Publications

a seroepidemiological study for rift valley fever virus in humans and domestic animals in egypt.		1978	752699
ecological and epidemiological studies of rift valley fever in egypt.		1978	752700
seriologic and vector comparisons of rift valley virus with other bunyaviruses.		1978	752702
propagation of rvf virus in goat kidney cell culture.		1978	752703
serologic response of man to inactivated rift valley fever vaccine.		1978	752704
preliminary studies on goat kidney cell culture as a possible substrate for veterinary rvf vaccine.		1978	752705
epidemic of rift valley fever (rvf) in egypt: isolation of rvf virus from animals.		1978	752707
studies on goats experimentally infected with r.v.f. virus.		1978	752709
the use of cattle to protect sheep from bluetongue infection.	studies on the host preferences of culicoides imicola, the vector of bluetongue virus in south africa, are reviewed. there is agreement that this species prefers to feed on cattle but will also feed on other bovidae and sheep. over a seven year period cattle kept near sheep on a natal farm appear to have appreciably reduced the incidence of bluetongue in the sheep. in addition to immunization this "decoy" approach is therefore recommended to assist in the protection of stock from insect borne di ...	1978	215768
preparation and use of a stable, inactivated rift valley fever antigen.		1978	24056
viral haemorrhagic fevers of man.	this article reviews the current state of knowledge on the viral haemorrhagic fevers that infect man, namely smallpox, chikungunya fever, dengue fever, rift valley fever, yellow fever, crimean haemorrhagic fever, kyasanur forest disease, omsk haemorrhagic fever, argentinian haemorrhagic fever (junin virus), bolivian haemorrhagic fever (machupo virus), lassa fever, haemorrhagic fever with renal syndrome, and marburg and ebola virus diseases.	1978	310725
rift valley fever: the role of the vervet monkey as a reservoir or maintenance host for this virus.		1978	418540
rift valley fever encephalitis. a description of a case.		1979	421266
rift valley fever virus: some ultrastructural observations on material from the outbreak in egypt 1977.	rift valley fever virus isolates from the 1977 outbreak in egypt were studied at an ultrastructural level. the particles measured 90 to 110 nm in diam. using negative staining and sectioning techniques, with a core component of 80 to 85 nm. the surface of the virions was calculated to be covered by approx. 160 sub-units. the particles were found in smooth endoplasmic reticular systems, which were made up of either multi-tubular complexes, or of a single large vacuole. the majority of these membr ...	1979	422955
[rift valley fever, a veterinary and medical problem (author's transl)].	rift valley fever probably occurred in east and south africa for many years, where it occasionally caused sever epizootics among sheep and to a less extent in cattle and goats. particularly newborn animals fall victims to the disease, whereas the majority of pregnant ewes and cows abort. in recent years, the disease spread to the sudan and reached the nile delta in 1977, where it not only caused an epizootic but also an epidemic among the population, resulting in approximately 18,000 cases and n ...	1979	494210
an epizootic of rift valley fever in egypt in 1977.	a disease causing increased mortality and abortion in domestic animals during a 1977 epizootic in egypt was identified as rift valley fever (rvf) virus. the epizootic included extensive human involvement reflected clinically as either an acute febrile, ocular, encephalitic, or fatal haemorrhagic form of rvf disease. the virus was again isolated from humans and animals during a second rvf epizootic in the summer of 1978.	1979	505918
pathogenicity of different strains of rift valley fever virus in swiss albino mice.	laboratory mice were inoculated with 3 different strains of rift valley fever virus (rvfv): namely, the prototype, the nigerian, and the lunyo variant strains of rvfv. animals were inoculated with either infective mouse brain or serum by the i.c. or i.p. route and organs of inoculated animals examined for virus content and histopathological changes. animals inoculated with either the classical or the nigerian encephalitis only, to a ditropism involving mild lesions in the brain and liver or the ...	1979	508592
rift valley fever. a survey for antibody to the virus in bird species commonly found in situations considered to be enzootic.		1979	531912
the rift valley fever epizootic in egypt 1977-78. 1. description of the epizzotic and virological studies.	from october to december 1977, an extensive epizootic occurred in egypt resulting in abortions and increased mortality in domestic animals, and severe clinical disease with fatalities in man. rift valley fever (rvf) virus was isolated and identified as the causative agent. in humans, acute febrile, encephalitic, ocular and fatal haemorrhagic diseases were documented as resulting from rvf virus infection. a retrospective serological survey indicated rvf was recently introduced into the area. the ...	1979	538803
