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Brazilian recommendations on the safety and effectiveness of the yellow fever vaccination in patients with chronic immune-mediated inflammatory diseases.

BACKGROUND: In Brazil, we are facing an alarming epidemic scenario of Yellow fever (YF), which is reaching the most populous areas of the country in unvaccinated people. Vaccination is the only effective tool to prevent YF. In special situations, such as patients with chronic immune-mediated inflammatory diseases (CIMID), undergoing immunosuppressive therapy, as a higher risk of severe adverse events may occur, assessment of the risk-benefit ratio of the yellow fever vaccine (YFV) should be performed on an individual level. Faced with the scarcity of specific orientation on YFV for this specia…

Current status, challenges and perspectives in the development of vaccines against yellow fever, dengue, Zika and chikungunya viruses.

Emerging and re-emerging viral infections transmitted by insect vectors (arthopode-borne viruses, arbovirus) are a serious threat to global public health. Among them, yellow fever (YFV), dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses are particularly important in tropical and subtropical regions. Although vector control is one of the most used prophylactic measures against arboviruses, it often faces obstacles, such as vector diversity, uncontrolled urbanization and increasing resistance to insecticides. In this context, vaccines may be the best control strategy for arboviral disea…

Repellency of the Origanum onites L. essential oil and constituents to the lone star tick and yellow fever mosquito.

The oregano, Origanum onites L., essential oil (EO) was tested in laboratory behavioural bioassays for repellent activity against Amblyomma americanum (L.) and Aedes aegypti (L.). The O. onites EO was characterised using GC-FID and GC-MS. Carvacrol (75.70%), linalool (9.0%), p-cymene (4.33%) and thymol (1.9%) were the most abundant compounds. At a concentration of 0.413 mg oil/cm2 of filter paper, O. onites EO repelled 100% of the ticks tested and at 0.103 mg oil/cm2 of filter paper, 66.7% of the ticks were repelled. At 0.075 mg oil/cm2 filter paper, thymol repelled 66.7% of the ticks compared

Localization and role of inward rectifier K(+) channels in Malpighian tubules of the yellow fever mosquito Aedes aegypti.

Malpighian tubules of adult female yellow fever mosquitoes Aedes aegypti express three inward rectifier K(+) (Kir) channel subunits: AeKir1, AeKir2B and AeKir3. Here we 1) elucidate the cellular and membrane localization of these three channels in the Malpighian tubules, and 2) characterize the effects of small molecule inhibitors of AeKir1 and AeKir2B channels (VU compounds) on the transepithelial secretion of fluid and electrolytes and the electrophysiology of isolated Malpighian tubules. Using subunit-specific antibodies, we found that AeKir1 and AeKir2B localize exclusively to the basolate…

Theories about the propagation of yellow fever: the scientific debate in the São Paulo press between 1895 and 1903.

This article describes the debate over theories about the propagation of yellow fever in the São Paulo press. Our time span was defined as the period between 1895 and 1903, a time that saw high indices of the disease in Brazil. Documentary research involved mass circulation newspapers in São Paulo and medical journals of the period. The empirical data was collected from the Public Archives of the State of São Paulo and from the library of the Faculdade de Saúde Pública at Universidade de São Paulo. It was observed a clash between theories as to the propagation of yellow fever that revealed a s…

Yellow Fever in Africa: estimating the burden of disease and impact of mass vaccination from outbreak and serological data.

BACKGROUND: Yellow fever is a vector-borne disease affecting humans and non-human primates in tropical areas of Africa and South America. While eradication is not feasible due to the wildlife reservoir, large scale vaccination activities in Africa during the 1940s to 1960s reduced yellow fever incidence for several decades. However, after a period of low vaccination coverage, yellow fever has resurged in the continent. Since 2006 there has been substantial funding for large preventive mass vaccination campaigns in the most affected countries in Africa to curb the rising burden of disease and c…

Оценка риска международного распространения вируса желтой лихорадки: математический анализ вспышки в городе Асунсьон, 2008 год.

