| zika virus infections in nigeria: virological and seroepidemiological investigations in oyo state. | a study of zika virus infections was carried out in four communities in oyo state, nigeria. virus isolation studies between 1971 and 1975 yielded two virus isolations from human cases of mild febrile illness. haemagglutination-inhibition tests revealed a high prevalence of antibodies to zika and three other flaviviruses used. the percentages of positive sera were as follows: zika (31%), yellow fever (50%), west nile (46%), and wesselsbron (59%). neutralization tests showed that 40% of nigerians ... | 1979 | 489960 |
| human arthropod-borne virus infections in nigeria. serological and virological investigations and shaki, oyo state. | during the early dry season of 1972, an arbovirus surveillance was carried out is shaki. on hundred and twenty human blood samples and 304 sera were processed for virus isolation and serology respectively. a high prevalence of antibodies to 8 arbovirus antigens was found in the community. percentage of positive sera was as follows: chikungunya (24%) sindbis (19%), yellow fever (55%), dengue (54%), west nile (58%) and wesselsbron (67%). human infections by ilesha virus (35%) and ingwavuma (15%) ... | 1978 | 570581 |
| epidemiological investigations on arbovirus infections at igbo-ora, nigeria. | a study of arbovirus infections occurring in igbo-ora community was carried out between may and october 1975. haemagglutination inhibition test performed on seventy-eight human sera showed a high prevalence of antibodies against all the six arboviruses used. percentage of positive sera were as follows: chikungunya, (28%); yellow fever (36%); dengue type 1 (67%); dengue type 2 (45%). prevalence of hi antibodies to west nile and wesselsbron viruses were 44% and 59% respectively. virus isolation st ... | 1977 | 906078 |
| virus safety of human immunoglobulins: efficient inactivation of hepatitis c and other human pathogenic viruses by the manufacturing procedure. | human immunoglobulins are plasma derivatives with a low risk of transmitting viral infections. to the present, no proven case of human immunoglobulins transmitting human immunodeficiency viruses has been reported. however, there have been a few reports on the transmission of hepatitis c virus by these plasma proteins. to improve further the safety of both 5s iv human immunoglobulins and 7s im immunoglobulins, we introduced a 10-hour heat treatment of the aqueous solutions at 60 degrees c (i.e., ... | 1992 | 1314286 |
| [transfusion-associated non-a, non-b, non-c hepatitis caused by flaviviruses]. | hepatitis c virus was shown to be a member of the flavivirus family. tick-borne encephalitis virus and west nile virus, members of the same family occur in hungary, too. serum samples from patients suffering from transfusion associated hepatitis were tested with yellow fever virus antigens for specific igg, and igm using immunofluorescence test. eight hundred serum samples were tested. yellow fever virus related igg antibodies were found in 232 sera. in the case of 72 patients specific igm antib ... | 1992 | 1321397 |
| dengue virus-specific, human cd4+ cd8- cytotoxic t-cell clones: multiple patterns of virus cross-reactivity recognized by ns3-specific t-cell clones. | thirteen dengue virus-specific, cytotoxic cd4+ cd8- t-cell clones were established from a donor who was infected with dengue virus type 3. these clones were examined for virus specificity and human leukocyte antigen (hla) restriction in cytotoxic assays. six patterns of virus specificities were determined. two serotype-specific clones recognized only dengue virus type 3. two dengue virus subcomplex-specific clones recognized dengue virus types 2, 3, and 4, and one subcomplex-specific clone recog ... | 1991 | 1705990 |
| global climate change and infectious diseases. | the effects of global climate change on infectious diseases are hypothetical until more is known about the degree of change in temperature and humidity that will occur. diseases most likely to increase in their distribution and severity have three-factor (agent, vector, and human being) and four-factor (plus vertebrate reservoir host) ecology. aedes aegypti and aedes albopictus mosquitoes may move northward and have more rapid metamorphosis with global warming. these mosquitoes transmit dengue v ... | 1991 | 1820262 |
| heterologous flavivirus infection-enhancing antibodies in sera of nigerians. | human sera collected from nigerians were examined for plaque reduction neutralizing and infection-enhancing antibodies against dengue 2, yellow fever, and west nile viruses. neutralization tests showed that 17 of 19 sera contained flavivirus neutralizing antibody; 11 were positive to all 3 viruses, 5 to dengue and yellow fever, and 1 to dengue virus only. two sera had no detectable neutralizing antibody to any of the flaviviruses. enhancement assays showed that 17 flavivirus neutralizing antibod ... | 1988 | 2829637 |
| human antibody response to immunization with 17d yellow fever and inactivated tbe vaccine. | the antibody response against flaviviruses tick-borne encephalitis (tbe), kyasanur forest disease (kfd), murray valley encephalitis (mve), west nile fever (wnf), japanese b encephalitis (je), dengue 2 (den-2), and yellow fever (yf) was studied in humans after administration of an inactivated tbe virus vaccine. individuals were either prevaccinated with 17d yellow fever (experimental group) or without any previous exposure to flaviviruses (control group). the appearance of serum titres of homolog ... | 1985 | 2995571 |
| [serological study of the virus responsible for hemorrhagic fever in an urban population of cameroon]. | a sero-epidemiological study of hemorrhagic fever viruses in a urban population of cameroon. the authors report the results of a sero-epidemiological survey undertaken in a urban population of cameroon and concerning congo, rift (rvf), lassa, ebola, marburg and yellow fever viruses. on 375 human sera tested, 1.06% show antibodies against rvf virus and 1.87% are positive for anti-ebola antibodies thus yielding evidence that these two viruses are present in this area of cameroon. 33.75% have antib ... | 1988 | 3064937 |