susceptibility of cer cell line to rift valley fever virus.		1979	541587
rift valley fever vaccine--antibody and immune response in cattle to a live and an inactivated vaccine.	in a study of the response in cattle to a live and an inactivated rift valley fever (rvf) vaccine prepared from cell cultures infected with rvf virus, the effects of varying doses and combinations of these vaccines were compared. the antibody response to a primary injection of either vaccines was poor when measured by the serum virus neutralization test (svn) and the haemagglutination-inhibition test (hi) but a booster dose of inactivated vaccine evoked a good anamnestic response in cattle previ ...	1979	551199
an epidemic of rift valley fever in egypt. 1. diagnosis of rift valley fever in man.	rift valley fever (rvf) virus was isolated from 53 of 56 sera collected from patients with a clinical picture of dengue-like illness during the peak of the epidemic of rvf in egypt in the autumn of 1977. rvf virus was also isolated from the throat washings of two patients and the faeces of four, all of whom were positive for virus isolation from the serum. all the isolates were identified by the complement fixation (cf) test. serological diagnosis of rvf, using paired sera from 16 patients, was ...	1979	314354
an epidemic of rift valley fever in egypt. 2. isolation of the virus from animals.	during the epidemic of rift valley fever (rvf) that occurred in egypt and other areas of north africa in 1977, the virus was isolated from various species of domestic animal and rats (rattus rattus frugivorus) as well as man. the highest number of rvf virus isolates were obtained from sheep; only one isolate was recovered from each of the other species tested, viz. cow, camel, goat, horse, and rat. rvf virus was reisolated from both camel and horse sera, apparently for the first time.	1979	314355
the rift valley fever epizootic in egypt 1977-78. 2. ecological and entomological studies.	epidemiological factors related to the introduction, spread and maintenance of rift valley fever (rvf) virus were studied during the 1977-78 epizootic in egypt, culex pipiens is the most ubiquitous and prevalent mosquito species in the nile valley and delta. isolation of rvf virus from unengorged c. pipiens, and demonstration of laboratory transmission of the virus by this species, strongly implicate it as the chief vector in egypt. virus transmission to man also occurs by contamination when han ...	1979	44038
spread of rift valley fever virus from continental africa.		1979	91909
clinical, virological and serological response of the west african dwarf sheep to experimental infection with different strains of rift valley fever virus.	west african dwarf sheep were inoculated with three different strains of rift valley fever virus (rvfv). using infective mouse serum as the source of virus classical rvfv disease characterised by sudden onset, a sharp but transient febrile response, viraemia, abortions and the development of specific rvfv antibodies in surviving animals was observed. the severity of clinical response was, however, dependent on the strain of virus used, with animals inoculated with smithburn's neuroadapted strain ...	1979	262596
immunological reactions of rift valley fever virus strains from east and west africa.	three strains of rift valley fever virus, namely nigerian (nig), smithburn's neurotropic (snt), and lunyo variant (lun) were compared by complement fixation (cf), neutralisation (n), haemagglutination/haemagglutination-inhibition (ha/hi) and agar gel diffusion (agd) tests. they showed reciprocal cross-reactivity in cf tests. in n tests, using immune sheep sera, there was reciprocal cross-neutralisation between the nig and snt strains, but not with the lun strain, the antiserum of which neutralis ...	1979	262597
immune response of steers, goats and sheep to inactivated rift valley fever vaccine.		1979	298921
hemorrhagic fevers, with special reference to recent outbreaks in southern africa.	in considering the diagnosis of a patient admitted to the johannesburg hospital, suffering from an illness characterized by high fever and complicated by a hemorrhagic state from which he died, a list of possible causes of his illness was drawn up. this list included the arthropodborne viral infections prevalent in southern africa, namely, chikungunya fever, sindbis fever, west nile fever, yellow fever, and rift valley fever; viral infections associated with rodents, such as lassa fever; the vir ...	1979	399369
