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Yellow fever virus infection alters mitochondrial network dynamics and trigger IFN-I response via TLR2 pathway.

It has been emphasized that mitochondria play a fundamental role not only in cellular bioenergetics but also in the defense against infections. Here, we investigated mitochondrial network dynamics (MND) and IFN-Iβ signaling response in epithelial A549 cells after yellow fever virus (YFV) infection. We analyze the MND when only some cells are infected at 1 day post-infection (dpi) and after the spread of viral infection, at 3 dpi. Confocal microscopy and MiNA analysis showed that YFV infection leads to a decrease in the number of branches at 3 dpi and an increase in the length of branches at 1 …

Pharmacovigilance assessment of adverse events following yellow fever vaccination: Disproportionality analysis of VAERS reports, 2015-2025.

Yellow fever vaccination remains the most effective strategy for preventing infection in endemic and travel-associated settings, yet rare severe adverse events such as viscerotropic and neurotropic disease continue to raise safety concerns. Adverse event reports submitted to the Vaccine Adverse Event Reporting System (VAERS) between 2015 and 2025 were analyzed. Disproportionality algorithms were applied to evaluate reporting patterns, with subgroup analyses by age and sex. The most frequent events were local injection-site reactions and mild systemic symptoms, consistent with clinical trial fi…

Potent Monoclonal Antibodies Against Circulating Yellow Fever Virus Strains from Donors Immunized with the 17D Vaccine.

Yellow fever (YF) causes approximately 50,000 deaths annually worldwide and is transmitted by infection with the yellow fever virus (YFV), which is endemic in Sub-Saharan Africa and tropical South America. The live-attenuated YFV 17D vaccine, developed in 1937, is essential to control YFV transmission, but the finite shelf life and manufacturing constraints of egg-based vaccine production, the rare but severe adverse events, and the lack of effective therapeutic options for YF disease highlight the need for new YFV vaccines and therapies. Potent YFV antibodies that neutralize circulating strai…

Plaque reduction neutralization test (PRNT50) for the detection of anti-yellow fever antibodies from clinical samples.

Yellow fever (YF) is a mosquito-borne viral haemorrhagic disease that remains endemic in parts of South America and Africa. Although there is a safe and effective vaccine that has been available for over 75 years, YF remains a public health problem in areas with endemic as well as sporadic transmission. Immune responses elicited by natural infection with yellow fever virus and vaccination are marked by production of neutralizing antibodies. Serological cross-reactivity exhibited by flaviviruses poses challenges to the diagnostic tests for detection of YF-specific antibodies. The most specific …

Yellow fever neutralizing antibody seroprevalence proportion and titers in previously vaccinated adults with chronic kidney disease.

Studies on yellow fever vaccine (YF) in chronic kidney disease (CKD) patients are scarce. This cross-sectional study aimed to evaluate YF neutralizing antibody seroprevalence and titers in previously vaccinated adults with CKD, on dialysis (D-CKD) or not (ND-CKD), compared to healthy persons. The micro Plaque Reduction Neutralization-Horseradish Peroxidase (μPRN-HP) test was used. Antibody titers were expressed as the reciprocal of the highest dilution that neutralized the challenge virus by 50 % (μPRN50). Seropositivity cut-off was set at ≥ 1:100. We included 153 participants: 46 ND-CKD, 50 D…

Обнаружение вирусов панжелтой лихорадки и определение их родства в режиме реального времени по секвенированию RT-PCR и ампликону.

Заболевание желтой лихорадки — вирусный зооноз, который может привести к серьезной геморрагической болезни. Безопасная и эффективная вакцина, используемая в рамках кампаний массовой иммунизации, позволила контролировать и смягчать последствия вспышек взрывчатых веществ в эндемических районах. С 1960-х годов вновь появился вирус желтой лихорадки. Своевременное осуществление мер контроля, с тем чтобы предотвратить или сдержать продолжающуюся вспышку, требует оперативных конкретных методов обнаружения вирусов. Здесь описывается новый молекулярный анализ, который, как ожидается, позволит обнаружит

Совпадение в аннотации оригинала
Yellow fever disease is a viral zoonosis that may result in a severe hemorrhagic disease. A safe and effective vaccine used in mass immunization campaigns has allowed control and mitigation against explosive outbreaks in endemic areas. Since the 1960's, re-emergent of the yellow fever virus has been observed. The timely implementation of control measures, to…

Yellow Fever Disease: Pattern of Presentation of Patients in Federal Medical Centre, Asaba, Delta State, Nigeria.

