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Past, present and future distribution of the yellow fever mosquito Aedes aegypti: The European paradox.

The global distribution of the yellow fever mosquito Aedes aegypti is the subject of considerable attention because of its pivotal role as a biological vector of several high profile disease pathogens including dengue, chikungunya, yellow fever, and Zika viruses. There is also a lot of interest in the projected future species' distribution. However, less effort has been focused on its historical distribution, which has changed substantially over the past 100 years, especially in southern Europe where it was once widespread, but largely disappeared by the middle of the 20th century. The present…

Phenotypic and Genetic Studies of the Viral Lineage Associated with the Recent Yellow Fever Outbreak in Brazil.

Yellow fever virus (YFV) caused an outbreak in the Brazilian Southeast from 2016 to 2019, of the most significant magnitude since the 1900s. An investigation of the circulating virus revealed that most of the genomes detected in this period carried nine unique amino acid polymorphisms, with eight located in the non-structural proteins NS3 and NS5, which are pivotal for viral replication. To elucidate the effect of these amino acid changes on viral infection, we constructed viruses carrying amino acid alterations in NS3 and NS5, performed infection in different cells, and assessed their neurovi…

Evaluation of Two Adjuvant Formulations for an Inactivated Yellow Fever 17DD Vaccine Candidate in Mice.

The attenuated yellow fever (YF) vaccine is one of the most successful vaccines ever developed. After a single dose administration YF vaccine can induce balanced Th1/Th2 immune responses and long-lasting neutralizing antibodies. These attributes endorsed it as a model of how to properly stimulate the innate response to target protective immune responses. Despite their longstanding success, attenuated YF vaccines can cause rare fatal adverse events and are contraindicated for persons with immunosuppression, egg allergy and age < 6 months and >60 years. These drawbacks have encouraged the develo…

The production of health news by the press: the context of the coverage of the 2007/2008 yellow fever epidemic.

The COVID-19 pandemic scenario raises the amplification of the debate around the production and circulation of information about epidemics. In this sense, the objective of this article is to discuss how social contexts shape the news, taking as an example the case of the news coverage that transformed an epizootic of yellow fever, in the summer of 2007/2008, into an epidemic of urban yellow fever. This is a qualitative research with journalists who worked in two large circulation newspapers and actively participated in the coverage of the event. The interviews were recorded, transcribed and su…

Categorization by Score of Mosquito Species (Diptera: Culicidae) Related to Yellow Fever Epizootics in Argentina.

The mosquito-borne yellow fever virus (YFV) is the cause of a zoonotic disease, with both sylvatic and urban cycles. Some mosquito species have been associated directly with transmission of the virus in South America, although the importance given to each species varies depending on the bibliography, geographical location, or year of publication. For Argentina, few publications have assessed the involvement of mosquito species, especially those included in the sylvatic cycle. Therefore, the goal of our paper was to gather all the information available in South America and categorize all mosqui…

Delay in health-seeking behaviour: Implication to yellow fever outcome in the 2019 outbreak in Nigeria.

Yellow fever is a vaccine-preventable acute viral disease that can rapidly spread and cause serious public health impact. Delay in seeking health care from health facilities is a potential risk of prolonged disease spread. Therefore, this study assessed the delay in health-seeking behaviour and implications for yellow fever outcomes in the 2019 outbreak in Nigeria. Furthermore, the study examined the factors associated with delayed yellow fever vaccine uptake. A retrospective study was conducted from January to December 2019 using 137 cases recorded in the WHO database. The data were analysed …

Burden is in the eye of the beholder: Sensitivity of yellow fever disease burden estimates to modeling assumptions.

Estimates of disease burden are important for setting public health priorities. These estimates involve numerous modeling assumptions, whose uncertainties are not always well described. We developed a framework for estimating the burden of yellow fever in Africa and evaluated its sensitivity to modeling assumptions that are often overlooked. We found that alternative interpretations of serological data resulted in a nearly 20-fold difference in burden estimates (range of central estimates, 8.4 × 104 to 1.5 × 106 deaths in 2021–2030). Uncertainty about the vaccination status of serological stud…

Shedding of Yellow Fever Virus From an Imported Case in the Netherlands After Travel to Brazil.