antibodies to rift valley fever virus in swedish u.n. soldiers in egypt and the sinai.	swedish united nations emergency forces soldiers serving in egypt and the sinai peninsula were serologically tested for hemagglutination-inhibiting antibodies to rift valley fever (rvf) virus. eight of 170 were positive. rvf has not been reported outside africa, and a survey of 500 swedish soldiers who had not served in the middle east or africa revealed no rvf virus antibodies. there were extensive rvf epidemics in egypt in 1977 and 1978, and it is considered that these serologically positive s ...	1979	575230
serological relation between rift valley fever virus and viruses of phlebotomus fever serogroup.		1980	6103252
vector studies on rift valley fever virus in south africa.		1980	6105722
weather, host and vector--their interplay in the spread of insect-borne animal virus diseases.	the spread of insect-borne animal virus diseases is influenced by a number of factors. hosts migrate, move or are conveyed over long distances: vectors are carried on the wind for varying distances in search of hosts and breeding sites; weather and climate affect hosts and vectors through temperature, moisture and wind. as parasites of host and vector, viruses are carried by animals, birds and insects, and their spread can be correlated with the migration of hosts and the carriage of vectors on ...	1980	6131919
[brain teratology as a result of transplacental virus infection in ruminants].	various viruses relating to congenital brain teratology in ruminants are discussed. these include: bluetongue which may be responsible for porencephaly and hydranencephaly; akabane disease, rift valley fever (mouse brain attenuated virus) and wesselsbron disease (wild-type and mouse brain attenuated viruses) which can give rise to porencephaly, hydranencephaly, micrencephaly and cerebellar hypoplasia, and bovine viral diarrhoea-mucosal disease which results only in cerebellar hypoplasia. certain ...	1980	6267276
the extended horizons of rift valley fever: current and projected immunogens.		1980	7208510
evaluation of a formalin-inactivated rift valley fever vaccine in sheep.	a formalin-inactivated rift valley fever (rvf) vaccine prepared in cell culture for human use was immunogenic in sheep. vaccine was administered as a single dose of diluted (1:5) or undiluted vaccine with or without an adjuvant. serum-neutralizing antibodies induced by rvf vaccine persisted for at least 7 months. seven of 11 vaccinated sheep with prechallenge plaque-reduction neutralization (prn80) antibody titers of less than or equal to 10 were protected against challenge exposure with 10(6) p ...	1980	7224281
biochemical characterization of rift valley fever virus.		1980	7414952
glucan-induced enhancement of host resistance to selected infectious diseases.	we conducted studies with mice, rats, and monkeys which demonstrated the ability of glucan to induce either nonspecific or specific enhancement of host resistance to infectious diseases. intravenous pretreatment of mice with glucan significantly enhanced the survival of mice challenged with either venezuelan equine encephalomyelitis (vee) virus or rift valley fever virus. pretreatment was beneficial when initiated 3 days before challenge with vee virus and 7 days before challenge with rift valle ...	1980	7439978
possible vectors of rift valley fever in kenya.		1980	6111141
[an ominous zoonosis: rift valley fever].		1980	7455276
rift valley fever in humans in south africa.	during an epizootic of rift valley fever in south africa in 1974/1975, mainly affecting sheep and cattle, a large number of human cases occurred. the majority of the patients, mostly farmers, farm labourers and veterinary surgeons, acquired the infection while handling the carcasses of animals which had died of rift valley fever. some gave no history of contact with infected animals and it is presumed that they were infected by mosquitoes. complications were common. retinitis clinically associat ...	1980	7192434
ocular disease resulting from infection with rift valley fever virus.	the demonstration of serological conversion to rift valley fever (rvf) virus in paired acute and convalescent sera established rvf as the cause of two cases of retinitis seen during the 1977 rvf epidemic in egypt. colour photography of the retina revealed macular, paramacular and extramacular exudate-like lesions with associated haemorrage and oedema. one patient has not recovered central vision during a six-month convalescence. an ongoing study of a larger group of rvf patients with ocular dise ...	1980	7192443
adjuvant activity of a novel metabolizable lipid emulsion with inactivated viral vaccines.	studies were conducted in mice, hamsters, sheep, and two species of nonhuman primates which demonstrate the adjuvant activity of a new metabolizable lipid emulsion with marginally immunogenic doses of formalin-inactivated viral vaccines. the lipid base consists of highly refined peanut oil emulsified in aqueous vaccines with glycerol and lecithin. hamsters and mice inoculated with lipid emulsion plus western or venezuelan equine encephalitis vaccine were significantly more resistant than vaccina ...	1980	6772571
