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Case Report: Fatal Viscerotropic Disease in a Young Woman Following Yellow Fever Vaccination.

Yellow fever is a viral hemorrhagic disease, and vaccination is the most effective way to minimize the impact of the disease. Serious adverse events after yellow fever vaccination are rare. We report the case of a young woman with an unusual presentation of yellow fever 17DD vaccine-associated acute viscerotropic disease, with severe hepatic impairment following a long incubation period. She died more than a month after yellow fever vaccination.

Dynamics and turnover of memory CD8 T cell responses following yellow fever vaccination.

Understanding how immunological memory lasts a lifetime requires quantifying changes in the number of memory cells as well as how their division and death rates change over time. We address these questions by using a statistically powerful mixed-effects differential equations framework to analyze data from two human studies that follow CD8 T cell responses to the yellow fever vaccine (YFV-17D). Models were first fit to the frequency of YFV-specific memory CD8 T cells and deuterium enrichment in those cells 42 days to 1 year post-vaccination. A different dataset, on the loss of YFV-specific CD8…

Histopathologic Patterns and Susceptibility of Neotropical Primates Naturally Infected With Yellow Fever Virus.

Yellow fever is an important zoonotic viral disease that can be fatal for both human and nonhuman primates. We evaluated histopathologic changes in free-ranging neotropical primates naturally infected with yellow fever virus (YFV) compared with uninfected cohorts. The most frequent lesions in primates infected with YFV were hepatic changes characterized by midzonal necrosis with lipidosis and mild inflammation including lymphocytes, macrophages, plasma cells, and infrequently neutrophils. Importantly, severe necrotizing hepatic lesions were often observed in Alouatta sp. (howler monkeys), wher…

Liver Transplantation for Acute Liver Failure due to Yellow Fever: A Case Report.

Yellow fever is a noncontagious disease caused by an arbovirus in the Flaviviridae family. It is an endemic disease in the tropical forests of Africa and South America, with the mosquito as a vector. Approximately half of those infected will be asymptomatic, while 15% will develop the severe/malignant form of the disease that includes renal and hepatic failure, bleeding, and neurological impairment as the principal symptoms. The lethality of the severe form reaches up to 70%. The objective of this study was to report on the case of a patient who was transferred to the hepatobiliary unit of our…

Fractional-dose yellow fever vaccination: how much more can we do with less?

PURPOSE OF REVIEW: Climate change, deforestation, urbanization, and increased population mobility have made the risk of large outbreaks of yellow fever more likely than ever. Yellow fever vaccine production barely meets demands. In this review, we address the causes of the recent yellow fever outbreaks, why fractional dose yellow fever vaccination works, the role of virus neutralizing antibodies in the protection against yellow fever, and the need for revaccination. RECENT FINDINGS: Human activities have profoundly changed the epidemiology of yellow fever. The excess of infectious viral parti…

Structure-Function of the Yellow Fever Virus Envelope Protein: Analysis of Antibody Epitopes.

Yellow fever virus (YFV) is the prototype member of the genus Flavivirus, which contains more than 60 positive-sense, single-stranded RNA viruses, many of which are considered public health threats. YF disease is controlled by a live attenuated vaccine, 17D, which was generated empirically through serial passage of the wild-type (WT) strain Asibi in chicken tissue. The vaccine, which has been used for over 80 years, is considered to be one of the safest and most effective live attenuated vaccines. It has been shown that the humoral immune response is essential to a positive disease outcome dur…

Generation of Yellow Fever virus vaccine in skeletal muscle cells of chicken embryos.

BACKGROUND: The Yellow Fever (YF) vaccine is produced by the inoculation of embryonated chicken eggs with YF17DD virus on the ninth day of development. Full embryos are collected on the twelfth day of development for vaccine formulation. Skeletal muscle tissue is the main site where biosynthesis of viral particles occurs. OBJECTIVES: This study aimed to analyse the experimental infection of skeletal muscle cells of chicken embryos by the 17DD Yellow Fever virus (YFV) in vivo and in vitro. METHODS: Chicken embryos infected with YF17DD virus were analysed by immunofluorescence using confocal a…

Bacteria-mediated modification of insecticide toxicity in the yellow fever mosquito, Aedes aegypti.

The incidence of mosquito-borne disease poses a significant threat to human and animal health throughout the world, with effective chemical … e insecticides propoxur and naled, as well as the insecticidal activity of these chemistries to the yellow fever mosquito, Aedes aegypti. Experiments conducted using insecticide synergists that reduce general esterase and P450 activity demonstrate a role for both groups of enzymes in the metabolic detoxification of propoxur and naled. Furthermore, reduction of …

Metagenomic analysis reveals Hepatitis A virus in suspected yellow fever cases in Brazil.

