Migratory birds (swallow, Hirundo rustica; sand martin, Riparia riparia; house martin, Delichon urbica) caught in southern Moravia (Czechoslovakia) in 1984-87 were examined for arbovirus infections. Isolation experiments were carried out using blood samples of 183 birds (52 swallows, 107 sand martins, and 24 house martins). The results were negative. Serological examinations of 136 birds (36 swallows, 86 sand martins, and 14 house martins) were made by haemagglutination-inhibition test (HIT) using 6 arboviral antigens of the genera Alphavirus (Sindbis--SIN) and Flavivirus (tick-borne encephalitis--TBE, West Nile--WN) and of the family Bunyaviridae (Tahyna--TAH, Calovo, CVO, and Bhanja--BHA). Antibodies against all of the tested viruses were detected at different rates: SIN 2.9%, TBE 1.5%, WN 1.5%, TAH 4.4%, CVO 1.5%, and BHA 2.2%. The titres ranged from 1.20 to 1.80.

• MeSH
• Alphavirus imunologie   MeSH
• arbovirové infekce epidemiologie   veterinární   MeSH
• arboviry imunologie   MeSH
• Bunyaviridae imunologie   MeSH
• Flavivirus imunologie   MeSH
• nemoci ptáků epidemiologie   MeSH
• protilátky virové krev   MeSH
• ptáci MeSH
• testy inhibice hemaglutinace MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Československo epidemiologie   MeSH
• Názvy látek
• protilátky virové MeSH

Sparrows from central Poland were examined by a hemagglutination-inhibition test (titer > or = 20) for the presence of antibodies to arboviruses, between 1995 and 1996. In house sparrows (Passer domesticus) (n = 179), antibodies to Sindbis, West Nile, tick-borne encephalitis, Tahyna, and Calovo viruses were detected at seroprevalences of 1.1%, 2.8%, 1.1%, 2.8%, and 1.1%, respectively. In tree sparrows (P. montanus) (n = 33), antibodies to the Sindbis, West Nile, and Tahyna viruses were detected at seroprevalences of 9.1%, 12.1%, and 3.0%, respectively.

• MeSH
• Alphavirus imunologie   MeSH
• arboviry imunologie   MeSH
• divoká zvířata MeSH
• Flavivirus imunologie   MeSH
• hospodářská zvířata MeSH
• Orthobunyavirus imunologie   MeSH
• protilátky virové krev   MeSH
• ptáci imunologie   virologie   MeSH
• roční období MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Polsko MeSH
• Názvy látek
• protilátky virové MeSH

RNA of Kyzylagach virus (KYZV), a Sindbis-like mosquito-borne alphavirus from Western equine encephalitis virus complex, was detected in four pools (out of 221 pools examined), encompassing 10,784 female Culex modestus mosquitoes collected at a fishpond in south Moravia, Czech Republic, with a minimum infection rate of 0.04%. This alphavirus was never detected in Central Europe before.

• Klíčová slova
• Culex modestus, Sindbis, alphaviruses, arboviruses, mosquito, reedbeds,
• MeSH
• Culicidae virologie   MeSH
• infekce alfaviry přenos   virologie   MeSH
• komáří přenašeči virologie   MeSH
• virus Sindbis * MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH

Defective viral genomes (DVGs) are truncated and/or rearranged viral genomes produced during virus replication. Described in many RNA virus families, some of them have interfering activity on their parental virus and/or strong immunostimulatory potential, and are being considered in antiviral approaches. Chikungunya virus (CHIKV) is an alphavirus transmitted by Aedes spp. that infected millions of humans in the last 15 years. Here, we describe the DVGs arising during CHIKV infection in vitro in mammalian and mosquito cells, and in vivo in experimentally infected Aedes aegypti mosquitoes. We combined experimental and computational approaches to select DVG candidates most likely to have inhibitory activity and showed that, indeed, they strongly interfere with CHIKV replication both in mammalian and mosquito cells. We further demonstrated that some DVGs present broad-spectrum activity, inhibiting several CHIKV strains and other alphaviruses. Finally, we showed that pre-treating Aedes aegypti with DVGs prevented viral dissemination in vivo.

