a yellow fever epizootic in zika forest, uganda, during 1972: part 1: virus isolation and sentinel monkeys.the results of the yellow fever immunity survey of central and east africa reported by sawyer & whitman in 1936 prompted scientists to undertake well-planned epidemiological studies on yellow fever in eastern africa. a yellow fever research institute (the present east african virus research institute) was established at entebbe in 1936 for this purpose. one of the areas where much work has been carried out is a strip of typical tropical forest, the zika forest, 12 kilometres from the institute. ...1977407675
serological reactions in rhesus monkeys inoculated with the 17d strain of yellow fever virus.haemagglutination-inhibition tests, which depend on the appearance of haemagglutination-inhibiting antibodies in the serum in virus infections, are in common use in the study of arthropod-borne diseases. this paper contains the results of an investigation into the appearance and pattern of haemagglutination-inhibiting antibodies in the serum of rhesus monkeys inoculated intracerebrally with the 17d strain of yellow fever virus during the testing of seed lots of yellow fever vaccine. these antibo ...196213950709
the incubation period of yellow fever in the mosquito.1. the yellow fever virus was found in infectious form in aedes aegypti throughout the entire period of the extrinsic incubation, as demonstrated by the injection of the bodies of mosquitoes into normal rhesus monkeys at daily intervals after the insects had fed on an infected animal. 2. the virus was transmitted through the bite of the mosquitoes, in one experiment on and after the 9th day, and in two experiments on the 12th day after the initial infecting feed. 3. the pathologic changes produc ...192819869467
possibility of hereditary transmission of yellow fever virus by aedes aegypti (linn.).attempts to obtain passage of yellow fever virus from one generation to the next in a. aegypti were unsuccessful. subcutaneous injections at varying intervals of a saline emulsion of 200 eggs laid by an infective lot of mosquitoes produced no reaction in six normal m. rhesus monkeys. negative results were also obtained in five biting and two injection experiments with progeny of the same infective lot of mosquitoes in which seven normal monkeys were used. the eggs consisted of batches laid after ...192919869656
pathophysiologic and transcriptomic analyses of viscerotropic yellow fever in a rhesus macaque model.infection with yellow fever virus (yfv), an explosively replicating flavivirus, results in viral hemorrhagic disease characterized by cardiovascular shock and multi-organ failure. unvaccinated populations experience 20 to 50% fatality. few studies have examined the pathophysiological changes that occur in humans during yfv infection due to the sporadic nature and remote locations of outbreaks. rhesus macaques are highly susceptible to yfv infection, providing a robust animal model to investigate ...201425412185
characterization of yellow fever virus infection of human and non-human primate antigen presenting cells and their interaction with cd4+ t cells.humans infected with yellow fever virus (yfv), a mosquito-borne flavivirus, can develop illness ranging from a mild febrile disease to hemorrhagic fever and death. the 17d vaccine strain of yfv was developed in the 1930s, has been used continuously since development and has proven very effective. genetic differences between vaccine and wild-type viruses are few, yet viral or host mechanisms associated with protection or disease are not fully understood. over the past 20 years, a number of cases ...201627191161
impact of prior flavivirus immunity on zika virus infection in rhesus macaques.studies have demonstrated cross-reactivity of anti-dengue virus (denv) antibodies in human sera against zika virus (zikv), promoting increased zikv infection in vitro. however, the correlation between in vitro and in vivo findings is not well characterized. thus, we evaluated the impact of heterotypic flavivirus immunity on zikv titers in biofluids of rhesus macaques. animals previously infected (≥420 days) with denv2, denv4, or yellow fever virus were compared to flavivirus-naïve animals follow ...201728771605
a flow cytometry-based assay for quantifying non-plaque forming strains of yellow fever virus.primary clinical isolates of yellow fever virus can be difficult to quantitate by standard in vitro methods because they may not form discernable plaques or induce a measurable cytopathic effect (cpe) on cell monolayers. in our hands, the dakar strain of yellow fever virus (yfv-dakar) could not be measured by plaque assay (pa), focus-forming assay (ffa), or by measurement of cpe. for these reasons, we developed a yfv-specific monoclonal antibody (3a8.b6) and used it to optimize a highly sensitiv ...201223028428
