Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ARBOVIRUS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1984

[Serologic survey on arbovirus infections in patients presenting with uveitis].

Viruses have been demonstrated or suspected as the causative agents of various types of uveitis. Some arboviruses can be responsible for ocular manifestations. In Brittany, both serosurveys and virus isolations were positive for arboviruses. These results led us to look for the possible role of arboviruses in the aetiology of uveitis. For this, we performed a serosurvey on 131 patients with uveitis of unknown aetiology. Patients were examined in the Ophthalmologic Department of the Brest University Hospital from May 1979 to May 1983. Serum samples were studied: by haemagglutination inhibition (HI) tests against thirteen antigens; by complement fixation (CF) tests against six antigens. The HI and CF tests were performed using micromethods. HI tests revealed antibodies against one or more flaviviruses antigens in thirteen patients: nine monospecific reactions against Yellow Fever virus (as a consequence of a vaccination) and four reactions against several flaviviruses. The four positive reactions are easily explainable by previous trips in countries where several arboviruses are endemic. By CF test we found antibodies at a low titer in two patients: the first one had antibodies against the Zaliv Terpeniya virus and the second against the Avalon virus. Signification of these results is discussed. Our study shows that in Brittany uveitis of unknown aetiology do not seem to be due to arboviruses, at least those tested in this survey or antigenically related.

Adolescent↗
PubMedDate not supplied

[Arboviruses - structure and classification (author's transl)].

The larger, biologically defined, set of arboviruses contains sub-sets representative of a number of different taxons. Arboviruses classified on serological grounds into Groups A and B are now placed respectively into the genera alphavirus and flavivirus, which form part of the family Togaviridae. The recently defined family Bunyaviridae contains almost 200 different arboviruses, serologically divisible into at least 24 different serogroups. The family Reoviridae includes the genus orbivirus which covers at least 17 serological groups, and the family Rhabdoviridae is another major family which contains a significant number of arboviruses. Outside these four families individual arboviruses are placed are placed in the families Iridoviridae, Poxviridae, Picornaviridae and Coronaviridae, but a least 50 arbovirueses remain unclassified.

Animals↗
PubMed1971

Immunological surveys of arbovirus infections in South-East Asia, with special reference to dengue, chikungunya, and Kyasanur Forest disease.

Serological surveys have been widely used in South-East Asia to determine the presence and activity of arboviruses. The haemagglutination-inhibition test has been most frequently employed but complement-fixation and neutralization tests have also been used in some investigations.Although virus isolations provide the most conclusive evidence, they can be carried out in a few specialized centres only, and serological surveys are very important for studying the distribution of arboviruses.The surveys have shown that group B arboviruses (principally all four types of dengue, Japanese encephalitis, and West Nile) are widely prevalent. Dengue and Japanese encephalitis viruses are more widespread than West Nile virus, which was not known previously to extend east of India although recent survyes have shown that its range extends to Burma. Japanese encephalitis is frequent in most of South-East Asia but in India is found mainly in eastern and south-eastern parts of the country. Kyasanur Forest disease (KFD) and Langat viruses are the only tick-borne group B arboviruses definitely known to occur in the region, the former in India, the latter in Malaysia. KFD virus has been isolated only from a small focus in Mysore, although human and animal sera containing neutralizing antibodies to this virus have been found sporadically in widely scattered areas. Among the group A arboviruses, chikungunya and Sindbis have been detected in serological surveys, but the former has not yet been found in Malaysia.

Adolescent↗
PubMed2002

Isolation of eastern equine encephalitis virus and West Nile virus from crows during increased arbovirus surveillance in Connecticut, 2000.

The emergence of the West Nile virus (WNV) in the northeastern United States has drawn emphasis to the need for expanded arbovirus surveillance in Connecticut. Although the state of Connecticut began a comprehensive mosquito-screening program in 1997, only since 1999 have there been efforts to determine the prevalence of arboviruses in bird populations in this state. Herein, we report on our results of an arbovirus survey of 1,704 bird brains. Included in this report are the first known isolations of eastern equine encephalitis virus (EEEV) from crows and data on the geographic and temporal distribution of 1,092 WNV isolations from crow species. Moreover, these nine isolations of EEEV identify regions of Connecticut where the virus is rarely found. With the exception of WNV and EEEV, no other arboviruses were isolated or detected. Taken together, these data illustrate the distribution of avian borne EEEV and WNV in 2000 and support the need for ongoing avian arbovirus surveillance in Connecticut.