Using a metagenomic approach, we identified hepatitis A virus among cases of acute febrile illnesses that occurred in 2008-2012 in Brazil suspected as yellow fever. These findings reinforce the challenge facing routine clinical diagnosis in complex epidemiological scenarios.

Existing and potential infection risk zones of yellow fever worldwide: a modelling analysis.

BACKGROUND: Yellow fever cases are under-reported and the exact distribution of the disease is unknown. An effective vaccine is available but more information is needed about which populations within risk zones should be targeted to implement interventions. Substantial outbreaks of yellow fever in Angola, Democratic Republic of the Congo, and Brazil, coupled with the global expansion of the range of its main urban vector, Aedes aegypti, suggest that yellow fever has the propensity to spread further internationally. The aim of this study was to estimate the disease's contemporary distribution a…

Cutaneous lesions caused by the yellow fever vaccine - have you ever seen them?

The Yellow Fever virus was isolated in 1927 and the disease is considered endemic and epidemic in tropical regions of South America and Africa, with thousands of new cases reported annually. Several side effects of the vaccine have already been reported. Although reports of skin rash secondary to the vaccine range from 0 to 15%, no image or detailed description of the lesions were found in the literature. Here we describe a rash on a toddler vaccinated to travel.

Persistence of yellow fever virus-specific neutralizing antibodies after vaccination among US travellers.

BACKGROUND: Few studies have assessed the duration of humoral immunity following yellow fever (YF) vaccination in a non-endemic population. We evaluated seropositivity among US resident travellers based on time post-vaccination. METHODS: We identified serum samples from US travellers with YF virus-specific plaque reduction neutralization testing (PRNT) performed at CDC from 1988 to 2016. Analyses were conducted to assess the effect of time since vaccination on neutralizing antibody titer counts. RESULTS: Among 234 travellers who had neutralizing antibody testing performed on a specimen obtai…

Yellow Fever Outbreak - Kongo Central Province, Democratic Republic of the Congo, August 2016.

On April 23, 2016, the Democratic Republic of the Congo's (DRC's) Ministry of Health declared a yellow fever outbreak. As of May 24, 2016, approximately 90% of suspected yellow fever cases (n = 459) and deaths (45) were reported in a single province, Kongo Central Province, that borders Angola, where a large yellow fever outbreak had begun in December 2015. Two yellow fever mass vaccination campaigns were conducted in Kongo Central Province during May 25-June 7, 2016 and August 17-28, 2016. In June 2016, the DRC Ministry of Health requested assistance from CDC to control the outbreak. As of Au…

Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults.

INTRODUCTION:: The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged  60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. METHODS:: previously vaccinated healthy p…

Rapid Evolution of Ovarian-Biased Genes in the Yellow Fever Mosquito (Aedes aegypti).

Males and females exhibit highly dimorphic phenotypes, particularly in their gonads, which is believed to be driven largely by differential gene expression. Typically, the protein sequences of genes upregulated in males, or male-biased genes, evolve rapidly as compared to female-biased and unbiased genes. To date, the specific study of gonad-biased genes remains uncommon in metazoans. Here, we identified and studied a total of 2927, 2013, and 4449 coding sequences (CDS) with ovary-biased, testis-biased, and unbiased expression, respectively, in the yellow fever mosquito Aedes aegypti The resul…

Kinetic Study of Yellow Fever 17DD Viral Infection in Gallus gallus domesticus Embryos.

Yellow fever continues to be an important epidemiological problem in Africa and South America even though the disease can be controlled by vaccination. The vaccine has been produced since 1937 and is based on YFV 17DD chicken embryo infection. However, little is known about the histopathological background of virus infection and replication in this model. Here we show by morphological and molecular methods (brightfield and confocal microscopies, immunofluorescence, nested-PCR and sequencing) the kinetics of YFV 17DD infection in chicken embryos with 9 days of development, encompassing 24 to 96…

Вопросы, касающиеся безопасности и продолжительности иммунитета после вакцинации от желтой лихорадки.

Всемирная организация здравоохранения (ВОЗ) и другие учреждения здравоохранения пришли к выводу о том, что вакцинация от желтой лихорадки является ненужной, поскольку одна доза вакцины дает иммунитет на всю жизнь. Охватываемые области: Мы проанализировали клинические исследования, на которые ссылались органы здравоохранения при изучении ими характеристик безопасности и продолжительности иммунитета для вакцины YFV-17D, и изучили позицию, согласно которой более не нужна вакцинация для ускорения. Мы обнаружили, что антивирусная неприкосновенность может быть утрачена у 1 в 3 - 1 в 5 человек в тече

Совпадение в аннотации оригинала
The World Health Organization (WHO) and other health agencies have concluded that yellow fever booster vaccination is unnecessary since a single dose of vaccine confers lifelong immunity. Areas covered: We reviewed the clinical studies cited by health authorities in their investigation of both the safety profile and duration of immunity for the YFV-17D vacci…