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Viscerotropic disease and acute uveitis following yellow fever vaccination: a case report.

BACKGROUND: Yellow fever vaccine exists for over 80 years and is considered to be relatively safe. However, in rare cases it can produce serious neurotropic and viscerotropic complications. We report a case of a patient who presented both viscerotropic and neurological manifestations after yellow fever vaccination. CASE PRESENTATION: We describe the case of a 37 years old man who developed after the yellow fever vaccination a yellow fever vaccine-associated viscerotropic disease followed by acute uveitis. Prolonged detection of yellow fever RNA in blood and urine was consistent with yellow fe…

Genomic evidence of yellow fever virus in Aedes scapularis, southeastern Brazil, 2016.

The southeastern region of Brazil has recently experienced the largest yellow fever disease outbreak in decades. Since July 2016 epizootic events were reported in São Paulo state's north region, where 787 Culicidae were captured as part of public health surveillance efforts and tested using real-time quantitative PCR. One Aedes scapularis pool collected in November 2016 in an agriculture area in Urupês city tested positive for YFV-RNA. Using a validated multiplex PCR approach we were able to recover a complete virus genome sequence from this pool. Phylogenetic analysis of the novel strain and …

Identification of Novel Yellow Fever Class II Epitopes in YF-17D Vaccinees.

Yellow fever virus (YFV) is a mosquito-borne member of the genus flavivirus, including other important human-pathogenic viruses, such as dengue, Japanese encephalitis, and Zika. Herein, we report identifying 129 YFV Class II epitopes in donors vaccinated with the live attenuated YFV vaccine (YFV-17D). A total of 1156 peptides predicted to bind 17 different common HLA-DRB1 allelic variants were tested using IFNγ ELISPOT assays in vitro re-stimulated peripheral blood mononuclear cells from twenty-six vaccinees. Overall, we detected responses against 215 YFV epitopes. We found that the capsid and…

A peridomestic Aedes malayensis population in Singapore can transmit yellow fever virus.

The case-fatality rate of yellow fever virus (YFV) is one of the highest among arthropod-borne viruses (arboviruses). Although historically, the Asia-Pacific region has remained free of YFV, the risk of introduction has never been higher due to the increasing influx of people from endemic regions and the recent outbreaks in Africa and South America. Singapore is a global hub for trade and tourism and therefore at high risk for YFV introduction. Effective control of the main domestic mosquito vector Aedes aegypti in Singapore has failed to prevent re-emergence of dengue, chikungunya and Zika vi…

Yellow Fever Virus: Knowledge Gaps Impeding the Fight Against an Old Foe.

Yellow fever (YF) was one of the most dangerous infectious diseases of the 18th and 19th centuries, resulting in mass casualties in Africa and the Americas. The etiologic agent is yellow fever virus (YFV), and its live-attenuated form, YFV-17D, remains one of the most potent vaccines ever developed. During the first half of the 20th century, vaccination combined with mosquito control eradicated YFV transmission in urban areas. However, the recent 2016-2018 outbreaks in areas with historically low or no YFV activity have raised serious concerns for an estimated 400-500 million unvaccinated peop…

Detection of yellow fever virus genomes from four imported cases in China.

Yellow fever virus (YFV), as the first proven human-pathogenic virus, is still a major public health problem with a dramatic upsurge in recent years. This is a report on four imported cases of yellow fever virus into China identified by whole genome sequencing. Phylogenetic analysis was performed and the results showed that these four viruses were highly homologous with Angola 71 strains (AY968064). In addition, effective mutations of amino acids were not observed in the E protein domain of four viruses, thus confirming the effectiveness of the YFV-17D vaccine (X03700). Although there is low r…

Vaccines and vaccination against yellow fever: WHO Position Paper, June 2013--recommendations.

This article presents the World Health Organizations (WHO) evidence and recommendations for the use of yellow fever (YF) vaccination from "Vaccines and vaccination against yellow fever: WHO Position Paper - June 2013" published in the Weekly Epidemiological Record. This position paper summarizes the WHO position on the use of YF vaccination, in particular that a single dose of YF vaccine is sufficient to confer sustained life-long protective immunity against YF disease. A booster dose is not necessary. The current document replaces the position paper on the use of yellow fever vaccines and vac…

Неммунная активация меняет клеточную и юморальную реакцию на желтую вакцину 17D.