| flavivirus-cross-reactive, hla-dr15-restricted epitope on ns3 recognized by human cd4+ cd8- cytotoxic t lymphocyte clones. | the role of flavivirus-cross-reactive t lymphocytes in recovery from and pathogenesis of flavivirus infections is not known. in the present paper, we have defined a flavivirus-cross-reactive epitope recognized by two cd4+ cd8- cytotoxic t lymphocyte (ctl) clones, jk4 and jk43. the t cell clones were established from the peripheral blood t lymphocytes of a dengue-4-immune donor, using a limiting-dilution method with dengue-4 antigen. these two t cell clones were cross-reactive for dengue virus ty ... | 1995 | 7561761 |
| [a serological survey regarding flaviviridae infections on the island of réunion (1971-1989)]. | serological prevalence of flaviviridae was studied on reunion island by testing 2,507 human sera from a randomised sample. each serum was tested against 5 viruses (yellow fever, dengue type 1 and 2, west nile and wesselsbron) using haemagglutination inhibition test: 42.68% of human sera were found positive. the multivalent reactions represent practically three fourths of the positive ones. a severe dengue type 2 outbreak on the island in 1977-1978 and the possible circulation of a flavivirus may ... | 1994 | 8061530 |
| surveillance for yellow fever virus in eastern senegal during 1993. | during the 1993 rainy season, 15,806 mosquitoes, including 14,304 aedes ssp., were collected and tested for virus infection in 702 and 547 pools, respectively. aedes furcifer (edwards) was the most abundant species collected throughout the survey period. yellow fever (yf) virus was detected in 187 pools: ae. furcifer (123 isolates), ae. taylori (edwards) (41 isolates), and ae. luteocephalus (newstead) (23 isolates). a high prevalence of immunoglobulin (igg) antibodies was found in human and simi ... | 1996 | 8840681 |
| first evidence of natural vertical transmission of yellow fever virus in aedes aegypti, its epidemic vector. | entomological investigations were conducted in 1995 in senegal, following a yellow fever (yf) outbreak. a total of 1125 mosquitoes collected in the field, including males, females and 12-48 h old newly emerged adults reared from wild-caught larvae, were tested for yf virus. among the 22 species captured, aedes aegypti was the most common. 'wild' vectors of yf were also captured, including a. furcifer, a. metallicus and a. luteocephalus. in all, 28 yf virus isolations were made: 19 from a. aegypt ... | 1997 | 9463659 |
| anaphylaxis from yellow fever vaccine. | there are very few reports of anaphylactic reactions to yellow fever (yf) vaccine in the literature, and these date from the 1940s. | 1999 | 10200022 |
| recombinant, chimaeric live, attenuated vaccine (chimerivax) incorporating the envelope genes of japanese encephalitis (sa14-14-2) virus and the capsid and nonstructural genes of yellow fever (17d) virus is safe, immunogenic and protective in non-human primates. | yellow fever 17d virus, a safe and effective live, attenuated vaccine, was used as a vector for genes encoding the protective antigenic determinants of a heterologous member of the genus flavivirus, japanese encephalitis (je) virus, the leading cause of acute viral central nervous system infection and death throughout asia. the viral envelope (prm and e) genes of a full-length cdna clone of yf 17d virus were replaced with the corresponding genes of je sa14-14-2, a strain licensed as a live, atte ... | 1999 | 10217584 |
| [is there an alternative to the amaril 17d vaccine?]. | the live attenuated yellow fever vaccine 17d was found as early as 1936 by m. theiler of the rockfeller foundation. this strain of yellow fever is still the only one used today. the experience acquired with this vaccine has led to various changes in its composition: use of the seed lot system (in 1941) following the accidents observed in brazil; elimination of human plasma as stabilising agent because of hepatitis b transmission (1942); preparation of a vaccine free of avian leukemia; perfection ... | 1999 | 11000959 |
| yellow fever/japanese encephalitis chimeric viruses: construction and biological properties. | a system has been developed for generating chimeric yellow fever/japanese encephalitis (yf/je) viruses from cdna templates encoding the structural proteins prm and e of je virus within the backbone of a molecular clone of the yf17d strain. chimeric viruses incorporating the proteins of two je strains, sa14-14-2 (human vaccine strain) and je nakayama (je-n [virulent mouse brain-passaged strain]), were studied in cell culture and laboratory mice. the je envelope protein (e) retained antigenic and ... | 1999 | 10074160 |
| [yellow fever epidemiology in brazil]. | we have carried out a meticulous time-space-analysis of the incidence of yellow fever in humans in brazil from 1954 to 1972 and especially from 1973 to 1999. this study has added to our knowledge of the epidemiology of yellow fever and enabled us to redefine epidemiological zones and determine their geographical limits. the endemic area is located within the amazon basin; here cases are scattered and generally limited in number. however, there are also "foci of endemic emergence" within this are ... | 2001 | 11681224 |
| homogeneity of yellow fever virus strains isolated during an epidemic and a post-epidemic period in west africa. | three strains of yellow fever virus (yfv) were isolated in 1982 in the ivory coast, one from a human case and two from aedes luteocephalus, during and subsequent to an epidemic. the complete genomic sequence of the human strain was determined and compared to that of the 1927 asibi strain of yfv. the divergence observed was on average of 8.3%, ranging from 5.5 to 11.7% in the coding region. the transitions to transversions ratio was 5.9. most mutations (84.3%) occurred on the third position of th ... | 1997 | 9311567 |
| safety of biopharmaceuticals: a current perspective. | the impetus for this conference comes in large measure from the continuing development of the ich viral safety document concerned with testing and evaluation of the viral safety of biotechnology products derived from characterized cell lines of human or animal origin [1]. my opening remarks for this conference were, i think, suggested by the organizers in the belief that george santayana's quote, "those who cannot remember the past are condemned to repeat it" has validity for this effort. in thi ... | 1996 | 9119163 |
| isolation of yellow fever virus from man and mosquitoes in the amazon region of brazil. | | 1959 | 13661541 |
| demonstration of yellow fever virus in human cell culture by immunofluorescence. | | 1960 | 13720538 |