distinctive tlr7 signaling, type i ifn production, and attenuated innate and adaptive immune responses to yellow fever virus in a primate reservoir host.why cross-species transmissions of zoonotic viral infections to humans are frequently associated with severe disease when viruses responsible for many zoonotic diseases appear to cause only benign infections in their reservoir hosts is unclear. sooty mangabeys (sms), a reservoir host for siv, do not develop disease following siv infection, unlike nonnatural hiv-infected human or siv-infected rhesus macaque (rm) hosts. siv infections of sms are characterized by an absence of chronic immune activa ...201121515797
the use of yellow fever virus modified by in vitro cultivation for human immunization.the response of rhesus monkeys to a subcutaneous inoculation with varying amounts of virus modified by prolonged cultivation in vitro has been studied. the tissue components of the medium consisted of chick embryo tissue containing minimal amounts of nervous tissue. the immunity produced in monkeys, as measured by the antibody titer developed, has no relation to the amount of virus inoculated. monkeys inoculated subcutaneously with the tissue culture virus are rendered immune to a subsequent inj ...193719870634
the effect of prolonged cultivation in vitro upon the pathogenicity of yellow fever virus.1. experimental evidence is presented to show that prolonged cultivation of yellow fever virus in vitro results in a change in its pathogenicity, and that this change varies with the type of tissues used for the cultivation. 2. in the tissue cultures used for the propagation of the virus, three different types of tissues were used. they included whole mouse embryo, chick embryo from which the head and spinal cord had been removed, and testicular tissues of mice and guinea pigs. 3. the changes in ...193719870633
the titration of yellow fever virus in stegomyia mosquitoes.titrations were made of yellow fever virus in stegomyia mosquitoes, using rhesus monkeys as test animals. it was found that: (a) the average mosquito immediately after engorging on highly infectious blood contained between 1 and 2 million lethal doses of virus. the titer of freshly ingested blood was as high as 1 billion lethal doses of virus per cubic centimeter. (b) during the fortnight succeeding a meal on infectious blood there occurred a reduction of titratable virus to not more than 1 per ...193319870190
the transmission of neurotropic yellow fever virus by stegomyia mosquitoes.1. by the bites of stegomyia mosquitoes carrying neurotropic yellow fever virus, encephalitis has been produced both in white mice and in rhesus monkeys. 2. the fixed neurotropic strain of virus cannot be maintained in the mosquito host as well as can the viscerotropic strains. this is doubtless attributable in part to a smaller amount of virus ingested, because of paucity in the blood stream of the mammalian host. 3. these experiments furnish additional evidence that the long established neurot ...193219870108
the susceptibility of marmosets to yellow fever virus.1. it has been possible to introduce yellow fever virus into the small brazilian monkeys, callithrix albicollis and leontocebus ursulus, by the bites of infected mosquitoes and to carry the virus through a series of four passages in each species and back to rhesus monkeys by the bites of stegomyia mosquitoes fed on the last marmoset of each series. 2. five specimens of l. ursulus were used. four developed fever, and all died during the experiments. at least two showed liver necroses comparable t ...193019869773
the survival of yellow fever virus in cultures.1. the virus of yellow fever has been found to survive in artificial culture media for at least 12 days at a temperature of 35 degrees c. no visible growth has been present and no reproduction of the virus has been demonstrated. 2. infections have been obtained in rhesus monkeys with two strains of virus in quantities as small as 0.00001 cc. of infectious blood, and with one strain in an amount probably as minute as 0.000001 cc.193019869744
the transmission of yellow fever : experiments with the "woolly monkey" (lagothrix lago-tricha humboldt), the "spider monkey" (ateleus ater f. cuvier), and the "squirrel monkey" (saimiri scireus linnaeus).1. saimiri sciureus has been infected with yellow fever virus, both by the inoculation of infectious blood and by the bites of infective mosquitoes. some of the monkeys have died, showing lesions, including hepatic necrosis, suggesting yellow fever as seen in human beings and in rhesus monkeys. virus has been transferred back to m. rhesus from infected saimiri both by blood inoculation and by mosquito bites. the virus undoubtedly has been maintained through four direct passages in saimiri. reino ...193019869721
molecular and phenotypic analysis of a working seed lot of yellow fever virus 17dd vaccine strain produced from the secondary seed lot 102/84 with an additional passage in chicken embryos.over the last 17 years, the yellow fever (yf) 17dd vaccine secondary seed lot 102/84 was used to produce many million doses of vaccine but it was recently used up. in the absence of other lots at the same passage level a large vaccine batch produced from 102/84 was turned into a new working seed. this new seed was characterized with regard to attenuation in the recommended internationally accepted monkey neurovirulence test (mnvt) using the 102/84 virus as reference. all rhesus monkeys (macaca m ...200616326110