[rift valley fever. a threat for middle europe?].		1980	7191369
[retinal abnormalities caused by rift valley fever virus].		1980	7192368
experimental transmission and field isolation studies implicating culex pipiens as a vector of rift valley fever virus in egypt.	attempts were made to isolate virus from wild caught mosquitoes during the 1977 and 1978 rift valley fever (rvf) epizootics in egypt. over 95% of the 55,126 mosquitoes collected from epizootic areas in the nile delta and valley were culex pipiens. two strains of rvf virus were isolated from unengorged female c. pipiens taken in 1978. laboratory-reared c. pipiens originating from a population sample from the nile delta epizootic area transmitted rvf virus. the infection rate of mosquitoes that fe ...	1980	7446827
rift valley fever virus infection in man in nigeria.		1980	7229623
rift valley fever ocular manifestations: observations during the 1977 epidemic in egypt.	ocular manifestations resulting from rift valley fever (rvf) virus infection were studied during an extensive rvf epidemic in egypt during 1977. colour photography and fluorescein angiography of 7 serologically diagnosed patients showed the commonest manifestations to be macular, paramacular, and/or extramacular retinal lesions, often occurring bilaterally. haemorrhage and oedema were frequently associated with the lesions, and vasculitis, retinitis, and vascular occlusion were also observed. pa ...	1980	7192158
characterization of some ungrouped viruses.	bangui, bobaya, kowanyama, upolu and zinga are enveloped spherical rna viruses sensitive to ether and acid ph; morphologically resembling bunyaviridae, their diameters range from 90 to 100 nm and their bouyant density is 1.17 to 1.18 g/ml in sucrose. st. floris, a bunya-like virus, serologically related to rift valley fever, has a diameter ranging from 90 to 110 nm. triniti, zingilamo, ipym 120 and virus strain anb4268 are enveloped spherical rna viruses sensitive to ether and acid ph, have diam ...	1981	7330941
synthesis and antiviral activity of certain 9-beta-d-ribofuranosylpurine-6-carboxamides.	to examine the structural parameters necessary for antiviral efficacy of certain purine nucleosides, several 9-beta-d-ribofuranosylpurine-6-carboxamides have been synthesized. glycosylation of the me3si derivative of purine--6-carboxamide with protected ribofuranose in the presence of a lewis acid gave the blocked nucleoside which on deprotection furnished 9-beta-d-ribofuranosyl-6-iodopurine with cyanide ion. certain 2-amino- and 2-methyl-9-beta-d-ribofuranosylpurine-6-carboxamides have also bee ...	1981	7328597
arbovirus infections among laboratory personnel in ibadan, nigeria.	laboratory-acquired infections encountered between 1963 and 1977 among personnel of the virus research laboratory, ibadan, nigeria, are reported. two cases of chikungunya infection occurred and one each with dugbe, wesselsbron, and dengue viruses. in each case, virus was isolated or development of antibody demonstrated. among virus and two each to chikungunya and rift valley fever viruses, without experiencing any clinically recognized disease.	1981	7196163
a comparison of indirect immunofluorescence and electron microscopy for the diagnosis of some haemorrhagic viruses in cell cultures.	yellow fever, dengue (types 1, 2 and 4), chikungunya, rift valley fever, ebola, marburg, and lassa viruses were inoculated into susceptible cell cultures and daily investigated by indirect immunofluorescence (ifa) and electron microscopy (em) with a view to achieve an early detection-identification of these agents. compared to the other cell lines tested (vero, bhk-21 and aedes albopictus), cv-1 cells were found to be more sensitive. viral antigens were detected by ifa from a few hours post inoc ...	1981	7024293
[hematophagous diptera arbovirus vectors in africa (author's transl)].	the authors, in a first part, show the general arthropods-viruses-vertebrates relationships and specially the different conditions of virus maintenance in the selvatic foci. then they succinctly give the main characteristics of the vectors bioecology useful for understanding the epidemiology of arbovirus diseases of man and domestic animals. thus diptera vectors of o'nyong-nyong and chikungunya fevers, yellow fever, dengue fever, wesselsbron, sindbis, and west nile viruses, rift valley fever, sa ...	1981	6116145
respiratory infectivity of a recently isolated egyptian strain of rift valley fever virus.	the respiratory infectivity of a strain of rift valley fever virus isolated in egypt (strain zh-501) was compared with that of one isolate from uganda (entebbe strain) and two isolates from south africa (strains sa-51 and sa-75). studies were performed with icr mice which were infected by exposure to infectious aerosols composed of particles with a mass median diameter of 0.96 micrometer. the respiratory median lethal doses for zh-501, entebbe, sa-51, and sa-75 were 2.2, 1.9, 2.6, and 1.9 log10 ...	1981	7287187