Вирус желтой лихорадки (YFV) — вирус, передаваемый противомоскитным путем и эндемический для тропической Африки и Южной Америки, может вызвать крупные вспышки заболеваний в городах. С легкостью международных поездок вспышки в городах могут привести к быстрому распространению и последующей передаче YFV в отдаленных районах. Мы разработали стохастическую мета-модель с разновидно выраженными сценариями трансмиссии, чтобы имитировать глобальное распространение YFV от одной городской вспышки ВИЧ-инфицированных авиаперевозчиков. В ходе моделирования вспышки в 2008 году в Асунсьоне, Парагвай, местные

Совпадение в аннотации оригинала
Yellow fever virus (YFV), a mosquito-borne virus endemic to tropical Africa and South America, is capable of causing large urban outbreaks of human disease. With the ease of international travel, urban outbreaks could lead to the rapid spread and subsequent transmission of YFV in distant locations. We designed a stochastic metapopulation model with spatiotem…

Priming effect of dengue and yellow fever vaccination on the immunogenicity, infectivity, and safety of a tetravalent dengue vaccine in humans.

A dengue vaccine effective against all four serotypes is urgently needed. However, safety and immunogenicity could be affected by prior exposure to flaviviruses. This open, controlled, phase IIa study was conducted in 35 healthy adults who had received monovalent, live attenuated Vero cell-derived dengue vaccine against dengue virus 1 (VDV1) or 2 (VDV2) or yellow fever (YF) vaccine 1 year before or who were flavivirus-naïve. All participants received one subcutaneous injection of tetravalent dengue vaccine (TDV) and were followed for 180 days. Previous vaccination did not increase reactogenici…

Quality improvement in travel medicine: a programme for yellow fever vaccination centres in England, Wales and Northern Ireland.

BACKGROUND: The National Travel Health Network and Centre (NaTHNaC), a United Kingdom public health body, is responsible for designating nearly 3500 Yellow Fever Vaccination Centres (YFVCs) in England, Wales and Northern Ireland (EWNI). In 2005, NaTHNaC established a programme of registration, training, clinical standards and audit for YFVCs following the mandate of International Health Regulations (IHR, 2005). ASSESSMENT OF PROBLEM: Administration of yellow fever (YF) vaccine is complex because of the changing epidemiology of YF and the risk of rare, severe adverse events following vaccinati…

A caspase-like decoy molecule enhances the activity of a paralogous caspase in the yellow fever mosquito, Aedes aegypti.

Caspases are cysteine proteases that play critical roles in apoptosis and other key cellular processes. A mechanism of caspase regulation that has been described in mammals and nematodes involves caspase-like decoy molecules, enzymatically inactive caspase homologs that have arisen by gene duplication and acquired the ability to regulate other caspases. Caspase-like decoy molecules are not found in Drosophila melanogaster, raising the question of whether this type of caspase regulation exists in insects. Phylogenomic analysis of caspase genes from twelve Drosophila and three mosquito species r

Outcome of training on yellow fever surveillance in a South-Western state, Nigeria: implications for improved field implementation.

BACKGROUND: Nigeria is in the process of strengthening yellow fever case-based surveillance with the collection of serum samples among suspected case patients. OBJECTIVE: A training conducted for surveillance officers in the local government areas (LGAs) of Osun State on yellow fever case-based surveillance was assessed to determine its immediate impact on the knowledge of participants. METHODS: The training focused mainly on how to detect and report a suspected case of yellow fever to the national authorities and the reference laboratory. Training materials included the World Health Organiz…

Multivariate discrimination between two cryptic Haemagogus species associated with the transmission of yellow fever virus in the Americas.

Mosquitoes of the genus Haemagogus are important vectors of yellow fever virus and other arboviruses and are the principal reservoirs of these viruses in nature. Haemagogus capricornii and Haemagogus janthinomys are closely related species between which females are morphologically cryptic. A morphometric study of these species was performed on male and female specimens from 14 municipalities in Brazil. Morphometric analyses were able to distinguish females. Multivariate morphometrics may be a useful tool for taxonomic studies of cryptic species in this group.

Larvicidal effects of fungal Meroterpenoids in the control of Aedes aegypti L., the main vector of dengue and Yellow fever.