We report yellow fever infection in a Dutch traveler returning from Brazil. Yellow fever virus (YFV) was identified in serum and urine samples over a period of 1 month. Yellow fever virus genome sequences from the patient clustered with recent Brazilian YFV and showed with limited nucleotide changes during the resolving infection.

The search for yellow fever virus vaccine in breast milk of inadvertently vaccinated women in Brazil.

Eleven lactating women were inadvertently vaccinated with 17DD yellow fever vaccine in a small city of Sao Paulo State, Brazil. Their infants were being exclusively breast-fed and the breastfeeding was interrupted for 10 days. Serum and breastmilk were collected from the vaccinated mothers and tested for the presence of genomic RNA of the vaccine strain 8, 10 and 15 days after vaccination. Viral RNA was not detected in any of the serum and human milk samples tested and the infants remained asymptomatic. Our result strengthens the effectineness of stopping breastfeeding for 10 days after the in…

A Systematic, Unbiased Mapping of CD8+ and CD4+ T Cell Epitopes in Yellow Fever Vaccinees.

Examining CD8+ and CD4+ T cell responses after primary Yellow Fever vaccination in a cohort of 210 volunteers, we have identified and tetramer-validated 92 CD8+ and 50 CD4+ T cell epitopes, many inducing strong and prevalent (i.e., immunodominant) T cell responses. Restricted by 40 and 14 HLA-class I and II allotypes, respectively, these responses have wide population coverage and might be of considerable academic, diagnostic and therapeutic interest. The broad coverage of epitopes and HLA overcame the otherwise confounding effects of HLA diversity and non-HLA background providing the first ev…

Hormonal regulation of microRNA expression dynamics in the gut of the yellow fever mosquito Aedes aegypti.

The yellow fever mosquito Aedes aegypti is an obligatory blood feeder and a major arboviral disease vector, evoking severe public health concerns worldwide. In adult female mosquitoes, the gut is critical for blood digestion and pathogen entry. We aimed for a systematic exploration of microRNA expression dynamics in the gut during the gonadotrophic cycle. Small RNA libraries were constructed from female mosquito gut tissues at five time points. Unsupervised hierarchical clustering revealed three expression clusters (early, mid and late) peaking at sequential time points - 24, 48 and 72 h poste…

Genetic evidence for the origin of Aedes aegypti, the yellow fever mosquito, in the southwestern Indian Ocean.

Aedes aegypti is among the best-studied mosquitoes due to its critical role as a vector of human pathogens and ease of laboratory rearing. Until now, this species was thought to have originated in continental Africa, and subsequently colonized much of the world following the establishment of global trade routes. However, populations of this mosquito on the islands in the southwestern Indian Ocean (SWIO), where the species occurs with its nearest relatives referred to as the Aegypti Group, have received little study. We re-evaluated the evolutionary history of Ae. aegypti and these relatives, u

Человеческие клетки Шванна подвержены инфекции вирусами Зика и желтой лихорадки, но не вирусом денге.

Вирус Зика (ZIKV) — вновь появившийся аромат, передающийся москитами Aedes spp, который вызвал вспышки лихорадки и сыпи на островах Тихого океана и Северной и Южной Америки. Эти вспышки были связаны с неврологическими осложнениями, включая врожденные аномалии и синдром Гильен-Барре (СГБ). Патогенез связанных с ZIKV ГБС, потенциально опасное для жизни периферийное заболевание нервной системы, остается неясным. Поскольку клетки Шванна (СК) играют центральную роль в периферической нервной функции и могут быть мишенью для повреждения в ГБС, мы охарактеризовали взаимодействие ZIKV из Африки, Азии и

Совпадение в аннотации оригинала
Zika virus (ZIKV) is a re-emerged flavivirus transmitted by Aedes spp mosquitoes that has caused outbreaks of fever and rash on islands in t … ca, Asia and Brazil with human SCs in comparison with the related mosquito-transmitted flaviviruses yellow fever virus 17D (YFV) and dengue virus type 2 (DENV2). SCs supported sustained replication of ZIKV and YFV, but not DENV. ZIKV infection induced increased SC expression of IL-6, interferon (IFN)β1, IFN-λ, IFIT-1, TNFα and IL-23A mRNAs as well as IFN-λ rec …

Immunogenicity and safety of fractional dose yellow fever vaccination: A systematic review and meta-analysis.