BACKGROUND: Yellow fever has become a re-emerging disease of public health importance, especially in endemic areas like Nigeria and South America. Since 2017, Nigeria has been riddled with yearly outbreaks of the disease despite the availability of a safe and effective vaccine which was introduced into the country's Expanded Programme on Immunization in 2004. We aim to describe the presentation pattern of patients with the disease who were managed in the 2020 outbreak that occurred in Delta State. METHODS: Data were collected from the case notes of 27 patients managed for the disease using a …

YF17D-vectored Ebola vaccine candidate protects mice against lethal surrogate Ebola and yellow fever virus challenge.

Ebola virus (EBOV) and related filoviruses such as Sudan virus (SUDV) threaten global public health. Effective filovirus vaccines are availa … V-EBOV) in interferon-deficient (Ifnar-/-) mice as surrogate challenge model. Concomitantly induced yellow fever virus (YFV)-specific immunity protected Ifnar-/- mice against intracranial YFV challenge. YF-EBO could thus help to simultaneously combat both EBOV and YFV epidemics. Finally, we demonstrate how to target other highly pathogenic filoviruses such as …

Enhancing Inactivated Yellow Fever 17D Vaccine-Induced Immune Responses in Balb/C Mice Using Alum/CpG.

There are some concerns about the safety of live attenuated yellow fever vaccines (YF-live), particularly viscerotropic adverse events, which have a high mortality rate. The cellular production of the vaccine will not cause these adverse effects and has the potential to extend applicability to those who have allergic reactions, immunosuppression, and age. In this study, inactivated yellow fever (YF) was prepared and adsorbed with Alum/CpG. The cellular and humoral immunities were investigated in a mouse model. The results showed that Alum/CpG (20 μg/mL) could significantly increase the binding…

Phylogenetic analysis reveals a new introduction of Yellow Fever virus in São Paulo State, Brazil, 2023.

Yellow Fever (YF) is a viral arbovirosis of Public Health importance. In Brazil, surveillance is focused mainly on detecting epizootic events of Platyrrhini. Herein, we compared the detection and phylogenetic analysis of YF virus in two neotropical primates (NTP), a Callithrix detected in the previous epidemic period (2016-2020), and a Callicebus nigrifons, showing a new introduction of YF in 2023. This paper illustrates the importance of joint actions of laboratory and field teams to ensure quick response to Public Health emergencies, such as the intensification of vaccination of susceptible …

Neurovirulence, viscerotropism and immunogenicity of live attenuated yellow fever 17D vaccine virus in non-human primates.

Yellow fever vaccine associated neurovirulence and viscerotropism have been reported by various countries. In this study, the neurovirulence, viscerotropism and immunogenicity of yellow fever vaccine seed lots (master and working) and final product manufactured at Serum Institute of India (SII) were evaluated in cynomolgus monkeys. WHO reference virus 168-73 and Stamaril™ as a control vaccine was used for comparison. Neurovirulence and viscerotropism scores of the seed lots and final product were lower than Stamaril™. The SII seed virus and vaccine complies to the WHO requirement for neuroviru…

Diagnostic Specificity of Two Dengue Virus IgG ELISAs after Yellow Fever and Japanese Encephalitis Virus Vaccination.

Dengue virus (DENV) antibody assays frequently cross-react with sera from individuals who have been infected with or vaccinated against related flaviviruses. The goal of this study was to determine the specificity of two DENV ELISAs with sera from individuals vaccinated against yellow fever virus (YFV) and Japanese encephalitis virus (JEV). The Panbio and the Novatec Dengue IgG ELISAs were tested with sera obtained 3-4 weeks or 0.5-6 years after YFV or JEV vaccination and the diagnostic specificity of the assays was determined. As controls, the sera were tested using DENV, YFV, JEV, Zika and W…

Auto-antibodies to type I IFNs can underlie adverse reactions to yellow fever live attenuated vaccine.