Animals↗
PubMed2005

Arbovirus circulation, temporal distribution, and abundance of mosquito species in two Carolina bay habitats.

Carolina bays, a type of geomorphic feature, may be important in the ecology of mosquito vectors in South Carolina. Their hydrology varies from wetland habitats with marked flooding/drying regimes to permanently flooded spring-fed lakes. Moreover, they possess characteristics that contribute to the support of a particularly abundant and diverse invertebrate fauna. Although it has been estimated that 2,700+ bays exist in South Carolina, approximately 97% have been altered; < or = 200 bays remain intact, and only 36 are protected by state-funded conservation projects. We conducted a study in two distinct Carolina bay habitats, Savage Bay Heritage Preserve (SBHP) and Woods Bay State Park (WBSP), from June 1997 to July 1998 to determine mosquito temporal distribution, species composition, and the occurrence of arbovirus activity. The largest mosquito collection was obtained at WBSP (n = 31,172) representing 25 species followed by SBHP (n = 3,940) with 24 species. Anopheles crucians complex were the most common species encountered in both bays. Two virus isolates were obtained from SBHP in 1997: Keystone (KEY) virus from Ochlerotatus atlanticus-tormentor and Cache Valley (CV) virus from Oc. canadensis canadensis. Twenty-nine (29) arbovirus-positive pools were obtained from WBSP: 28 in 1997 and one in 1998. KEY virus was isolated from three pools of Oc. atlanticus-tormentor and Tensaw (TEN) virus was isolated from two pools of An. crucians complex; 10 isolates could not be identified with the sera available. Additionally, 14 pools of An. crucians complex tested positive for Eastern equine encephalitis (EEE) virus antigen. These represent the first record of KEY and CV viruses in South Carolina. Our data indicate the presence of high mosquito density and diversity in both Carolina bay habitats, which may be influenced, in part, by seasonal changes in their hydroperiods. The study of mosquito and arbovirus ecology in Carolina Bay habitats could provide more information on the transmission dynamics of arboviruses and its impact on human and animal arboviral disease occurrence in South Carolina.

Aedes↗
PubMed2000

[Serological survey on arbovirus infection in residents of an ecological reserve].

OBJECTIVE: Serological inquires conducted in the Ribeira Valley, S. Paulo State, Brazil, showed an intense circulation of pathogenic arboviruses in the region. The goal was to verify the prevalence of arboviral infections in people living at the local ecological, and its potential association with these population' individual and familiar characteristics. METHODS: The study was carried out among 182 persons of 58 families to identify the presence of antibodies to the following viruses: Rocio (ROC), Ilheus (ILH), Eastern equine encephalitis virus (EEE), Western equine encephalitis virus (WEE), Venezuelan equine encephalitis virus (VEE) and St. Louis encephalitis virus (SLE). Inhibition hemagglutination test and plaque reduction neutralization test were the laboratory assays of choice. MAC-ELISA was used to identify IgM antibodies to ROC, ILH and EEE viruses. RESULTS: The prevalence of antibodies was 26.9% (21. 4% to alphavirus and 12.6% to flavivirus). There were no antibodies to WEE virus. IgM antibodies were not observed suggesting no recent infection in study population. Among the characteristics investigated, age, occupation, place of birth and the habit of going into the forest were shown to be statistically associated with arboviral infection (p<0.05). CONCLUSIONS: It was observed an intense circulation of pathogenic arboviruses, especially VEE. It seems the habit of going into the forest is the most important factor to this population exposure to the mosquito vectors of arboviruses. The results suggest the need of further investigation to clarify the role of birds as arbovirus infection amplificators indoors.

Adolescent↗
PubMed1976

Arbovirus infection in a Murray Valley community. I. Prevalence of antibodies, December, 1974.

A survey of antibodies to Group A and Group B arboviruses (also designated as alphaviruses and flaviviruses respectively) was performed in residents of a Murray Valley town eight months after an outbreak of arbovirus illnesses in other parts of the region. The sampling pattern was based upon a random selection of households. The prevalence of Group A antibodies rose steadily with relation to age. The prevalence of Group B antibodies was much lower in all age groups, and did not show such a consistent rise with age. No Group B antibodies were found in younger residents. This suggests either an unexpectedly rapid decay of the particular type of antibody in this age group, or regional variations in the prevalence of arbovirus which are not currently understood. Some individuals appear to be unusually exposed to arbovirus infection.

