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Isolation and characterization of wild type yellow fever virus in cases temporally associated with 17DD vaccination during an outbreak of yellow fever in Brazil.

A mass vaccination was carried out in the state of Minas Gerais, Southeast region of Brazil, to control an outbreak of sylvatic yellow fever in 2001. During the outbreak the surveillance system identified two fatal cases temporally associated with YF vaccination. Virus recovered from blood and postmortem samples of both cases was identified as yellow fever virus. Partial nucleotide sequence of parts of prM/E and the non-structural (NS) 5 genes and 3' non-coding region (3' NCR) was employed to characterize the origin of yellow fever virus (YFV) involved in both cases. Wild-type YFV was identifi…

ETIOLOGY OF YELLOW FEVER : IV. THE ACQUIRED IMMUNITY OF GUINEA PIGS AGAINST LEPTOSPIRA ICTEROIDES AFTER THE INOCULATION OF BLOOD OF YELLOW FEVER PATIENTS.

The majority of guinea pigs inoculated with the blood of yellow fever patients escaped a fatal infection. There were a number of instances in which the inoculation of yellow fever blood induced in these animals a temporary febrile reaction on the 4th or 5th day, followed in some cases by slight jaundice, but with a rapid return to normal. Most of these guinea pigs when later inoculated with an organ emulsion of a passage strain of Leptospira icteroides resisted the infection. On the other hand, the animals which had previously been inoculated with the blood of malaria patients or normal guinea…

Entomological investigations into yellow fever outbreak in northern Ghana.

Arboviruses are pathogens of emerging/re-emerging infectious diseases. Half the world's population is at risk. Recent African epidemics confirmed 19,569 cases with 820 deaths. In Ghana, Savannah Region had yellow fever (YF) outbreak in 2021. Reports revealed 35 deaths, 202 suspected cases (case fatality rate (CFR) = 17%), and 70 confirmed cases (CFR = 50%). This paper presents YF outbreak entomological investigations findings. A team with expertise in YF outbreak response were assembled and tasked to assess, contain and/or control the rapid spread of YF. Immature Aedes aegypti were collected i…

Pulmonary Complications in Fatal Yellow Fever, Brazil, 2017-2019.

Yellow fever (YF) mainly causes severe hepatitis; data on pulmonary pathology remain limited. We investigated respiratory tract pathology in 73 fatal YF cases during the 2017-2019 epidemic in São Paulo, Brazil. All patients died from YF-related fulminant hepatitis. Autopsies revealed frequent tracheitis (91%), pulmonary edema and hemorrhage (100%), diffuse alveolar damage (84%), secondary pneumonia (84%), and bronchoaspiration (60%). Microabscesses, thrombi, and hemophagocytosis were also observed. In 5 cases of vaccine-associated viscerotropic disease, hemorrhage and diffuse alveolar damage w…

Оценка Сильватических Желтых Векторов в Южной Бразилии.

Желтая лихорадка (YF) — инфекционное заболевание, вызванное вирусом желтой лихорадки (YFV) — арбовирусом семьи Флавивириде. Она передается через укус зараженных комаров семьи Куличида и затрагивает как людей, так и нечеловеческих приматов. Цель этого исследования состояла в том, чтобы изучить сильватическую фауну куликиды и естественную инфекцию YFV в микрорегионе южной части Санта-Катарины, Бразилия, в районе, недавно затронутом сильватической вспышкой YF. В период с января по февраль 2023 года в пяти муниципалитетах с подтвержденным вирусным распространением были проведены энтомологические с

Совпадение в аннотации оригинала
Yellow fever (YF) is an infectious disease caused by the yellow fever virus (YFV), an arbovirus of the Flaviviridae family. It is transmitted through the bite of infected mosquitoes of the Culicidae family and affects both humans and non-human primates (NHPs). This study aimed to investigate the sylvatic Culicidae fauna and the occurrence of natural YFV infe…

Low-Dose Yellow Fever Vaccine in Adults in Africa.

BACKGROUND: Yellow fever vaccine is highly effective with a single dose, but vaccine supply is limited. The minimum dose requirements for seroconversion remain unknown. METHODS: In this double-blind, randomized, noninferiority trial in Uganda and Kenya, we assigned adults with no history of yellow fever vaccination or infection to receive vaccination with the Institut Pasteur de Dakar 17D-204 yellow fever vaccine at a standard dose (13,803 IU) or at a fractional dose of 1000 IU, 500 IU, or 250 IU. The primary outcome was seroconversion at 28 days after vaccination with each fractional dose as…

Yellow Fever Virus Bank Production in Stationary Cell Culture.