| stability of yellow fever vaccine. | yellow fever, an acute mosquito-borne viral haemorrhagic fever, is preventable by use of the live, attenuated 17d vaccine. the vaccine is used principally in tropical climates and is subject to potentially adverse conditions. lyophilized vaccine without stabilizers deteriorates rapidly when exposed to temperatures above -20 degrees c. in 1987, the who recommended that each lot of vaccine meet the following stability test: maintenance of potency (> 1,000 mouse i.c.ld50/human dose) with mean loss ... | 1996 | 8854020 |
| antibody-mediated infection of macrophages and macrophage-like cell lines with 17d-yellow fever virus. | the 17d vaccine strain of yellow fever virus (17d-yf) produces a safe human arboviral infection that can provide antisera of well-defined specificity under chronologically defined conditions. we studied 17d-yf growth in human peripheral blood macrophages and in two continuous fc receptor-bearing, macrophage-like cell lines, p388d1 of mouse origin and u937 of human origin. cells were infected with virus in the presence or absence of antibody to 17d-yf and to two related flaviviruses, st. louis en ... | 1981 | 7299376 |
| detection of yellow fever virus in serum by enzyme immunoassay. | yellow fever (yf) virus is present in patient's blood during the acute phase of illness. virus isolation and identification provide a potential method of early diagnosis, but available techniques are slow and require specialized materials and equipment. an alternative approach is direct detection of yf antigen in serum by means of an enzyme-linked immunosorbent assay (elisa). an antigen-capture elisa was developed, which used anti-yf antibodies, immobilized on a solid phase (polystyrene plates), ... | 1984 | 6364854 |
| a system of protein target sequences for anti-rna-viral chemotherapy by a vitamin b6-derived zinc-chelating trioxa-adamantane-triol. | the synthesis of the structurally unusual heterotricyclic compound 1-[3-hydroxy-5-(hydroxymethyl)-2-methyl-4-pyridinyl]-2,8,9-trioxaadamantane-3,5,7-triol (trivially named bananin, bn) from pyridoxylidenephloroglucinol and a theoretical prospect on possible biological activities of bn are presented in this report. pyridoxylidenephloroglucinol is synthesized by knoevenagel condensation of the vitamin b6 aldehyde pyridoxal with phloroglucinol. pyridoxylidenephloroglucinol rearranges to light-yello ... | 2003 | 14527557 |
| recent advancement in flavivirus vaccine development. | lately, the magnitude of cumulative diseases burden caused by flaviviruses, such as dengue virus, japanese encephalitis virus, tick-borne encephalitis virus, west nile virus and yellow fever virus, has reached an unprecedented level with the sizes of human and animal populations at risk increasing sharply. these diseases present highly complex medical, economic and ecologic problems, some effecting primarily human and others affecting human, livestock and wildlife. the large body of recent publi ... | 2004 | 15056045 |
| a single amino acid substitution in the envelope protein of chimeric yellow fever-dengue 1 vaccine virus reduces neurovirulence for suckling mice and viremia/viscerotropism for monkeys. | a chimeric yellow fever-dengue 1 (chimerivax-den1) virus was produced by the transfection of vero cells with chimeric in vitro rna transcripts. the cell culture supernatant was subjected to plaque purification for the identification of a vaccine candidate without mutations. of 10 plaque-purified clones, 1 containing no mutation (clone j) was selected for production of the vaccine virus. during subsequent cell culture passaging of this clone for vaccine production, a single amino acid substitutio ... | 2004 | 15331733 |
| effect of interval between inoculation of live smallpox and yellow-fever vaccines on antigenicity in man. | | 1972 | 4672744 |
| replication of chimeric yellow fever virus-dengue serotype 1-4 virus vaccine strains in dendritic and hepatic cells. | chimerivax-dengue (den) viruses are live attenuated vaccine candidates. they are constructed by replacing the premembrane (prm) and envelope (e) genes of the yellow fever (yf) 17d virus vaccine with the corresponding genes from wild-type den viruses (serotypes 1-4) isolated from humans. in this study, the growth kinetics of chimerivax-den1-4 and parent viruses (wild-type den-1-4 and yf 17d) were assessed in human myeloid dendritic cells (dcs) and in three hepatic cell lines (hepg2, huh7, and thl ... | 2005 | 15728870 |
| yellow fever vaccine: direct challenge of monkeys given graded doses of 17d vaccine. | in rhesus monkeys a wide dosage range of 17d yellow fever (yf) vaccine extending to a level even below that recommended for vaccination of man elicited an immune response providing solid protection to challenge with virulent yf virus. forty-three of 45 monkeys vaccinated with 10(2.3) or greater weanling mouse mean lethal doses of 17d vaccine were resistant to challenge 20 weeks later with virulent asibi strain yf virus. monkeys given graded doses of lesser amounts of vaccine were progressively m ... | 1973 | 4633476 |
| yellow fever vaccine. | yellow fever, a mosquito-borne viral hemorrhagic fever, is one of the most lethal diseases of humankind. the etiologic agent is the prototype member of the genus flavivirus, family flaviviridae, a group of small, enveloped, positive-sense, single-strand rna viruses. approximately one in seven people who become infected develop a rapidly progressive illness, with hepatitis, renal failure, hemorrhage and cardiovascular shock, with a case fatality rate of 20-50%. yellow fever occurs in sub-saharan ... | 2005 | 16117712 |
| broad-spectrum inhibitor of viruses in the flaviviridae family. | the viruses in the flaviviridae family have been associated with human and animal diseases. in this report, we demonstrate that compound 2-amino-8-(beta-d-ribofuranosyl) imidazo [1,2-a]-s-triazine-4-one (zx-2401) was capable of inhibiting the production in culture of at least five members of the flaviviridae family with minimal cytotoxicity. this compound inhibited yellow fever virus, dengue virus, bovine viral diarrhea virus, banzi virus and west nile virus with ec50 of 10, 10, 5, 5 and 3 micro ... | 2005 | 16199098 |
| live attenuated yellow fever 17d infects human dcs and allows for presentation of endogenous and recombinant t cell epitopes. | the yellow fever (yf) 17d vaccine is one of the most successful live attenuated vaccines available. a single immunization induces both long-lasting neutralizing antibody and yf-specific t cell responses. surprisingly, the mechanism for this robust immunity has not been addressed. in light of several recent reports suggesting flavivirus interaction with dendritic cells (dcs), we investigated the mechanism of yf17d interaction with dcs and the importance of this interaction in generating t cell im ... | 2005 | 16260489 |