Adolescent↗
PubMedDate not supplied

[The mammals of Guinea as reservoirs and carriers of arboviruses].

A great body of data on the fauna and ecology of wild mammals and their participation in the circulation of arboviruses were collected when the ecology of the latter of the Republic of Guinea was studied in 1978 to 1989. A hundred and eighteen species belonging to 10 orders were identified. Over 2,000 biological specimens were virologically and serologically examined. Six arboviruses were isolated. These included Dugbe virus (from the hussar monkey Cercopithecus (Erythrocebus patas) and 5 viruses from chiropters: Rift valley fever, from Micropteropus pusillus, Miniopterus schreibersi, and Hipposideros caffer, Saboya, Fomede, and Ank 6909 from Nycteris gambiensis and Kolenter from Hipposideros sp. Fomede, Kolente, and Ank 6909 viruses turned out to be new species for science. Rodents were found to have viral antigens of Lass fever (Mastomys natalensis, Tatera valida kempi and Rattus rattus), Dugbe and Chikungunya fevers (M. natalensis) and West Nile fever (Mus sp.). A serological survey of mammals revealed that the latter had antibodies to 12 arboviruses. Thus, the mammals of Guinea participate in the circulation of 18 arboviruses, 13 of them are pathogenic for man.

Animals↗
PubMedDate not supplied

[A seroepidemiologic and virological study of the presence of arboviruses in Moldavia in 1961-1982].

In Romania, St. Drăgănescu et al., Miszkolczy et al., based on clinical and epidemiological observations, affirmed the possible presence of "tick-borne encephalitis (TBE)". However, critical retrospective evaluation of certain others' papers published through 1958-1971 reveal some uncommon features. By way of example: a very high incidence of CF- and HI-antibodies in acute and chronic CNS illnesses as well as in general population; replication in nucleus and maturation in mitochondria of a strain of "TBE virus" isolated from a patient CSF; isolation of "group B arbovirus" from Ixodes persulcatus on Romanian territory. As known, this tick was not identified in Romania, "no tick-borne Flavivirus isolated outside the U.S.S.R. proved to be a strain of RSSE virus" and "no arbovirus (Alpha- and Flavivirus or Bunyavirus) was ever detected in nucleus". Based on the HI reaction with West Nile (WN) virus, strain Egypt 101, human, domestic and wild vertebrates sera, treated with acetone for removal of nonspecific inhibitors, were tested as part of a control study, in Moldavia in 1961. WN virus was selected for its capacity to crossreact in the HI test with many members of the family Flaviviridae, genus Flavivirus (formerly Group B arboviruses), including the agents of Central European encephalitis. In order to avoid the interference of nonspecific inhibitors, a new single radial haemolysis test for the assay of antibodies to haemagglutinating arboviruses was calibrated in 1979. The seroepidemiological study performed on all 19.853 sera (10.698 human, 6.452 domestic mammals, 2.477 wild small rodents and 226 migrating aquatic birds) pointed out a very low circulation of Flaviviruses in the investigated area. The attempts to isolate such viruses from Ixodes ricinus on suckling mice yielded a single strain of Kemerovo (genus Orbivirus) virus. The need of extending the study to other viruses transmitted by arthropods and rodents, and mainly on the haemorrhagic fever with renal syndrome, an illness already clinically identified in Moldavia, is emphasized. Final consideration of viability (specificity, sensitivity, accuracy and precision) of the tests used and the need for continuous quality control is also presented.

Antibodies, Viral↗
PubMed1986

Post-encephalitic epilepsy and arbovirus infections in an isolated rainforest area of central Liberia.

Among a population of 4.436 Bassa, Kpelle and Mano people in the Gbawein and Wroughbarh Clan region of Grand Bassa Country, Liberia, 123 cases of epilepsy could be documented. In 38% of these cases infections involving the central nervous system precipitated the onset of seizures. Sera from 67 epilepsy patients, 50 direct healthy relatives and 22 geographically matched controls were tested for antibodies to 16 arboviruses of the Togaviridae and Bunyaviridae known to occur in Africa. Antibodies to arboviruses were found in 16.5% of the epilepsy patients, 36% of the mostly older family members, and in 22% of the controls. Males and females were equally affected as were the different clans and language groups. Although meningoencephalitis with sequelae, like seizures, are known to result from arbovirus infections, no evidence for a correlation between epilepsy in this are of Central Liberia and previous arbovirus infection could be established.