The standardization of trials in both basic and applied research plays a crucial role in ensuring reliability and reproducibility of dataset … ucibility in both testing and product development. This chapter presents a protocol for producing a yellow fever virus (YFV) bank derived from a batch of YFV 17DD vaccine manufactured at Bio-Manguinhos, using stationary culture of Vero CCL-81 cells. Once established, this virus bank can be applied in plaque assays, YFV surveillance studies, diagnostics, and va …

Electron transport chain capacity expands yellow fever vaccine immunogenicity.

Vaccination has successfully controlled several infectious diseases although better vaccines remain desirable. Host response to vaccination … known correlate of antibody response, we found that in healthy volunteers with no detectable or low yellow fever 17D viremia, metformin-treated volunteers elicited higher neutralizing antibody titers than placebo-treated volunteers. Transcriptional and metabolomic analyses collectively showed that a brief course of metformin, started 3 days prior to YF17D vacc …

Understanding yellow fever-associated myocardial injury: an autopsy study.

BACKGROUND: Yellow fever (YF) is a viral hemorrhagic fever, endemic in parts of South America and Africa. There is scarce evidence about the pathogenesis of the myocardial injury. The objective of this study is to evaluate the cardiac pathology in fatal cases of YF. METHODS: This retrospective autopsy study included cases from the São Paulo (Brazil) epidemic of 2017-2019. We reviewed medical records and performed cardiac tissue histopathological evaluation, electron microscopy, immunohistochemical assays, RT-qPCR for YF virus (YFV)-RNA, and proteomics analysis on inflammatory and endothelial …

Systematic review: Yellow fever control through environmental management mechanisms.

OBJECTIVE: Recent research on mosquito vector-borne diseases points to the possibility for a re-emergence of yellow fever. This study investigated attempts at utilising environmental methods and their efficacy for the control of yellow fever and its main vector, Aedes aegypti. METHODS: Potentially eligible studies were searched in Cochrane Library (Reviews and Trials), the Global Index Medicus (encompassing thus the African Index Medicus, the Index Medicus for the Eastern Mediterranean Region, the Index Medicus for the South-East Asia Region, the Latin America and the Caribbean Literature on …

Seroconversion of rheumatoid arthritis patients after yellow fever vaccination.

Vaccination is a current strategy used to prevent infections in patients with immune-mediated rheumatic diseases. However, the use of live-attenuated vaccines prepared from living microorganisms in these patients should be avoided due to the risk of acquiring infections. The present study aimed to investigate the effect of the yellow fever (YF) vaccine (a live-attenuated vaccine) in 12 patients with rheumatoid arthritis (RA). The sample comprised 12 patients (9 females and 3 males; mean age 52.2 ± 6.5 years) with RA, who inadvertently received fractionated 17D yellow fever vaccination during a…

Yellow fever vaccine protects mice against Zika virus infection.

Zika virus (ZIKV) emerged as an important infectious disease agent in Brazil in 2016. Infection usually leads to mild symptoms, but severe congenital neurological disorders and Guillain-Barré syndrome have been reported following ZIKV exposure. Creating an effective vaccine against ZIKV is a public health priority. We describe the protective effect of an already licensed attenuated yellow fever vaccine (YFV, 17DD) in type-I interferon receptor knockout mice (A129) and immunocompetent BALB/c and SV-129 (A129 background) mice infected with ZIKV. YFV vaccination provided protection against ZIKV, …

Yellow fever vaccination for immunocompromised travellers: unjustified vaccination hesitancy?

Improved quality of life in immunocompromised patients opens travel opportunities, but administering the yellow fever (YF) vaccine is often contraindicated. We advocate re-evaluating this position for immunocompromised patients who travel frequently or who are migrating to regions in which YF is endemic.

Host-Specific NS5 Ubiquitination Determines Yellow Fever Virus Tropism.

The recent yellow fever virus (YFV) epidemic in Brazil in 2017 and Zika virus (ZIKV) epidemic in 2015 serve to remind us of the importance of flaviviruses as emerging human pathogens. With the current global flavivirus threat, there is an urgent need for antivirals and vaccines to curb the spread of these viruses. However, the lack of suitable animal models limits the research questions that can be answered. A common trait of all flaviviruses studied thus far is their ability to antagonize interferon (IFN) signaling so as to enhance viral replication and dissemination. Previously, we reported …