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A proposed One Health approach to control yellow fever outbreaks in Uganda.

Yellow Fever (YF) is an acute viral hemorrhagic disease. Uganda is located within the Africa YF belt. Between 2019 and 2022, the Ugandan Health Authorities reported at least one outbreak of YF annually with an estimated 892 suspected cases, on average per year. The persistent recurrence of this disease raises significant concerns about the efficacy of current response strategies and prevention approaches. YF has been recognized as a One Health issue due to its interrelatedness with the animal and environmental domains. Monkeys have been recognized as the virus primary reservoir. The YF virus i…

Mechanisms of Flavivirus Cross-Protection against Yellow Fever in a Mouse Model.

The complete lack of yellow fever virus (YFV) in Asia, and the lack of urban YFV transmission in South America, despite the abundance of the peridomestic mosquito vector Aedes (Stegomyia.) aegypti is an enigma. An immunologically naïve population of over 2 billion resides in Asia, with most regions infested with the urban YF vector. One hypothesis for the lack of Asian YF, and absence of urban YF in the Americas for over 80 years, is that prior immunity to related flaviviruses like dengue (DENV) or Zika virus (ZIKV) modulates YFV infection and transmission dynamics. Here we utilized an interfe…

Недостаток коагулирующих факторов связан с кровотечением диатеза острой желтой лихорадки.

Желтая лихорадка (YF) — острая тропическая инфекционная болезнь, вызванная арбовирусом, и может проявляться как классическая геморрагическая лихорадка. Механизм кровоточащего диафеза в YF не вполне понятен. В период с января 2018 года по апрель 2018 года мы провели оценку клинических и лабораторных данных (включая анализы на коагуляцию) по 46 пациентам с умеренными (M) и тяжелыми (S) YF, попавшим в местную больницу. Из 46 пациентов 34 человека получили SYF, из которых 12 (35 процентов) умерли. В общей сложности 21 (45%) пациент получил определенное кровотечение, а 15 (32%) — сильное кровотечен

Совпадение в аннотации оригинала
Yellow fever (YF) is an acute tropical infectious disease caused by an arbovirus and can manifest as a classic hemorrhagic fever. The mechanism of the bleeding diathesis in YF is not well understood. We assessed clinical and laboratory data (including a panel of coagulation tests) from 46 patients with moderate (M) and severe (S) YF admitted to a local hospi…

Safe administration of yellow fever vaccine in patients with suspected egg allergy.

BACKGROUND: The evidence available in the literature on the administration and safety of the yellow fever vaccine in patients with egg allergy is limited. OBJECTIVE: We sought to describe the administration of yellow fever vaccine in children with suspected egg allergy using a simplified protocol. METHODS: Children referred to the service from February 2018 to January 2020 with a history of possible egg allergy were classified as probably egg-allergic or not on the basis of history and specific IgE testing. A vaccine prick test was performed only in those with a history of an anaphylactic re…

A Systematic Review and a Meta-Analysis of the Yellow Fever Vaccine in the Elderly Population.

We conducted a systematic review and a meta-analysis to assess the risk of serious adverse events in the elderly after yellow fever vaccination compared to the non-elderly population. We searched multiple databases and grey literature, and we selected research without language and publication date restrictions. Studies were analyzed in a descriptive way and meta-analyzed and expressed in terms of prevalence ratio and risk ratio with a 95% confidence interval, depending on the degree of heterogeneity found. A total of 18 studies were included and 11 were meta-analyzed. The results obtained thro…

Factors Involved in the Apoptotic Cell Death Mechanism in Yellow Fever Hepatitis.

Yellow fever (YF), a non-contagious infectious disease, is endemic or enzootic to the tropical regions of the Americas and Africa. Periodic outbreaks or epidemics have a significant impact on public health. Programmed cell death, or apoptosis, is generally characterised by distinct morphological changes and energy-dependent biochemical pathways. In this study, we performed immunohistochemistry analysis to identify and quantify proteases and protein targets involved in the cascade that triggers apoptosis in YF virus (YFV)-infected human hepatocytes. Liver tissue samples were collected from 26 i…

Absence of transmission of vYF next generation Yellow Fever vaccine in mosquitoes.

One of the most effective vaccines against an arbovirus is the YFV-17D live-attenuated vaccine developed in 1937 against Yellow Fever (YF). This vaccine replicates poorly in mosquitoes and consequently, is not transmitted by vectors. Vaccine shortages, mainly due to constrained productions based on pathogen-free embryonated eggs, led Sanofi to move towards alternative methods based on a state-of-the-art process using continuous cell line cultures in bioreactor. vYF-247 is a next-generation live-attenuated vaccine candidate based on 17D adapted to grow in serum-free Vero cells. For the developm…

Engineering a self-eliminating transgene in the yellow fever mosquito, Aedes aegypti.