rift valley fever retinitis.	a 57-year-old dutch woman, who had lived and worked in tanzania for 26 years, developed serious, progressive bilateral retinitis after suffering from a fever of unknown origin. fundus abnormalities in both eyes suggested that the woman had been infected with rift valley fever virus. serologic studies confirmed this suspicion. white macular lesions accompanied to extensive vasculitis appear to be specific for rift valley fever retinitis.	1981	7196157
antibodies to rift valley fever virus in the human population of sudan.		1981	7196612
abortion in vaccinated sheep and cattle after challenge with rift valley fever virus.		1981	7340068
experimental infection of the african buffalo with the virus of rift valley fever.		1981	7344184
rift valley fever virus vaccine trial: study of side-effects in humans.		1982	7201671
marburg, ebola and rift valley fever virus antibodies in east african primates.	sera from 464 primates held at four institutes in kenya were tested by indirect immunofluorescence for the presence of antibodies against marburg, ebola, congo haemorrhagic fever, rift valley fever and lassa viruses. four of 136 vervet monkeys were positive for marburg virus antibodies and three of 184 baboons had antibodies against ebola virus. one baboon was positive for marburg virus antibodies. two vervet monkeys, three baboons and one grivet monkey (of 56 tested) had antibodies against rift ...	1982	6810518
a serological survey for rift valley fever antibody in food animals in kaduna and sokoto states of nigeria.	a total of 1106 serum samples from cattle, sheep, goats and camels were collected from kaduna and sokoto states of nigeria. these were tested for the presence of antibody to rift valley fever virus by the agar gel immunodiffusion method. the antibody prevalence rates were 2.85% in cattle, 6.67% in sheep, 0.98% in goats and 3.13% in camels.	1982	6820360
the spread of rift valley fever and approaches to its control.	rift valley fever (rvf) is primarily a disease of sheep, cattle, other domestic animals, and man; it was believed to be relatively benign for man until 1977 when it spread to egypt. there it caused enormous losses of sheep and cattle, and thousands of human cases occurred, with nearly 600 reported deaths. although mosquitos are known to transmit rvf virus in epizootics and epidemics, the reservoir and means of inter-epizootic maintenance are not known. rvf epizootics can be recognized by a combi ...	1982	6982772
rift valley fever, egypt 1977: disease spread by windborne insect vectors?		1982	7064329
rift valley fever: an emerging human and animal problem.		1982	7102093
sequential development of the liver lesions in new-born lambs infected with rift valley fever virus. i. macroscopic and microscopic pathology.	ten new-born lambs were necropsied at various intervals after artificial infection with rift valley fever virus for the study of the sequential development of the hepatic lesions. during the late stage of the disease, the livers were slightly to moderately swollen and mottled yellow, orange-brown and red. greyish-white foci, approximately 0,25-0,5 mm in diameter, were also scattered throughout the parenchyma. microscopically, the liver lesions progressed from sparsely distributed acidophilic bod ...	1982	7177580
sequential development of the liver lesions in new-born lambs infected with rift valley fever virus. ii. ultrastructural findings.	the macroscopic and microscopic lesions in livers of new-born lambs experimentally infected with rift valley fever virus and killed at various intervals between 6-53 h after inoculation, were described in a previous paper. this communication gives an overview of the ultrastructural changes affecting hepatocytes, sinusoids and spaces of disse, biliary tree and portal triads as well as observations on the morphology and morphogenesis of the virus. hepatocytes were those primarily affected, while i ...	1982	7177581
inhibition of rna viruses in vitro and in rift valley fever-infected mice by didemnins a and b.	didemnins, a new class of depsipeptides isolated from a caribbean tunicate, have been shown to have potent antiviral activity against a broad range of rna viruses in vitro. didemnins a and b both protected mice against a lethal challenge of rift valley fever virus.	1982	7188246
clinical and pathological studies in adult sheep and goats experimentally infected with wesselsbron disease virus.	the clinical symptoms and pathology in 33 adult sheep and 31 adult goats experimentally infected with wesselsbron disease virus are described. there was moderate to severe hyperthermia in most animals, but no other clinical signs of disease or deaths were recorded. eleven sheep and 6 goats were sacrificed for pathological studies at various stages during the febrile response. the macroscopic and microscopic lesions in these cases are described. microscopic studies revealed that the liver was con ...	1982	6289220
