fever vaccine occurred at Shaki, Nigeria, in May 1987. Twenty-five of the affected people were treated at the Baptist Hospital Shaki. The patients presented with rapidly progressing swelling of the left arm with associated fever and other constitutional symptoms few hours after inoculation with the vaccine. Some of the patients developed gangrene of the affected limb, five of them went into coma and died. Poor hygiene and improper handling of vaccine as well as contamination of vaccine from the source are possible causes. A review…