| release of prostaglandin by mitogen- and antigen-stimulated leukocytes in culture. | the prostaglandin (pg) content of mitogen- and antigen-stimulated leukocyte cultures was examined by a radioimmunoassay procedure empolying an antiserum reactive with pgb(1) and pgb(2), the alkaline dehydration products of pge and pga. at 48 h, mitogen-activated mouse spleen cell cultures showed 2-10-fold increases in the pge, but not in the pga, component of immunoreactive pg (ipg) fractionated by silicic acid column chromatography. increases in ipg were detectable by h 16 in spleen cell cultur ... | 1974 | 4367890 |
| replication or inactivation of different viruses by human lymphocyte preparations. | cultures of phytohemagglutinin-stimulated, unstimulated, and frozen and thawed mononuclear (as controls) cells from normal human donors were infected with different viruses. a variable pattern of virus infectivity was noted, and influenza and coxsackie virus were rapidly inactivated even by stimulated lymphocytes. direct inactivation by lymphocytes may be one form of host defense in infection by some viruses. | 1974 | 4361296 |
| antiviral activity of cho-ss cell-derived human omega interferon and other human interferons against hcv rna replicons and related viruses. | the fully glycosylated human omega interferon produced from cho-ss cells (glycosylated ifn-omega) has been shown to be well-tolerated in man and to induce a sustained virologic response in patients infected with hepatitis c virus (hcv). we examined the antiviral activity of glycosylated ifn-omega and various human ifns (ifn-alpha, -beta, -gamma and non-glycosylated bacterial (escherichia coli) recombinant ifn-omega (non-glycosylated ifn-omega)) against hcv rna replicons and several viruses relat ... | 2007 | 16987555 |
| inhibition of hepatitis c replicon rna synthesis by beta-d-2'-deoxy-2'-fluoro-2'-c-methylcytidine: a specific inhibitor of hepatitis c virus replication. | beta-d-2'-deoxy-2'-fluoro-2'-c-methylcytidine (psi-6130) is a cytidine analogue with potent and selective anti-hepatitis c virus (hcv) activity in the subgenomic hcv replicon assay, 90% effective concentration (ec90)=4.6 +/- 2.0 microm. the spectrum of activity and cytotoxicity profile of psi-6130 was evaluated against a diverse panel of viruses and cell types, and against two additional hcv-1b replicons. the s282t mutation, which confers resistance to 2'-c-methyl adenosine and other 2'-methylat ... | 2006 | 17042329 |
| synthesis and in vitro evaluation of the anti-viral activity of n-[4-(1h(2h)-benzotriazol-1(2)-yl)phenyl]alkylcarboxamides. | a series n-[4-(1h(2h)-benzotriazol-1(2)-yl)phenyl]alkylcarboxamides (8e-k, 9e-i, k, l) and their parent amines (5a-c and 6a-d) were prepared according to schemes (1 and 2). compounds were evaluated in vitro for cytotoxicity and antiviral activity against a wide spectrum of rna (positive- and negative-sense) viruses, like [bovine viral diarrhea virus (bvdv), yellow fever virus (yfv), coxsackie virus b (cvb-2), polio virus (sb-1), human immunodeficiency virus (hiv-1), respiratory syncytial virus ( ... | 2006 | 17105439 |
| 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 ... | 1986 | 3700596 |
| mouse and hamster models for the study of therapy against flavivirus infections. | small animal models that are reminiscent of flaviviral disease in human will be instrumental in identifying therapeutic strategies against flavivirus infections. here we review models in mice and hamsters for the most clinically important flaviviruses: dengue virus, yellow fever virus, west nile virus, japanese encephalitis virus and tick-borne encephalitis virus. in addition, models are discussed that employ no known vector viruses such as the modoc virus. these viruses can be manipulated in bs ... | 2006 | 17319165 |
| distinct gene expression profiles in peripheral blood mononuclear cells from patients infected with vaccinia virus, yellow fever 17d virus, or upper respiratory infections. | gene expression in human peripheral blood mononuclear cells was systematically evaluated following smallpox and yellow fever vaccination, and naturally occurring upper respiratory infection (uri). all three infections were characterized by the induction of many interferon stimulated genes, as well as enhanced expression of genes involved in proteolysis and antigen presentation. vaccinia infection was also characterized by a distinct expression signature composed of up-regulation of monocyte resp ... | 2007 | 17651872 |
| identification of novel small-molecule inhibitors of west nile virus infection. | west nile virus (wnv) has spread throughout the united states and canada and now annually causes a clinical spectrum of human disease ranging from a self-limiting acute febrile illness to acute flaccid paralysis and lethal encephalitis. no therapy or vaccine is currently approved for use in humans. using high-throughput screening assays that included a luciferase expressing wnv subgenomic replicon and an ns1 capture enzyme-linked immunosorbent assay, we evaluated a chemical library of over 80,00 ... | 2007 | 17715228 |
| nucleic acid-based inhibition of flavivirus infections. | the genus flavivirus in the family flaviviridae consists of many arthropod-transmitted human pathogens, including dengue, yellow fever, japanese encephalitis, west nile, st. louis encephalitis, murray valley encephalitis, and tick-borne encephalitis viruses. treatment options against flaviviral disease are extremely limited, with no effective drugs yet commercially available. recent advances in virology, synthetic organic chemistry, and the discovery of rna interference (rnai), have provided the ... | 2008 | 17981637 |
| 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 ... | 1988 | 3152785 |
| murray valley encephalitis virus field strains from australia and papua new guinea: studies on the sequence of the major envelope protein gene and virulence for mice. | we have compared the nucleotide sequence of the gene encoding the major envelope (e) protein of a number of murray valley encephalitis virus (mve) isolates from australia and papua new guinea (png). the isolates, from widely separated geographic regions, were from four fatal human cases, a heron, and six mosquito pools and covered a period of 25 years. the sequences of the australian strains were notable for their similarity, showing not more than 1.7% nucleotide sequence divergence in pairwise ... | 1988 | 2838962 |