BACKGROUND: Recent upsurges in yellow fever outbreaks are increasing the demand for yellow fever vaccine, while enormously straining global vaccine supply. Fractional dose yellow fever vaccination is being considered as a dose-sparing strategy to address current vaccine shortages. This systematic review and meta-analysis aimed to assess the effects of fractional dose yellow fever vaccination, in comparison with those of standard dose vaccination. METHODS: We registered this review on the International Prospective Register of Systematic Reviews (PROSPERO, registration number: CRD42018084214), …

Sero-prevalence of yellow fever and related Flavi viruses in Ethiopia: a public health perspective.

BACKGROUND: Yellow fever (YF) is a viral hemorrhagic fever, endemic in the tropical forests of Africa and Central and South America. The disease is transmitted by mosquitoes infected with the yellow fever virus (YFV). Ethiopia was affected by the largest YF outbreak since the vaccination era during 1960-1962. The recent YF outbreak occurred in 2013 in Southern part of the country. The current survey of was carried out to determine the YF seroprevalence so as to make recommendations from YF prevention and control in Ethiopia. METHODOLOGY: A multistage cluster design was utilized. Consequently,…

Oviposition behavior of Haemagogus leucocelaenus (Diptera: culicidae), a vector of wild yellow fever in Brazil.

Haemagogus leucocelaenus, which is considered a major vector of wild yellow fever, exhibits acrodendrophilic habits and mainly deposits its eggs in treeholes and bamboo internodes. The selection of nursery sites is essential in the life history and reproductive success of mosquitoes. The present work investigated the preferred oviposition height and period of Hg. leucocelaenus in an Atlantic forest area in Rio de Janeiro. Sampling was performed using oviposition traps that were placed on plant material at 0, 2, 4, 6, and 8 m above the ground, from August 2015 to July 2016. Eggs were more abund…

Comparison of the PRNT and an immune fluorescence assay in yellow fever vaccinees receiving immunosuppressive medication.

BACKGROUND: The 17D-yellow fever (YF) vaccination is considered contraindicated in immune-compromised patients; however, accidental vaccination occurs. In this population, measuring the immune response is useful in clinical practice. METHODS: In this study we compare two antibody tests (the Immune Fluorescence Assay and the Plaque Reduction Neutralization Test) in a group of Dutch immune-compromised travellers with a median of 33 days (IQR [28-49]) after primary YF vaccination. RESULTS: We collected samples of 15 immune-compromised vaccinees vaccinated with the 17D yellow fever vaccine betwe…

Прививка от желтой лихорадки во время лечения инфиксимабом у пациента с язвительным колитом.

Мы сообщаем о случае с 59-летним пациентом, который случайно прошел живую вакцинацию от желтой лихорадки во время непрерывного лечения с помощью инфликсимаба TNF-α-антибодиза (AB) от язвительного колита. В ходе клинического курса была продемонстрирована кратковременная лихорадка и возвышение ферментов печени без дополнительных клинических осложнений. Виремия желтой лихорадки не была обнаружена, и были разработаны защитные антитела. В литературе ранее не сообщалось о первичной вакцинации от желтой лихорадки под воздействием инфликсимаба, хотя вакцинация является важной темой в ИБД. Прививки от

Совпадение в аннотации оригинала
We report the case of a 59-year-old patient who accidentally underwent live vaccination against yellow fever during continuous treatment with the TNF-α-antibody (AB) infliximab for ulcerative colitis. The clinical course showed fever of short duration and elevation of liver enzymes without further clinical complications. Yellow fever viremia was not detectab…