recombinant dna technology for the preparation of subunit vaccines.	recombinant dna technology appears to be on the verge of producing safe and effective protein vaccines for animal and human diseases. the procedure is applicable to most viruses because their isolated surface proteins generally possess immunogenic activity. strategies used for the preparation and cloning of the appropriate genes depend on the characteristics of the viral genomes: whether dna or rna; their size, strandedness, and segmentation; and whether messenger rna are monocistronic or polyci ...	1982	6129235
[recent research progress on interferon].		1982	6180965
identification of a major non-structural protein in the nuclei of rift valley fever virus-infected cells.	a non-structural protein of mol. wt. 34 x 10(3) was demonstrated in the nuclei of rift valley fever virus-infected vero cells by sds-polyacrylamide gel electro-phoresis. the protein appears to correspond to the virus-induced antigen demonstrated by indirect immunofluorescence in intranuclear inclusions.	1982	7108491
studies on the antigenic relationship among phleboviruses.		1982	6174048
antiviral efficacy of pyrazofurin against selected rna viruses.	the antibiotic pyrazofurin, 3-(beta-d-ribofuranosyl)-4-hydroxypyrazole-5-carboxamide, markedly inhibited the in vitro replication of a number of rna viruses including rift valley fever (rvf), venezuelan equine encephalomyelitis (vee), sandfly, pichinde, lassa and lcm virus. plaque formation was reduced by 80% or more with 2-10 micrograms/ml of pyrazofurin while 2 micrograms/ml reduced by 1000-fold the yield of lassa and lcm virus in a yield reduction assay. in vivo, pyrazofurin failed to protect ...	1982	6299188
the hemorrhagic fevers of southern africa with special reference to studies in the south african institute for medical research.	in this review of studies on the hemorrhagic fevers of southern africa carried out in the south african institute for medical research, attention has been called to occurrence of meningococcal septicemia in recruits to the mining industry and south african army, to cases of staphylococcal and streptococcal septicemia with hemorrhagic manifestations, and to the occurrence of plague which, in its septicemic form, may cause a hemorrhagic state. "onyalai," a bleeding disease in tropical africa, ofte ...	1982	6897472
inbred rat strains mimic the disparate human response to rift valley fever virus infection.		1982	7130966
a rift valley fever vaccine trial. i. side effects and serologic response over a six-month follow-up.	a formalin-inactivated rift valley fever vaccine, originally produced in primary monkey kidney cells, has been used to protect laboratory workers. a trial of a modified vaccine, newly formulated in well-characterized diploid fetal rhesus lung cells, was conducted with 114 men aged 19--24 years. of the 107 subjects who received up to three injections of 0.1 to 1 ml vaccine (an additional seven received a placebo) one had a local hypersensitivity-type reaction and another a generalized urticarial ...	1982	6890766
the susceptibility of culicoides variipennis coq. (diptera: ceratopogonidae) to laboratory infection with rift valley fever virus.	the vector potential of culicoides variipennis for rift valley fever virus (rvfv) was investigated. insects from a colony maintained at the animal virus research institute, pirbright, were fed through a membrane on a mixture of mouse blood and rvfv (virus concentration of blood meal 7 x 95 log10 mld50ml). engorged insects were maintained at 25 degrees c +/- 1 degrees c. samples of insects were tested at daily intervals to determine their virus content. four of the five females tested immediately ...	1982	7179410
a serological survey of rift valley fever antibodies in the northern sinai.	in the aftermath of an extensive egyptian rift valley fever (rvf) epidemic during 1977-78, rvf activity in the adjacent sinai peninsula has been inferred from the presence of haemagglutination-inhibition (hi) antibodies in sera from indigenous humans and rodents. we attempted to confirm these findings by hi testing of sera from israeli soldiers serving in the region of the el arish wadi system in the sinai, and from indigenous rodents. six of 199 human sera (3.0%) and two of 88 rodent sera (2.3% ...	1982	6926758
reduced pathogenicity associated with a small plaque variant of the egyptian strain of rift valley fever virus (zh501).	variants of rift valley fever virus producing plaques in cer cells of four different sizes are described. a plaque-forming unit (pfu) variant forming minute plaques was isolated and purified. virus derived from this variant was not pathogenic to adult swiss albino mice by the intraperitoneal (i.p.) route and was less pathogenic than the parent strain (zh501) to adult sprague dawley rats by i.p. route, but produced typical severe liver necrosis in adult syrian hamsters with intranuclear and intra ...	1982	6926765