| development of a human-murine chimeric immunoglobulin m antibody for use in the serological detection of human flavivirus antibodies. | current diagnosis of human flaviviral infections relies heavily on serological techniques such as the immunoglobulin m (igm) antibody capture enzyme-linked immunosorbent assay (mac-elisa). broad application of this assay is hindered by a lack of standardized human positive-control sera that react with the wide variety of flaviviruses that can cause human disease, e.g., dengue virus (denv), west nile virus (wnv), yellow fever virus (yfv), japanese encephalitis virus (jev), and st. louis encephali ... | 2009 | 19297614 |
| viral diseases involving the liver. | even though hav, hbv and hnanb viruses are responsible for most of the viral hepatitis cases, many other viruses have been reported to cause hepatic injury. these viruses may involve the liver, either as part of a systemic illness (e.g. ebv, cmv, hsv) or as the primary target organ (e.g. yellow fever virus, lassa fever virus, ebola virus). clinically overt hepatocellular dysfunction is rare in such viral infections. biochemical disturbance of hepatic functions shown, for example, by rises in ast ... | 1987 | 2822180 |
| synthesis of 3-deazaneplanocin a, a powerful inhibitor of s-adenosylhomocysteine hydrolase with potent and selective in vitro and in vivo antiviral activities. | the neplanocin a analogue 3-deazaneplanocin a (2b) has been synthesized. a direct sn2 displacement on the cyclopentenyl mesylate 3 by the sodium salt of 6-chloro-3-deazapurine afforded the desired regioisomer 4 as the major product. after deprotection, this material was converted to 3-deazaneplanocin a in two steps. x-ray crystallographic analysis confirmed the assigned structure. consistent with its potent inhibition of s-adenosylhomocysteine hydrolase, 3-deazaneplanocin a displayed excellent a ... | 1989 | 2544721 |
| chromosomal aberrations in germ cells of male mice immunised with attenuated viral vaccines (human). | the cytogenetic effects of two attenuated viral vaccines (yellow fever vaccine and oral poliomyelitis vaccine) were assessed by means of the analysis of meiotic spermatocyte chromosomes in mice. in a dose of 0.5 ml, but not 0.1 ml, both vaccines induced a significant percentage of chromosomal aberrations after 7, 14 and 30 days. euploidy was the major abnormality produced by yellow fever vaccine. the various abnormalities produced by oral polio vaccine were significant when pooled, but not when ... | 1990 | 2304066 |
| [the epidemiology of yellow fever in western africa]. | observations made during the epidemics in côte d'ivoire (1982), burkina faso (1983), nigeria (1986 and 1987) and mali (1987), together with studies conducted in the last 10 years, particularly in côte d'ivoire, now make it possible, without calling into question the dynamics of yellow fever virus circulation in space and time, to redefine some features of the pattern suggested in 1977 and refined on a number of occasions up to 1983. the endemicity area is still the region of epizootic and enzoot ... | 1991 | 2054923 |
| seasonal abundance and diel landing periodicity of sabethes chloropterus (diptera: culicidae) in trinidad, west indies. | the seasonal occurrence and diel landing periodicity of sabethes chloropterus (humboldt) was studied weekly for 1 yr using the human bait catch in the pt. gourde forest, trinidad, w.i. population abundance remained low throughout the dry season (16%) but increased after the onset of the rains in may and peaked by the middle of the rainy season (july-october). the diurnal periodicity of landing was unimodal during the wet season with a major peak between 1200-1600 hours and bimodal during the dry ... | 1990 | 1980705 |
| sylvatic yellow fever activity in trinidad, 1988-1989. | of a total of 18,068 mosquitoes (361 pools) collected in south-eastern trinidad forests from december 1988 to may 1989, 47 species belonging to 14 genera were identified. five yellow fever virus isolates were made from haemagogus janthinomys and one from sabethes chloropterus. all the other pools of mosquitoes examined were negative for the virus. the mosquito isolates were made in december and january. in addition, in late february and early march, 2 infected howler monkeys (alouatta sp.) were ... | 1990 | 1971734 |
| heterogeneity in envelope protein sequence and n-linked glycosylation among yellow fever virus vaccine strains. | we have compared the deduced envelope (e) protein sequences of two biologically well-characterized yellow fever (yf) virus vaccine strains. the 17dd strain has been produced in brazil for more than 50 years and used to successfully vaccinate millions of people worldwide. the 17d-213 is a candidate vaccine strain produced in tissue culture which has previously passed the monkey neurovirulence assay for testing human yf vaccines. nucleotide sequence analysis of polymerase chain reaction-amplified ... | 1992 | 1566570 |
| use of mac-elisa for evaluation of yellow fever vaccination. | an evaluation of the igm antibody immune response against yellow fever using strain 17d was carried out by mac-elisa and prnt. the results showed an agreement of 97% between both tests and the authors conclude that mac-elisa can be used as a specific and sensitive assay to replace the prnt for detecting yellow fever antibodies in human sera, after vaccination programs. | 1992 | 1342109 |
| recent laboratory contributions to the control of yellow fever: (section of tropical diseases and parasitology). | the most important recent laboratory contributions to the control of yellow fever will be briefly summarized under three headings: (1) methods of diagnosis, (2) transmission, and (3) protection.(1) methods of diagnosis.-the development of improved methods of identification, in particular by immunity tests, has made it possible to diagnose yellow fever with much greater certainty. moreover, since the immunity following an attack of the disease is usually of life-long duration, it is possible to d ... | 1933 | 19989606 |
| yellow fever virus transmission via breastfeeding: follow-up to the paper on breastfeeding travelers. | | 2010 | 20636609 |