Adolescent↗
PubMedDate not supplied

[Sero-epidemiological survey of arbovirus diseases in the Bi-Aka pygmies of Lobaye, Central African Republic].

Sero-epidemiological survey for Arboviruses among Bi-Aka Pigmies of the Lobaye, Central African Empire. A sero-epidemiological survey has been conducted, in 1975-1976, among 349 nomadic Pygmies of the Lobaye area in the Central African Empire, to investigate the prevalence of arbovirus infections. The percentages of individuals with detectable antibodies were 9,5 % for Chikungunya, 13,5 % for Semliki Forest, 5,2 % for Sindbis; 11,7 % for Bunyamwera; 2,3 % for West Nile, 6,3 % for Uganda S, and 8,9 % for Yellow Fever. These results are similar to those found in 1964 by CHIPPAUX in a comparable group of Pigmies of the same area and confirm that the prevalence of arbovirus infections is lower in the nomadic pygmies of the same area and confirm that the prevalence of arbovirus infections is lower in the nomadic Pygmies than in the sedentary Pygmies as well as in the settled bantus of the Lobaye valley villages. Yellow fever specific antibodies detected in this non vaccinated population indicate that latent infections occur in human beings living in the depth of the tropical forest, from the natural sylvatic focus of yellow fever, which remains active as recently proven in the Central African Empire by virus isolations obtained from wild caught mosquitoes.

Antibodies, Viral↗
PubMed1969

Arbovirus plaquing in a clonal line (PS Y-15) of porcine kidney.

Plaque development of 42 arbovirus serotypes, representing 17 serogroups, was studied in a clonal line (PS Y-15) of porcine kidney. The arboviruses plaqued within 3 to 7 days, with plaque diameters ranging from 1 to 5 mm. Mouse mortality and cell infectivity end points were compared with 24 arboviruses. Arbovirus LD(50) end points in mice exceeded the porcine kidney monolayer plaque-forming unitage end point with all 24 viruses compared.

Animals↗
PubMed1970

Arbovirus identification by an agar-gel diffusion technique.

A double diffusion-in-agar test was used to investigate precipitation reactions of 75 arboviruses. Specific reactions were regularly observed with members of arbovirus groups B, California, Simbu, Turlock, Hart Park, vesicular stomatitis, and several other arboviruses as well as with a member of the Tacaribe group and a herpesvirus. The results demonstrated the feasibility of applying this technique to the identification of arboviruses.

Agar↗
PubMed1975

Inhibition of group B arbovirus antigen production and replication in cells enucleated with cytochalasin B.

A comparative study of the growth of Sindbis (SIN) virus, a group A arbovirus (togavirus), and Japanese encephalitis (JE) virus, a representative group B arbovirus (togavirus), was conducted in enucleate and nucleate cells. Immunofluorescent tests and yield measurements demonstrated that chicken embryo cells which had been enucleated and subsequently infected with SIN virus produced virus-specific antigens and infectious virus. By contrast, JE failed to replicate or produce virus-specific antigen in cells which had been enucleated before or even 2 h post infection. Studies of the effect of enulceation at various times after infection demonstrated that a nucleus must be present at least 2 and possibly as long as 4 h after infection to produce either JE-specific antigen or infectious JE virus. These studies demonstrate that the replication of SIN, a group A arbovirus (togavirus), which has no nuclear requirement, contrasts sharply with that of a group B arbovirus (togavirus), JE, which may have an initial dependence on a nucleus-associated process.

Animals↗
PubMed2002

[Impact of global climate changes on arboviruses transmitted to humans by mosquitoes and ticks].

Global warming [+0.5-0.6 degree C during the second half of the 20th century] seems a reality although climatologists did not reach a common agreement on its actual origin, and this phenomenon may still increase along the 21st century [+1.5 to 6 degrees C]. Epidemiologists are anxious at the eventual effects of the resulting climate change on the evolution of arbovirus infections transmitted to human beings by hematophagous vectors such as mosquitoes and ticks. Analysis of the literature devoted to this problem did not lead to precise conclusions and the mathematical models used seems insufficient for they take into account mainly the climatic factors and not enough the human ones. Examples of dengue, european tick-borne encephalitis and other arbovirus infections are discussed. Peculiar attention is devoted to the eventual effects of climatic changes on the hibernation process in some small mammals and the timing of bird's migrations, involved in enzootic cycles of arboviruses. It is likely that arbovirus diseases may locally extend, both in latitude and altitude, leading to outbreaks, but regressions may also occur.