the effect of laboratory colonization on the vector-pathogen interactions of egyptian culex pipiens and rift valley fever virus.	field and laboratory findings implicated culex pipiens as a vector of rift valley fever (rvf) virus during the 1977-1978 epizootics/epidemics in egypt. this study evaluated changes in infection and transmission rates, and viral titers in f1 through f16 generation cx. pipiens mosquitoes orally infected with rvf virus. infection and transmission rates of rvf virus by this species changed significantly during the colonization process. however, the ultimate viral titers of either the transmitting or ...	1983	6625070
viral haemorrhagic fever surveillance in kenya, 1980-1981.	following two cases of marburg virus disease in kenya in 1980, viral haemorrhagic fever surveillance was undertaken in western kenya. over a 21-month period investigations, including virus isolation attempts, patient and contact serology, visits to areas where suspected cases occurred, interviewing family members and neighbours of suspected cases and following up any additional illnesses in these areas, were carried out. during the study two cases were found that were likely to have been ebola h ...	1983	6684336
characterization of eight new phlebotomus fever serogroup arboviruses (bunyaviridae: phlebovirus) from the amazon region of brazil.	eight new members of the phlebotomus fever arbovirus serogroup (family bunyaviridae; genus phlebovirus) from the amazon region of brazil are described. one serotype was recovered from a febrile patient, three from small wild animals and four from sand flies. a small serum survey carried out with the human isolate, alenquer virus, suggests that it rarely infects man. complement-fixation and plaque reduction neutralization tests were done, comparing the eight new viruses with other members of the ...	1983	6312820
antibodies against haemorrhagic fever viruses in kenya populations.	human sera from lodwar (77 sera), nzoia (841 sera), masinga (251 sera), laisamis (174 sera) and the malindi/kilifi area (556 sera) in kenya were tested by indirect immunofluorescence for antibodies against marburg, ebola (zaire and sudan strains), congo haemorrhagic fever, rift valley fever and lassa viruses. antibodies against ebola virus, particularly the zaire strain, were detected in all regions and were, over-all, more abundant than antibodies against the other antigens. ebola and marburg a ...	1983	6419422
zinga virus: a strain of rift valley fever virus.		1983	6403821
monoclonal antibodies to identify zinga virus as rift valley fever virus.		1983	6131312
serological evidence of endemic zinga virus and rift valley fever virus in central african republic.		1983	6134127
reversed passive hemagglutination and inhibition with rift valley fever and crimean-congo hemorrhagic fever viruses.	reversed passive hemagglutination (rpha) tests were performed by coating glutaraldehyde-fixed and tannic acid-treated sheep erthrocytes with antibodies to rift valley fever (rvf) and crimean-congo hemorrhagic fever (cchf) viruses. cells coated with crude antibody, in the form of mouse immune ascitic fluid, reacted with high specificity and sensitivity in rpha tests with live or inactivated virus antigens. in inhibition (rphi) tests, rvf antibody titers in human and sheep sera were similar to tho ...	1983	6407347
detection of rift valley fever virus antigen by enzyme-linked immunosorbent assay.	a double-antibody (sandwich) enzyme-linked immunosorbent assay (elisa) was adapted to detect rift valley fever virus antigen. antibodies were purified from hyperimmune mouse and rabbit sera by affinity chromatography, using cnbr-activated sepharose 4b coupled to a beta-propiolactone-inactivated sucrose-acetone-extracted suckling mouse liver antigen. in the assay, antigen was captured by mouse antibody adsorbed to polystyrene plates and then detected by reacting sequentially with rabbit anti-rift ...	1983	6409920
rift valley fever and its epidemiology in egypt: a review.		1983	6577119
the use of veterinary vaccines for prevention and control of rift valley fever: memorandum from a who/fao meeting.	this memorandum considers the use of veterinary vaccines for the prevention of rift valley fever (rvf) and for its control during outbreaks. veterinary vaccines are the first line of defence against rvf. existing live and inactivated vaccines have been used extensively in africa but further development of both is warranted. the live virus vaccine may cause abortion and its potential for reversion to virulence has not been adequately investigated. it should be used only in enzootic and epizootic ...	1983	6602663
[use of veterinary vaccines for preventing and combatting rift valley fever: memorandum of a who/fao meeting].		1983	6603918