| molecular epidemiology of yellow fever in bolivia from 1999 to 2008. | yellow fever (yf) is a serious public health problem in bolivia since at least the 19th century. surprisingly, very limited information has been made available to date regarding the genetic characterisation and epidemiology of bolivian yf virus (yfv) strains. here, we conducted the genetic characterization of 12 human isolates of yfv collected in bolivia between 1999 and 2008, by sequencing and analysis of two regions of the viral genome: a fragment encoding structural proteins "prm" (premembran ... | 2010 | 20925524 |
| antiviral activities of isg20 in positive-strand rna virus infections. | isg20 is an interferon-inducible 3'-5' exonuclease that inhibits replication of several human and animal rna viruses. however, the specificities of isg20's antiviral action remain poorly defined. here we determine the impact of ectopic expression of isg20 on replication of several positive-strand rna viruses from distinct viral families. isg20 inhibited infections by cell culture-derived hepatitis c virus (hcv) and a pestivirus, bovine viral diarrhea virus and a picornavirus, hepatitis a virus. ... | 2010 | 21036379 |
| human antibodies to dengue and yellow fever do not react in diagnostic assays for hepatitis c virus. | hepatitis c virus (hcv) is a recently described causative agent of the great majority of post-transfusion non a-non b hepatitis and is classified within the flaviviridae family. due to a high prevalence of anti-hcv and other flaviviruses circulating in brazil, such as dengue and yellow fever, we investigated the possibility of serological cross-reactivity between these viruses. different panels of human sera positive for dengue type 1 (9 cases) and type 2 (7 cases) from 6 patients naturally infe ... | 1992 | 1285268 |
| [entomological investigations conducted around ten cases of yellow fever in 2009 in the denguélé sanitary region, côte-d'ivoire.] | in november 2009, ten suspicious cases of yellow fever, including six deaths, were notified in the region of denguélé, in the northwest of côte-d'ivoire. in order to evaluate the extent of yellow fever virus circulation and the risk for local people, a mission of entomological investigation was carried out by the ministry of health and public hygiene of côte-d'ivoire. entomological investigations were conducted in the villages of confirmed cases (banakoro and tron-touba) and the centers of consu ... | 2011 | 21293956 |
| 2,3-dihydro-1,2-diphenyl-substituted 4h-pyridinone derivatives as new anti flaviviridae inhibitors. | with the aim of identifying novel lead compounds active against emergent human infectious diseases, a series of 2,3-dihydro-4h-pyridinone derivatives has been prepared and evaluated for antiviral activity. compounds were evaluated in vitro in cell-based assays for cytotoxicity and against a wide spectrum of viruses. in the antiviral screening, several compounds showed to be fairly active against viruses belonging to the flaviviridae family. the pestiviruses (bovine viral diarrhoea virus) were in ... | 2011 | 21414145 |
| a diverse range of gene products are effectors of the type i interferon antiviral response. | the type i interferon response protects cells against invading viral pathogens. the cellular factors that mediate this defence are the products of interferon-stimulated genes (isgs). although hundreds of isgs have been identified since their discovery more than 25 years ago, only a few have been characterized with respect to antiviral activity. for most isg products, little is known about their antiviral potential, their target specificity and their mechanisms of action. using an overexpression ... | 2011 | 21478870 |
| yellow fever virus envelope protein expressed in insect cells is capable of syncytium formation in lepidopteran cells and could be used for immunodetection of yfv in human sera. | abstract: background: yellow fever is an haemorrhagic disease caused by a virus that belongs to the genus flavivirus (flaviviridae family) and is transmitted by mosquitoes. among the viral proteins, the envelope protein (e) is the most studied one, due to its high antigenic potencial. baculovirus are one of the most popular and efficient eukaryotic expression system. in this study a recombinant baculovirus (vsynyfe) containing the envelope gene (env) of the 17d vaccine strain of yellow fever vir ... | 2011 | 21619598 |
| 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. ... | 1977 | 407675 |
| epidemic of jungle yellow fever in brazil, 2000: implications of climatic alterations in disease spread. | seventy-seven human cases of sylvatic yellow fever were reported in brazil during the period january-june 2000. the first cases were reported 1 week after new year's day and originated at chapada dos veadeiros, a tourist canyon site in goiás state, near brasília, the brazilian capital. the laboratory procedures used for diagnoses included serology with an igm capture assay and plaque reduction neutralization test, virus isolation in suckling mice and c6/36 cells, and immunohistochemistry. all ca ... | 2001 | 11596099 |
| yellow fever vaccination of human immunodeficiency virus-infected patients: report of 2 cases. | yellow fever vaccine (17d, a live attenuated virus vaccine) was effective and safe in 2 human immunodeficiency virus-infected patients without severe immunosuppression, one of whom traveled to kenya and the other of whom traveled to senegal. | 2000 | 11017859 |
| flavivirus ns3 and ns5 proteins interaction network: a high-throughput yeast two-hybrid screen. | the genus flavivirus encompasses more than 50 distinct species of arthropod-borne viruses, including several major human pathogens, such as west nile virus, yellow fever virus, japanese encephalitis virus and the four serotypes of dengue viruses (denv type 1-4). each year, flaviviruses cause more than 100 million infections worldwide, some of which lead to life-threatening conditions such as encephalitis or haemorrhagic fever. among the viral proteins, ns3 and ns5 proteins constitute the major e ... | 2011 | 22014111 |
| infection of scid mice with montana myotis leukoencephalitis virus as a model for flavivirus encephalitis. | we have established a convenient animal model for flavivirus encephalitis using montana myotis leukoencephalitis virus (mmlv), a bat flavivirus. this virus has the same genomic organization, and contains the same conserved motifs in genes that encode potential antiviral targets, as flaviviruses that cause disease in man (n. charlier et al., accompanying paper), and has a similar particle size (approximately 40 nm). mmlv replicates well in vero cells and appears to be equally as sensitive as yell ... | 2002 | 12124452 |