uganda s and yellow fever viruses; a slight relationship shown by experiments in rhesus monkeys and white mice. 195313093910
phenotypic and molecular analyses of yellow fever 17dd vaccine viruses associated with serious adverse events in brazil.the yellow fever (yf) 17d virus is one of the most successful vaccines developed to data. its use has been estimated to be over 400 million doses with an excellent record of safety. in the past 3 years, yellow fever vaccination was intensified in brazil in response to higher risk of urban outbreaks of the disease. two fatal adverse events temporally associated with yf vaccination were reported. both cases had features similar to yellow fever disease, including hepatitis and multiorgan failure. t ...200111883195
points to consider in the development of a surrogate for efficacy of novel japanese encephalitis virus vaccines.although an effective killed virus vaccine to prevent illness due to japanese encephalitis virus (jev) infection exists, many authorities recognize that a safe, effective live jev vaccine is desirable in order to reduce the cost and the number of doses of vaccine required per immunization. a large-scale clinical efficacy trail for such a vaccine would be both unethical and impractical. therefore, a surrogate for the efficacy of je vaccines should be established. detection of virus-neutralizing a ...200010821970
chimeric yellow fever virus 17d-japanese encephalitis virus vaccine: dose-response effectiveness and extended safety testing in rhesus monkeys.chimerivax-je is a live, attenuated recombinant virus prepared by replacing the genes encoding two structural proteins (prm and e) of yellow fever 17d virus with the corresponding genes of an attenuated strain of japanese encephalitis virus (je), sa14-14-2 (t. j. chambers et al., j. virol. 73:3095-3101, 1999). since the prm and e proteins contain antigens conferring protective humoral and cellular immunity, the immune response to vaccination is directed principally at je. the prm-e genome sequen ...200010644345
yellow fever virus. i. development and evaluation of a plaque neutralization test.heretofore, the most reliable way of measuring yellow fever virus antibody was to use the mouse neutralization (mn) test employing either suckling or weanling mice. certain disadvantages (e.g., expense both of animals and of maintaining a mouse colony, allergic reactions of many laboratory workers, and the relatively long time, 21 days, before end points are reached) are inherent in any program with mice or other laboratory animal species and have discouraged the use of the mn test by many labor ...19684973067
sensitive and specific monoclonal immunoassay for detecting yellow fever virus in laboratory and clinical specimens.a solid-phase radioimmunoassay (ria) was developed for the detection of yellow fever (yf) virus in infected cell culture supernatant fluid and clinical samples. the test employed a flavivirus group-reactive monoclonal antibody attached to a polystyrene bead support and a radiolabeled type-specific antibody probe in a simultaneous sandwich ria format. optimal assay conditions specified a 16-h incubation at high temperature (45 degrees c). monoclonal antibody to tetanus toxoid was added to the rad ...19863700596
effect of human gamma interferon on yellow fever virus infection.we studied yellow fever virus infection in two species of monkey: saimiri sciureus (squirrel monkeys) and macaca mulatta (rhesus monkeys). human gamma interferon was administered intravenously in five equal doses, one was given 24 hr before infection followed by four doses 24 hr apart. interferon reduced the levels and duration of viremia and the severity of hepatitis in squirrel monkeys. interferon prolonged survival time and delayed the appearance of viremia and hepatitis in infected rhesus mo ...19883152785
the relative resistance of dengue-immune monkeys to yellow fever virus.dengue-immune rhesus monkeys were challenged with a south american and two african strains of yellow fever virus. levels of viremia were reduced as compared with control nonimmunized monkeys. the results support the hypothesis that immunity to dengue in a human population acts as a barrier to establishment of yellow fever in that population.19751111351
serum lactate dehydrogenase of normal, stressed, and yellow fever virus-infected rhesus monkeys.serum lactate dehydrogenase enzyme (sldh) was studied in both healthy and yellow fever virus (yfv)-infected young adult rhesus monkeys (macaca mulatta). in healthy monkeys, significant variation (p less than 0.001) was observed for both total activity and isoenzyme distribution among the following comparisons: individual monkeys, different days, different times of day, and caged versus chair-restrained monkeys (until 7 da after chair restraint). however, variability of baseline values was reduce ...1976820921
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