broad-spectrum antiviral activity of 2-beta-d-ribofuranosylselenazole-4-carboxamide, a new antiviral agent.	the relative in vitro antiviral activities of three related nucleoside carboxamides, ribavirin (1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamide), tiazofurin (2-beta-d-ribofuranosylthiazole-4-carboxamide), and selenazole (2-beta-d-ribofuranosylselenazole-4-carboxamide), were studied against selected dna and rna viruses. although the activity of selenazole against different viruses varied, it was significantly more potent than ribavirin and tiazofurin against all tested representatives of the ...	1983	6615611
rift valley fever.		1983	6359835
replication and dissemination of rift valley fever virus in culex pipiens.	following ingestion of 10(4.2) to 10(7.2) plaque-forming units (pfu) of rift valley fever (rvf) virus, 662 of 850 female culex pipiens (78%) became infected. those mosquitoes that became infected separated into two distinct groups: 1) those with a nondisseminated infection limited to the gut, and 2) those with a disseminated infection. the former group contained a median of 10(3.2) pfu, while those females with a disseminated infection contained a median of 10(5.5) pfu. only those females with a ...	1984	6696176
protein synthesis in rift valley fever virus-infected cells.	rift valley fever virus-induced protein synthesis was examined by polyacrylamide gel electrophoresis and fluorography. five virus-induced polypeptides were detected, the nucleocapsid protein n, the nucleus-associated nonstructural protein ns1, the glycoproteins g1 and g2, and a protein of molecular weight 80k. the n, g1, g2, and 80k proteins were present in virion preparations. sequential studies showed that ns1 accumulated in the nucleus as soon as it was formed and readily associated with nucl ...	1984	6710870
replication of rift valley fever virus in the sand fly lutzomyia longipalpis.	rift valley fever virus was shown to replicate in lutzomyia longipalpis after intrathoracic inoculation. viral titers peaked at approximately 4 days postinoculation [mean titer = 10(4.0) plaque forming units (pfu)] and remained relatively constant through day 7. a minimum of 6 of 326 sand flies transmitted virus by bite to susceptible hamsters after 5-9 days of extrinsic incubation. viral titers of sand flies exposed per os declined steadily through day 9. none of 378 flies that had ingested app ...	1984	6711746
active and passive immunization against rift valley fever virus infection in syrian hamsters.	the protection by active and passive immunization of golden syrian hamsters challenged with rift valley fever (rvf) virus intraperitoneally was studied. six groups of 10 hamsters were inoculated with different amounts of immune serum while five groups were actively immunized with different doses of a formalin-inactivated rvf vaccine. one day after passive and three weeks after active immunization all hamsters were challenged with 5000 plaque-forming units of rvf virus. plaque reduction neutraliz ...	1984	6507105
preliminary survey of domestic animals of the sudan for precipitating antibodies to rift valley fever virus.	in a preliminary seroepidemiological survey a total of 780 serum samples derived from various domestic animals of the sudan were examined for rift valley fever (rvf) virus precipitating antibodies. the incidence was approximately 34.3% in sheep, 33.2% in cattle, 22% in goats, 7.9% in camels and 4% in donkeys. the findings indicated that rvf is mainly prevalent in the rich savanna areas of the south as well as the irrigated areas close to the nile in the north. circumstantial evidence suggests th ...	1984	6512261
[rift valley fever and zinga virus: a pathogenic arbovirus in man and animal new for madagascar].	virus zinga strains have been isolated from several pools of mosquitoes collected in perinet area, 130 km far from tananarive, at the institut pasteur of madagascar in 1980. although this virus is pathogenic for man, it seemed to give only a mild illness and did not appear to constitute a problem of public health. but today it is seen in quite a different way; since the who center for arbovirus reference and research of new haven has shown the serologic identity between virus zinga and an anothe ...	1984	6534285
detection of human immunoglobulins g and m antibodies to rift valley fever virus by enzyme-linked immunosorbent assay.	rift valley fever virus (rvfv) is an important human and animal pathogen in africa and has been responsible for infections in travelers. because of the aerosol infectivity and risk of dissemination of the virus, a need exists for simple, safe, serological tests for diagnosis. an enzyme-linked immunosorbent assay (elisa) was developed to detect rvfv-specific immunoglobulins (immunoglobulin g [igg] and igm). in the test, a betapropiolactone-inactivated, sucrose-acetone-extracted, suckling mouse li ...	1984	6538206