| host and viral traits predict zoonotic spillover from mammals. | the majority of human emerging infectious diseases are zoonotic, with viruses that originate in wild mammals of particular concern (for example, hiv, ebola and sars). understanding patterns of viral diversity in wildlife and determinants of successful cross-species transmission, or spillover, are therefore key goals for pandemic surveillance programs. however, few analytical tools exist to identify which host species are likely to harbour the next human virus, or which viruses can cross species ... | 2017 | 28636590 |
| vaccines for viral diseases with dermatologic manifestations. | vaccines against infectious diseases have been available since the 1800s, when an immunization strategy against smallpox developed by jenner gained wide acceptance. until recently, the only vaccination strategies available involved the use of protein-based, whole killed, and attenuated live virus vaccines. these strategies have led to the development of effective vaccines against a variety of diseases with primary or prominent cutaneous manifestations. effective and safe vaccines now used worldw ... | 2003 | 12757257 |
| the resistance of a2g mice to myxoviruses. | | 1963 | 14050204 |
| effects of cortisone on in vitro viral infection. i. inhibition of cytopathogenesis by polio, rabies and yellow fever viruses in human embryonic cells. | | 1965 | 14297833 |
| a regional reconnaissance on yellow fever in the sudan; with special reference to primate hosts. | neutralization-tests with yellow fever virus performed on 666 human sera collected in the southern sudan imply that yellow fever is still endemic south of the 10th parallel, in the south-west border of the nuba mountains, and in the plains west of the nuba mountains as far north as el muglad. similar tests on bloods from 110 primates revealed a high rate of immunity among both baboons (papio sp.) (94%) and grivet monkeys (cercopithecus aethiops) (77%), and a very low rate (1 in 56) among galagos ... | 1955 | 14379007 |
| [yellow fever--a tropical danger]. | yellow fever is an acute life-threatening viral infection. in the case of the urban type, the virus is transmitted from one human to another by the aedes mosquito vector. in particular travelers to africa from non-endemic areas run a high risk of clinical disease in case of infection. for prophylaxis, a reliable live virus vaccine is available. | 2004 | 15529706 |
| phenotypic and molecular characterization of a non-lethal, hamster-viscerotropic strain of yellow fever virus. | viscerotropic yellow fever virus (yfv) infection occurs primarily in humans and non-human primates. lack of an appropriate small animal model of viscerotropic yfv infection has been a major deterrent to molecular studies of viscerotropism. a hamster model of viscerotropic yfv infection has recently been described; however, these studies have focused on hamster-viscerotropic strains of yfv (including asibi hamster p7 virus) that caused outward clinical signs of infection and mortality. in order t ... | 2005 | 15845256 |
| revisiting the liver in human yellow fever: virus-induced apoptosis in hepatocytes associated with tgf-beta, tnf-alpha and nk cells activity. | flavivirus infection as dengue and yellow fever persists as a terrible menace to pandemics, due to aedes prevalence in the americas. yellow fever is characterized by hepatocyte damage, with steatosis, apoptosis and necrosis, mainly in the midzonal region of the liver, but the injury mechanism has not been studied at the light of recent knowledge, such as the advances in cell death mechanisms, inflammatory response and cytokine cell expression tools. we studied 53 human liver paraffin embedded bl ... | 2006 | 16278000 |
| virological and serological studies of a suspected yellow fever virus outbreak in mabudi area of benue plateau state of nigeria. | human sera collected during a suspected yellow fever outbreak in mabudi, benue-plateau state of nigeria were examined for virus content by mouse inoculation, and presence of antibody by complement fixation (cf) and neutralization (n) tests in baby mice. no virus was isolated from 116 sera examined. 40 and 41 of the 358 sera tested were positive for yellow fever and ugmp 359 cf antibodies respectively, with 12 possession cf antibodies to both viruses. in neutralization tests, 91 and 99 of the 243 ... | 1976 | 16296128 |
| restricted replication and lysosomal trafficking of yellow fever 17d vaccine virus in human dendritic cells. | the yellow fever virus attenuated 17d vaccine strain is a safe and effective vaccine and a valuable model system for evaluating immune responses against attenuated viral variants. this study compared the in vitro interactions of the commercially available yellow fever vaccine (yf-vax), dengue virus and the live-attenuated dengue vaccine pdk50 with dendritic cells (dcs), the main antigen-presenting cells at the initiation of immune responses. similar to pdk50, infection with yf-vax generated acti ... | 2007 | 17170447 |
| human effector and memory cd8+ t cell responses to smallpox and yellow fever vaccines. | to explore the human t cell response to acute viral infection, we performed a longitudinal analysis of cd8(+) t cells responding to the live yellow fever virus and smallpox vaccines--two highly successful human vaccines. our results show that both vaccines generated a brisk primary effector cd8(+) t cell response of substantial magnitude that could be readily quantitated with a simple set of four phenotypic markers. secondly, the vaccine-induced t cell response was highly specific with minimal b ... | 2008 | 18468462 |
| the immunostimulatory power of acute viral infection. | in this issue of immunity, miller et al. (2008) use multiple independent techniques to demonstrate that antiviral t cell responses after acute human infection are much larger than previously realized. | 2008 | 18482565 |
| longitudinal myelitis associated with yellow fever vaccination. | severe adverse reaction to yellow fever (yf) vaccine includes the yellow fever vaccine-associated neurotropic disease. this terminology includes postvaccinal encephalitis, acute disseminated encephalomyelitis, and guillain-barré syndrome. the objective of this communication is to report a patient who received a yf vaccine in argentina and subsequently developed longitudinal myelitis with a symptom that had previously gone unreported in the literature. a 56-year-old man began with progressive par ... | 2009 | 19579072 |