ОКРУЖАЮЩАЯ СРЕДА: Определение параметров, которые позволят двигать вакцины среди африканского населения, будет иметь важнейшее значение для разработки эффективных вакцин для защиты от ВИЧ, малярии, туберкулеза и вирусных инфекций денге. Цель этого исследования состояла в том, чтобы оценить вклад иммунной микроокружающей среды конкретного пациента в реакцию на лицензированную вакцину от желтой лихорадки 17D (YF-17D) в одной из африканских групп. Мы сравнили ответы на YF-17D с 50 добровольцами в Энтеббе, Уганда, и 50 добровольцами в Лозанне, Швейцария. Мы измеряли реакции CD8+T и B клеток, вызва

Совпадение в аннотации оригинала
BACKGROUND: Defining the parameters that modulate vaccine responses in African populations will be imperative to design effective vaccines for protection against HIV, malaria, tuberculosis, and dengue virus infections. This study aimed to evaluate the contribution of the patient-specific immune microenvironment to the response to the licensed yellow fever va…

Subdoses of 17DD yellow fever vaccine elicit equivalent virological/immunological kinetics timeline.

BACKGROUND: The live attenuated 17DD Yellow Fever vaccine is one of the most successful prophylactic interventions for controlling disease expansion ever designed and utilized in larger scale. However, increase on worldwide vaccine demands and manufacturing restrictions urge for more detailed dose sparing studies. The establishment of complementary biomarkers in addition to PRNT and Viremia could support a secure decision-making regarding the use of 17DD YF vaccine subdoses. The present work aimed at comparing the serum chemokine and cytokine kinetics triggered by five subdoses of 17DD YF Vacc…

Dynamic viral dissemination in mice infected with yellow fever virus strain 17D.

Arboviruses such as yellow fever virus (YFV) are transmitted between arthropod vectors and vertebrate hosts. While barriers limiting arbovirus population diversity have been observed in mosquitoes, whether barriers exist in vertebrate hosts is unclear. To investigate whether arboviruses encounter bottlenecks during dissemination in the vertebrate host, we infected immunocompetent mice and immune-deficient mice lacking alpha/beta interferon (IFN-α/β) receptors (IFNAR⁻/⁻ mice) with a pool of genetically marked viruses to evaluate dissemination and host barriers. We used the live attenuated vacci…

Yellow fever virus susceptibility of two mosquito vectors from Kenya, East Africa.

Yellow fever is an unpredictable disease of increasing epidemic threat in East Africa. Aedes (Stegomyia) aegypti has never been implicated as a vector in this region and recent outbreaks have involved a newly emerging virus genotype (East African). To better understand the increasing epidemic risk of yellow fever in East Africa, this study is the first to investigate the vector competence for an emerging East African virus genotype in Kenyan A. aegypti sensu latu (s.l) and A. (Stegomyia) simpsoni s.l. mosquito species. Using first filial generation mosquitoes and a low passage yellow fever vir…

Assessment of yellow fever epidemic risk: an original multi-criteria modeling approach.

BACKGROUND: Yellow fever (YF) virtually disappeared in francophone West African countries as a result of YF mass vaccination campaigns carried out between 1940 and 1953. However, because of the failure to continue mass vaccination campaigns, a resurgence of the deadly disease in many African countries began in the early 1980s. We developed an original modeling approach to assess YF epidemic risk (vulnerability) and to prioritize the populations to be vaccinated. METHODS AND FINDINGS: We chose a two-step assessment of vulnerability at district level consisting of a quantitative and qualitative…

Lymphocyte subset analyses in healthy adults vaccinated with yellow fever 17DD virus.

In this study the kinetics of humoral and cellular immune responses in first-time vaccinees and re-vaccinees with the yellow fever 17DD vaccine virus was analyzed. Flow cytometric analyses were used to determine percentual values of T and B cells in parallel to the yellow fever neutralizing antibody production. All lymphocyte subsets analyzed were augmented around the 30th post vaccination day, both for first-time vaccinees and re-vaccinees. CD3+ T cells increased from 30.8% (SE +/- 4%) to 61.15% (SE +/- 4.2%), CD4+ T cells from 22.4% (SE +/- 3.6%) to 39.17% (SE +/- 2%) with 43% of these cells…

Age-related risk of adverse events following yellow fever vaccination in Australia.