The mosquito Aedes aegypti is an increasing problem of public health, being the vector responsible for dengue and Yellow Fever in tropical and subtropical regions. The aim of this work was to determine the potential larvicidal activity of a series of meroterpenoids, compounds 1-7, previously obtained fungal secondary metabolites from Penicillium sp., against the third-instar larvae of A. aegypti. The lethal concentrations (LC(50) and LC(90)) of 1-7 were evaluated 24 h after exposure. Dehydroaustin (4) was the most active meroterpenoid in the series, with an LC(50) value of 2.9 ppm, making it a…

Polarized light and oviposition site selection in the yellow fever mosquito: no evidence for positive polarotaxis in Aedes aegypti.

Aquatic insects and insects associated with water use horizontally polarized light (i.e., positive polarotaxis) to detect potential aquatic … izontally polarized light in the selection of oviposition sites in blood-fed, gravid females of the yellow fever mosquito, Aedes aegypti. On the basis of our results we propose that Ae. aegypti is not polarotactic. Thus the yellow fever mosquito is the first known water-associated insect species that does not detect water by means of the horizontally polarized …

Analysis of two imported cases of yellow fever infection from Ivory Coast and The Gambia to Germany and Belgium.

BACKGROUND: Yellow fever remains one of the great burdens for public health in the endemic regions in Africa and South America. The under reporting of yellow fever cases in the respective regions and lack of international interest leads to an underestimation of the constant danger in these areas. Non-vaccinated travelers take a high risk without the effective protection of YFV 17D vaccination. OBJECTIVES: Two YF cases were imported to Europe in the last 4 years. We characterized two yellow fever virus (YFV) isolates from severely infected patients coming back from Africa, Ivory Coast and The …

The effects of yellow fever immunization (17DD) inadvertently used in early pregnancy during a mass campaign in Brazil.

BACKGROUND: This study describes the consequences of the inadvertent immunization of pregnant women during a mass vaccination campaign in the Campinas region of the state of São Paulo, Brazil, in February and March 2000. The study was carried out by the Women's Comprehensive Healthcare Center (CAISM), at the State University of Campinas (UNICAMP). The objective of the study was to evaluate the possible effects of the vaccine on pregnancy and conceptus, and to assess congenital infection resulting from immunization. METHODS: Pregnant women who received the YF vaccine were identified at primary

[A simulation model for the control of the Aedes aegypti, the mosquito vector of dengue and yellow fever, by the crustacean Mesocyclops spp].

OBJECTIVE: A simulation model is presented to show the predation dynamics of Mesocyclops spp. over Aedes aegypti. METHODS: The system is represented through four differential equations. H'(t), quantity of eggs; L'(t), quantity of larvae; A'(t), quantity of adults and C'(t), quantity of copepods. Initially the equations are of the classic predator-prey type, according to Lotka (1924) and Volterra (1926). Then it is modified into a system with functional response for invertebrates, according to Holling. RESULTS: The first system effectively controls and stabilizes the mosquito population, whil

[Microeconomic evaluation of a mass preventive immunisation campaign against meningococcal meningitis and yellow fever in Senegal in 1997].

Large epidemics of group A meningococcal meningitis occurred in 1995 and 1996 in several countries of the Sub-Saharan Africa zone known as t … s reached. In this context of epidemics, notably in Mali, and in front of the risk of resurgence of yellow fever, the Ministry of Health of Senegal decided to conduct mass preventive immunization campaigns in 1997 against meningo- coccal meningitis and yellow fever in the districts located in the eastern part of the country and where emergency vaccination woul …

A genetic correlation between age at pupation and melanization immune response of the yellow fever mosquito Aedes aegypti.

To investigate the evolutionary cost of an immune response, we selected six lines of the mosquito Aedes aegypti for earlier or later pupation and measured the extent to which this selection procedure changed the mosquito's ability to encapsulate and melanize a negatively charged Sephadex bead. After 10 generations of selection, the age at pupation in the two selection regimes differed by about 0.7 days, accompanied by an increase of wing length of the mosquitoes selected for late pupation. Among the mosquitoes that had been selected for early pupation, only 6% had strongly or completely melani