| early triggering of exclusive ifn-gamma responses of human vgamma9vdelta2 t cells by tlr-activated myeloid and plasmacytoid dendritic cells. | gammadelta t cells, a major innate-like t cell subset, are thought to play in vivo an important role in innate and adaptive immune responses to various infection agents like parasites, bacteria, or viruses but the mechanisms contributing to this immune process remain ill defined. owing to their ability to recognize a broad set of microbial molecular patterns, tlrs represent a major innate pathway through which pathogens induce dendritic cells (dc) maturation and acquisition of immunostimulatory ... | 2009 | 19710464 |
| in vitro evaluation of the antiviral activity of extracts from the lichen parmelia perlata (l.) ach. against three rna viruses. | substances extracted from lichens have previously been reported to possess antimicrobial activities against various groups of bacteria, fungi and viruses. due to the high abundance of parmelia perlata in the eastern parts of nigeria, we decided to explore whether it possesses antiviral activity against some common animal and human viruses. | 2007 | 19734611 |
| a mouse model for studying viscerotropic disease caused by yellow fever virus infection. | mosquito-borne yellow fever virus (yfv) causes highly lethal, viscerotropic disease in humans and non-human primates. despite the availability of efficacious live-attenuated vaccine strains, 17d-204 and 17dd, derived by serial passage of pathogenic yfv strain asibi, yfv continues to pose a significant threat to human health. neither the disease caused by wild-type yfv, nor the molecular determinants of vaccine attenuation and immunogenicity, have been well characterized, in large part due to the ... | 2009 | 19816561 |
| infectivity of blood during the course of experimental yellow fever. | five m. rhesus fatally infected with yellow fever virus ran varied and typical courses, death occurring from 82 hours to 10 days after infecting. batches of a. aegypti were fed daily on each monkey and specimens of blood injected into other animals. by mosquito transfer, the virus was found to be circulating in the peripheral blood 1 or 2 days after the infecting and the same interval before the onset of fever; in one instance, mosquitoes became infectious by feeding on a monkey 12 hours after i ... | 1929 | 19869649 |
| 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 ... | 1930 | 19869721 |
| vaccination against yellow fever with immune serum and virus fixed for mice. | 1. after preliminary experiments in monkeys, 15 persons were actively immunized by a single injection of a dried mixture of living yellow fever virus, fixed for mice, and human immune serum, with separate injections of enough additional serum to make up the amount required for protection. 2. one person was similarly immunized by injecting immune serum and dried virus separately. 3. by titration of the sera of vaccinated persons in mice, it was shown that the immunity rose in a few weeks to a hei ... | 1932 | 19870044 |
| 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 ... | 1937 | 19870634 |
| differential cytokine responses from primary human kupffer cells following infection with wild-type or vaccine strain yellow fever virus. | wild-type yellow fever virus (yfv) infections result in a hepatotropic disease which is often fatal, while vaccination with the live-attenuated 17-d strain results in productive infection yet is well-tolerated with few adverse events. kupffer cells (kcs) are resident liver macrophages that have a significant role in pathogen detection, clearance and immune signaling. although kcs appear to be an important component of yf disease, their role has been under-studied. this study examined cytokine re ... | 2011 | 21277609 |
| Monoclonal antibodies against dengue NS2B and NS3 proteins for the study of protein interactions in the flaviviral replication complex. | The replication of dengue virus (DENV) RNA requires at least two viral non-structural (NS) proteins, NS3 and NS5. To facilitate the study of the DENV replication complex, human monoclonal IgG that are specific for NS proteins have been generated and characterised. The anti-NS3 IgG, 3F8, binds a conserved epitope (aa526-531) in the NS3 helicase domain, and cross-reacts with NS3 from all four DENV serotypes and the related yellow fever virus. The anti-NS2B IgG, 3F10, binds aa49-66 of NS2B (CF18), ... | 2012 | 22040846 |
| no evidence of murine leukemia virus-related viruses in live attenuated human vaccines. | the association of xenotropic murine leukemia virus (mlv)-related virus (xmrv) in prostate cancer and chronic fatigue syndrome reported in previous studies remains controversial as these results have been questioned by recent data. nonetheless, concerns have been raised regarding contamination of human vaccines as a possible source of introduction of xmrv and mlv into human populations. to address this possibility, we tested eight live attenuated human vaccines using generic pcr for xmrv and mlv ... | 2011 | 22216219 |
| dengue virus seroprevalence among febrile patients in bamako, mali: results of a 2006 surveillance study. | abstract background: dengue viruses (denv) are endemic in over 100 countries worldwide, and annually 50 to 100 million people are infected by one of the four denv serotypes, whereas over 2.5 billion people are at risk for infection. west african countries lack the surveillance to determine the true incidence of dengue; hence, this disease is likely significantly underestimated. in mali, ~14 million people are potentially at risk of acquiring a dengue infection. methods and findings: a serosurvey ... | 2011 | 21767159 |
| from research to phase iii: preclinical, industrial and clinical development of the sanofi pasteur tetravalent dengue vaccine. | dengue vaccine development has reached a major milestone with the initiation, in 2010, of the first phase iii clinical trial to investigate the sanofi pasteur cyd tetravalent dengue vaccine (tdv). the cyd tdv candidate is composed of four recombinant, live, attenuated vaccines (cyd-1-4) based on a yellow fever vaccine 17d (yfv 17d) backbone, each expressing the pre-membrane and envelope genes of one of the four dengue virus serotypes. the vaccine is genetically and phenotypically stable, non-hep ... | 2011 | 21745521 |