Promising genetics-based approaches are being developed to reduce or prevent the transmission of mosquito-vectored diseases. Less clear is how such transgenes can be removed from the environment, a concern that is particularly relevant for highly invasive gene drive transgenes. Here, we lay the groundwork for a transgene removal system based on single-strand annealing (SSA), a eukaryotic DNA repair mechanism. An SSA-based rescuer strain (kmoRG ) was engineered to have direct repeat sequences (DRs) in the Aedes aegypti kynurenine 3-monooxygenase (kmo) gene flanking the intervening transgenic ca

Genomic diversity contributes to the neuroinvasiveness of the Yellow fever French neurotropic vaccine.

Mass vaccination with the live attenuated vaccine YF-17D is the current way to prevent infection with Yellow fever virus (YFV). However, 0.000012-0.00002% of vaccinated patients develop post-vaccination neurological syndrome (YEL-AND). Understanding the factors responsible for neuroinvasion, neurotropism, and neurovirulence of the vaccine is critical for improving its biosafety. The YF-FNV vaccine strain, known to be associated with a higher frequency of YEL-AND (0.3-0.4%) than YF-17D, is an excellent model to study vaccine neuroinvasiveness. We determined that neuroinvasiveness of YF-FNV occu…

Reemergence of Yellow Fever in Brazil: The Role of Distinct Landscape Fragmentation Thresholds.

Yellow Fever Virus (YFV) reemergence in Brazil was followed by human suffering and the loss of biodiversity of neotropical simians on the Atlantic coast. The underlying mechanisms were investigated with special focus on distinct landscape fragmentation thresholds in the affected municipalities. An ecological study in epidemiology is employed to assess the statistical relationship between events of YFV and forest fragmentation in municipal landscapes. Negative binomial regression model showed that highly fragmented forest cover was associated with an 85% increase of events of YFV in humans and …

The incidence and mortality of yellow fever in Africa: a systematic review and meta-analysis.

BACKGROUND: Understanding the occurrence of yellow fever epidemics is critical for targeted interventions and control efforts to reduce the burden of disease. We assessed data on the yellow fever incidence and mortality rates in Africa. METHODS: We searched the Cochrane Library, SCOPUS, MEDLINE, CINAHL, PubMed, Embase, Africa-wide and Web of science databases from 1 January 1975 to 30th October 2020. Two authors extracted data from included studies independently and conducted a meta-analysis. RESULTS: Of 840 studies identified, 12 studies were deemed eligible for inclusion. The incidence of …

Comparing immunogenicity and protective efficacy of the yellow fever 17D vaccine in mice.

The live-attenuated yellow fever 17D (YF17D) vaccine is one of the most efficacious human vaccines and also employed as a vector for novel vaccines. However, in the lack of appropriate immunocompetent small animal models, mechanistic insight in YF17D-induced protective immunity remains limited. To better understand YF17D vaccination and to identify a suitable mouse model, we evaluated the immunogenicity and protective efficacy of YF17D in five complementary mouse models, i.e. wild-type (WT) BALB/c, C57BL/6, IFN-α/β receptor (IFNAR-/-) deficient mice, and in WT mice in which type I IFN signalli…

Health diplomacy across borders: the case of yellow fever and COVID-19.

We provide an overview of disease control across borders through the example of yellow fever, exploring different public health interventions and arrangements for international cooperation. From quarantine to country vaccine entry requirements our paper discusses the implications for health diplomacy in the context of COVID-19.

An updated antennal lobe atlas for the yellow fever mosquito Aedes aegypti.

The yellow fever mosquito Aedes aegypti is a prolific vector of arboviral and filarial diseases that largely relies on its sense of smell to find humans. To facilitate in-depth analysis of the neural circuitry underlying Ae. aegypti olfactory-driven behaviors, we generated an updated in vitro atlas for the antennal lobe olfactory brain region of this disease vector using two independent neuronal staining methods. We performed morphological reconstructions with replicate fixed, dissected and stained brain samples from adult male and female Ae. aegypti of the LVPib12 genome reference strain and …

[Jungle yellow fever with positive serology for leptospira in a young peruvian male].

Yellow fever (YF) and leptospirosis are under-diagnosed endemic zoonoses of the tropical regions of Africa and South America. Both may be clinically indistinguishable and present as an acute icterohemorrhagic febrile syndrome. We report the case of a 20-year-old male from the department of Amazonas who presented with nine days of disease characterized by multiorgan failure (neurological, renal, hepatic, respiratory, and hematological involvement). He received antibiotic treatment, as well as, transfusion, dialysis, hemodynamic, and ventilatory support. Despite the severity of the clinical cond…

Duration of immunity in recipients of two doses of 17DD yellow fever vaccine.

Antibody levels following yellow fever vaccination (YFV) decrease considerably with time, leaving a substantial proportion of single-dose recipients seronegative after 10 years. Little is known about the persistence of immunity after two or more doses of the vaccine. This study was designed to verify the current immune status of adults who had received two or more doses of YFV. A cross-sectional study assessed the immune status for yellow fever according to time since the latest YFV: second dose at 30-45 days (reference group), 1-5 years, 6-9 years and 10 years or more; and three or more doses…