• MeSH
• Aedes virologie   MeSH
• antivirové látky farmakologie   MeSH
• defektní viry genetika   MeSH
• genom virový * MeSH
• horečka chikungunya imunologie   přenos   virologie   MeSH
• komáří přenašeči virologie   MeSH
• lidé MeSH
• replikace viru * MeSH
• virus chikungunya genetika   růst a vývoj   izolace a purifikace   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• antivirové látky MeSH

The potential for transport and dissemination of certain pathogenic microorganisms by migratory birds is of concern. Migratory birds might be involved in dispersal of microorganisms as their biological carriers, mechanical carriers, or as carriers of infected hematophagous ecto-parasites (e.g., ixodid ticks). Many species of microorganisms pathogenic to homeothermic vertebrates including humans have been associated with free-living migratory birds. Migratory birds of diverse species can play significant roles in the ecology and circulation of some arboviruses (e.g., eastern and western equine encephalomyelitis and Sindbis alphaviruses, West Nile and St. Louis encephalitis flaviviruses), influenza A virus, Newcastle disease virus, duck plague herpes-virus, Chlamydophila psittaci, Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, Campylobacter jejuni, Salmonella enterica, Pasteurella multocida, Mycobacterium avium, Candida spp., and avian hematozoans. The efficiency of dispersal of pathogenic microorganisms depends on a wide variety of biotic and abiotic factors affecting the survival of the agent in, or disappearance from, a habitat or ecosystem in a new geographic area.

• MeSH
• bakteriální infekce přenos   veterinární   MeSH
• divoká zvířata * mikrobiologie   parazitologie   virologie   MeSH
• migrace zvířat * MeSH
• nemoci ptáků přenos   MeSH
• parazitární nemoci u zvířat přenos   MeSH
• ptáci MeSH
• virové nemoci přenos   veterinární   MeSH
• zdroje nemoci veterinární   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Mosquito-borne chikungunya virus (CHIKV) is a positive-sense, single-stranded RNA virus from the genus Alphavirus, family Togaviridae, which causes fever, rash and severe persistent polyarthralgia in humans. Since there are currently no FDA licensed vaccines or antiviral therapies for CHIKV, the development of vaccine candidates is of critical importance. Historically, live-attenuated vaccines (LAVs) for protection against arthropod-borne viruses have been created by blind cell culture passage leading to attenuation of disease, while maintaining immunogenicity. Attenuation may occur via multiple mechanisms. However, all examined arbovirus LAVs have in common the acquisition of positively charged amino acid substitutions in cell-surface attachment proteins that render virus infection partially dependent upon heparan sulfate (HS), a ubiquitously expressed sulfated polysaccharide, and appear to attenuate by retarding dissemination of virus particles in vivo. We previously reported that, like other wild-type Old World alphaviruses, CHIKV strain, La Réunion, (CHIKV-LR), does not depend upon HS for infectivity. To deliberately identify CHIKV attachment protein mutations that could be combined with other attenuating processes in a LAV candidate, we passaged CHIKV-LR on evolutionarily divergent cell-types. A panel of single amino acid substitutions was identified in the E2 glycoprotein of passaged virus populations that were predicted to increase electrostatic potential. Each of these substitutions was made in the CHIKV-LR cDNA clone and comparisons of the mutant viruses revealed surface exposure of the mutated residue on the spike and sensitivity to competition with the HS analog, heparin, to be primary correlates of attenuation in vivo. Furthermore, we have identified a mutation at E2 position 79 as a promising candidate for inclusion in a CHIKV LAV.

• MeSH
• atenuované vakcíny genetika   imunologie   MeSH
• biologická adaptace účinky léků   genetika   MeSH
• cytokiny metabolismus   MeSH
• heparitinsulfát farmakologie   MeSH
• molekulární modely MeSH
• mutace genetika   MeSH
• myši MeSH
• neutralizující protilátky imunologie   MeSH
• proteiny virového obalu genetika   MeSH
• statická elektřina MeSH
• substituce aminokyselin genetika   MeSH
• virové vakcíny genetika   imunologie   MeSH
• virulence genetika   MeSH
• virus chikungunya * účinky léků   genetika   imunologie   patogenita   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• atenuované vakcíny MeSH
• cytokiny MeSH
• heparitinsulfát MeSH
• neutralizující protilátky MeSH
• proteiny virového obalu MeSH
• virové vakcíny MeSH