Reports of six deaths internationally, including one from Australia, plus other cases of severe systemic adverse events following yellow fever (YF) vaccination have raised concern about the safety of YF vaccine, particularly among older vaccinees. We investigated the age-related reporting rates of adverse events following YF vaccination reported to the Australian Adverse Drug Reactions Advisory Committee for the period 1993 to 2002. The reporting rate of systemic adverse events leading to hospitalisation or death was significantly higher among vaccinees aged > or = 65 years [reporting rate rat…

Saliva of the Yellow Fever mosquito, Aedes aegypti, modulates murine lymphocyte function.

Saliva of many vector arthropods contains factors that inhibit haemostatic responses in their vertebrate hosts. Less is known about the effect of vector saliva on host immune responses. We investigated the effect of Aedes aegypti salivary gland extracts on antigen-stimulated responses of transgenic OVA-TCR DO11 mouse splenocytes in vitro. T-cell proliferation was inhibited in a dose-dependent manner, with greater than 50% inhibition at 0.3 salivary gland pair (SGP) equivalents/mL. LPS-stimulated B-cell proliferation was also inhibited. Secretion of the Th1 cytokines IL-2 and IFN-gamma was redu

Yellow fever vaccination during pregnancy and spontaneous abortion: a case-control study.

OBJECTIVE: To assess a possible association between Yellow fever (YF) vaccine (inadvertently) administered during early pregnancy and spontaneous abortion. METHOD: A hospital-based case-control study conducted in a Brazilian town after a YF vaccine campaign that followed an epidemic of dengue. The study included 39 women who attended a university hospital with spontaneous abortion (cases) and 74 pregnant women attending the antenatal clinic of that hospital (controls). RESULTS: The crude odds ratio (relative risk estimate) of this association was 2.49, which dropped to 2.29 (95% CI 0.65-8.03…

Yellow fever virus envelope protein has two discrete type-specific neutralizing epitopes.

Two monoclonal antibody neutralization resistant (MAbR) variants of the yellow fever (YF) 17D-204 vaccine virus strain were selected using YF type-specific MAb B39. These B39R variants were compared with the variant virus selected by Lobigs et al. (Virology 161, 474-478, 1987) using a second YF-type specific MAb (2E10) which mapped to amino acid position 71/72 in the envelope (E) protein. Neutralization assays with a panel of MAbs suggested that these two YF-type-specific epitopes are located in two discrete regions of the folded E protein. Each of the B39R variants had a single nucleotide mut…

Encephalitis in a 13-year-old boy following 17D yellow fever vaccine.

We report a case of encephalitis following yellow fever vaccine in a healthy 13 year-old-boy. This is the first reported case in a child older than 3 years of age and the second over the age of 9 months, before which time the vaccine is contraindicated for routine immunisation.

Analysis of 17D yellow fever virus envelope protein epitopes using monoclonal antibodies.

Sixteen monoclonal antibodies that reacted with the envelope glycoprotein (E) of 17D vaccine strain yellow fever virus (17D YF), including two antibodies produced against dengue 2 virus, were used in a solid phase competitive binding assay (CBA) to define spatial relationships among antigenic determinants on 17D YF E. The antibodies showed YF strain, type or flavivirus group specificities and nine epitopes were identified on 17D YF E by patterns of neutralization, haemagglutination inhibition and competition of antibody binding. Epitopes defined by neutralizing antibodies with strain and type …

Glutathione biosynthesis in the aging adult yellow-fever mosquito [Aedes aegypti (Louisville)].

Our previous findings [Hazelton & Lang (1978) Fed. Proc. Fed. Am. Soc. Exp. Biol. 37(6), 2378 (abstr.)] demonstrated a senescence-specific decrease in glutathione (GSH) concentration in the yellow-fever mosquito Aedes aegypti (Louisville)]. As a possible mechanism for this change, GSH biosynthesis was investigated in adult mosquitoes of different ages through the life-span. Biosynthesis was measured as the incorporation rate of [14C]glycine or [14C]cystine into glutathione. Essential information to validate the procedure was also obtained on the precursor-amino-acid pool sizes and kinetic para