Yellow fever virus (YFV) live attenuated vaccine can, in rare cases, cause life-threatening disease, typically in patients with no previous history of severe viral illness. Autosomal recessive (AR) complete IFNAR1 deficiency was reported in one 12-yr-old patient. Here, we studied seven other previously healthy patients aged 13 to 80 yr with unexplained life-threatening YFV vaccine-associated disease. One 13-yr-old patient had AR complete IFNAR2 deficiency. Three other patients vaccinated at the ages of 47, 57, and 64 yr had high titers of circulating auto-Abs against at least 14 of the 17 indi…

Next generation live-attenuated yellow fever vaccine candidate: Safety and immuno-efficacy in small animal models.

Yellow fever (YF) remains a threat to human health in tropical regions of Africa and South America. Live-attenuated YF-17D vaccines have proven to be safe and effective in protecting travellers and populations in endemic regions against YF, despite very rare severe reactions following vaccination - YF vaccine-associated viscerotropic disease (YEL-AVD) and neurological disease (YEL-AND). We describe the generation and selection of a live-attenuated YF-17D vaccine candidate and present its preclinical profile. Initially, 24 YF-17D vaccine candidate sub-strains from the Stamaril® and YF-VAX® line…

Laboratory capacity assessments in 25 African countries at high risk of yellow fever, August-December 2018.

INTRODUCTION: accurate and timely laboratory diagnosis of yellow fever (YF) is critical to the Eliminate Yellow Fever Epidemics (EYE) strategy. Gavi, the Vaccine Alliance recognized the need to support and build capacity in the national and regional laboratories in the Global YF Laboratory Network (GYFLN) as part of this strategy. METHODS: to better understand current capacity, gaps and needs of the GYFLN laboratories in Africa, assessments were carried out in national and regional reference laboratories in the 25 African countries at high risk for YF outbreaks that were eligible for new fina…

Knowledge, Attitude, and Practice of Jinka University Students About Yellow Fever, Ethiopia: A Cross-Sectional Study.

BACKGROUND: Yellow fever (YF) is endemic in South Omo area of Ethiopia. Although Jinka University (JKU) is located in South Omo Zone, there is no information regarding the level of knowledge, attitude, and practice of students toward YF. The current study aimed to assess knowledge, attitude, and practice of JKU students toward YF and factors associated with the overall knowledge and attitude about the disease. METHODS: In this cross-sectional study, a semi-structured self-administered questionnaire was used to collect data from randomly selected regular program JNU students. Data were analyze…

Simultaneous detection of Dengue virus, Chikungunya virus, Zika virus, Yellow fever virus and West Nile virus.

Although certain mosquito-borne virus, such as Dengue virus (DENV), Chikungunya virus (CHIKV), Zika virus (ZIKV), Yellow fever virus (YFV) and West Nile virus (WNV), are an important public health concern in those countries where transmitter mosquitoes are endemic, several cases of travelers from those endemic countries have been recently reported in Europe. Thus, early diagnosis of these viruses is essential for patient management and adoption of preventive measures. An assay for the simultaneous detection of DENV, CHIKV, ZIKV, YFV and WNV based on a multiplex real-time (RT)-PCR and its usefu…

Molecular determinants of Yellow Fever Virus pathogenicity in Syrian Golden Hamsters: one mutation away from virulence.

Yellow fever virus (Flavivirus genus) is an arthropod-borne pathogen, which can infect humans, causing a severe viscerotropic disease with a high mortality rate. Adapted viral strains allow the reproduction of yellow fever disease in hamsters with features similar to the human disease. Here, we used the Infectious Subgenomic Amplicons reverse genetics method to produce an equivalent to the hamster-virulent strain, Yellow Fever Ap7, by introducing a set of four synonymous and six nonsynonymous mutations into a single subgenomic amplicon, derived from the sequence of the Asibi strain. The result…