Animals↗
PubMed1990

Distribution of antibodies against Coxsackie B viruses, arboviruses and Toxoplasma gondii among patients with endomyocardial fibrosis (EMF) compared with normal subjects from EMF endemic and non-endemic zones of Nigeria.

The sera of eight endomyocardial fibrosis (EMF) subjects, 11 siblings of one of them and 16 normal children matched with the EMF patients for age, sex and socio-economic status from Ogunmakin and Shao/Oloru communities (eight each), situated in EMF-endemic and non-endemic areas of Nigeria respectively, were examined for the presence of antibodies against Coxsackie viruses B1-6, 16 arboviruses and Toxoplasma gondii. Sera from 36 other randomly selected normal children from Ogunmakin and 26 other randomly selected children from Shao/Oloru were also tested for the presence of antibodies against Toxoplasma gondii and the 16 arboviruses. None of the eight EMF subjects nor the 11 siblings of one of them had antibodies against any of the Coxsackie viruses B1-6 in their sera. Two of the 16 matched control subjects, one from each community, had positive antibodies, at equivocal titres against Coxsackie B1 (Ogunmakin) and B4 (Shao/Oloru). There was no significant difference in the distribution of antibody titres to the arboviruses between the EMF patients and matched controls. Normal children from the Shao/Oloru community had higher percentage antibody reactions and higher titres to the arboviruses compared with the children from Ogunmakin. All the eight EMF patients had high antibody titres against Toxoplasma gondii. Seven (87.5%) of the matched controls from Ogunmakin were sero-positive for Toxoplasma gondii compared with three (37.5%) of the matched controls from Shao/Oloru. Of the 36 normal children from Ogunmakin, 32 (88.9%) were sero-positive compared with 11 (42.3%) of the 26 normal children from Shao/Oloru. Four (36.4%) of the 11 siblings of one of the EMF patients had weak sero-positivity. It is therefore concluded that further studies are needed to clarify the role, if any, of Toxoplasma gondii in EMF.

Adolescent↗
PubMedDate not supplied

[Determination of arbovirus group affiliation in the indirect hemagglutination reaction].

A dry polyvalent erythrocyte immunoglobulin diagnostic preparation for arboviruses of Group B may be prepared to be used in the indirect hemagglutination test. The preparation detects antigens of arboviruses of this group in the tissue culture fluid and in suckling mouse brain tissue treated with sucrose-acetone. The test with Group B arbovirus antigens is inhibited specifically by the homologous polyvalent immune gamma globulin. Inhibition of hemagglutination by species-specific immune globulins to individual members of Group B arboviruses permits typing of tick-borne encephalitis birus only. In making the erythrocyte diagnostic preparation, the optimal concentration of the sensitizing immune gamma globulin should be determined experimentally.

Animals↗
PubMedDate not supplied

[Tick-borne arboviruses associated with marine birds; a general review (author's transl)].

About forty different arboviruses have been isolated from ticks associated with marine birds along all the coast of the world. The majority of these viruses belongs to 8 serogroups: Hughes, B, Kemerovo, Quaranfil, Nyamanini, Sakhalin, Unkuniemi and Upolu, while some others are non-grouped arboviruses. Two kinds of specialized ticks chiefly harbour these arboviruses: 1. The ticks of Ornitbodoros capensis complex from tropical, subtropical and temperate zones - 2. The ticks Ixodes uriae (= I. putus) and Ixodes signatus from subpolar, arctic and antarcitc zones and the surrounding temperate areas. All these ticks may attack humans, and severe pruritus and/or undifferenciated febrile illness may result. From a pathological point of view, some of these arboviruses, i.e. Soldado, Aride, Saumarez Reef, act as pathogens for marine birds inducing nest desertion and death or abnormal development of newly batched chicks. On the other hand, antibodies against other viruses, with well known or suspected epidemic potency, such as West Nile, Tyuleniy, Okhotskiy viruses, are currently found in human beings in certain coastal areas. These epidemiological data deserve further attention from concerned Health autorities.

Animals↗