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2.
Avian Pathol ; 49(4): 404-417, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32301627

RESUMO

Infectious laryngotracheitis virus (ILTV), an alphaherpesvirus, causes acute respiratory disease primarily infecting the upper respiratory tract and conjunctiva. Administration of live attenuated ILTV vaccines via eye drop, drinking water, or by coarse spray elicits protective mucosal immunity in the head-associated lymphoid tissues (HALT), of which conjunctiva-associated lymphoid tissue (CALT) and the Harderian gland (HG) are important tissue components. The trachea, a non-lymphoid tissue, also receives significant influx of inflammatory cells that dictate the outcome of ILTV infection. The objective of this study was to evaluate leukocyte cellular and phenotypic changes in the CALT, HG and trachea following ocular infection with a virulent ILTV strain. At 1, 3, 5, 7 and 9 days post-infection, CALT, HG, and trachea of 6-week-old specific pathogen free (SPF) chickens ocularly-exposed to vehicle or virulent ILTV strain 63140 were dissociated, the cells enumerated and then phenotyped using flow cytometry. The CALT had the highest viral genomic load, which peaked on day 3. In ILTV-infected birds, the CALT had a decreased percentage of leukocytes. This was reflected by decreased numbers of MHCI+MHCII-, MHCI+MHCIIlow+, and CD4+ cells, while IgM+ and MHCI+MHCIIHigh+ expressing cell populations increased. In the HG, the most notable change in cells from ILTV-infected birds was a decrease in IgM expressing cells and histologically, an increase in Mott cells. In summary, an acute, ocular exposure to ILTV strain 63140 in young birds shifts subsets of lymphocyte populations in the CALT and HG with minimal impact on the trachea.


Assuntos
Galinhas/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Galináceo 1/imunologia , Imunidade nas Mucosas , Doenças das Aves Domésticas/virologia , Animais , Túnica Conjuntiva/virologia , Feminino , Glândula de Harder/virologia , Cabeça/virologia , Infecções por Herpesviridae/virologia , Leucócitos/imunologia , Tecido Linfoide/virologia , Masculino , Organismos Livres de Patógenos Específicos , Vacinas Atenuadas/imunologia , Carga Viral/veterinária
3.
Parasitology ; 145(14): 1979-1989, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29806574

RESUMO

Behaviour manipulation imposed by parasites is a fascinating phenomenon but our understanding is still very limited. We studied the interaction between a virus and the parasitic wasp Leptopilina boulardi that attacks Drosophila larvae. Wasps usually refrain to lay eggs into already parasitized hosts (superparasitism avoidance). On the contrary, females infected by the Leptopilina boulardi Filamentous Virus (LbFV) are much more incline to superparasitize. Interestingly, the host-sharing induced by this behaviour modification leads to the horizontal transmission of the virus, thus increasing its fitness at the expense of that of the wasp. To better understand the mechanisms underlying this behaviour manipulation, we studied by RNA sequencing the meta-transcriptome of LbFV and the parasitic wasp both in the abdomen and in the head. We found that the abundance of viral transcripts was independent of the wasp strain but strongly differed between tissues. Based on the tissue pattern of expression, we identified a set of 20 viral genes putatively involved in the manipulation process. In addition, we identified a set of wasp genes deregulated in the presence of the virus either in the abdomen or in the head, including genes with annotations suggesting involvement in behaviour (i.e. Potassium-channel protein). This dataset gives new insights into the behaviour manipulation and on the genetic basis of superparasitism in parasitoids.


Assuntos
Comportamento Animal , Interações Hospedeiro-Parasita , Vírus de Insetos/genética , Transcriptoma , Vespas/genética , Abdome/virologia , Animais , Transmissão de Doença Infecciosa , Drosophila/parasitologia , Feminino , Cabeça/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Larva/parasitologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Vespas/virologia
4.
Euro Surveill ; 21(35)2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27605159

RESUMO

We report that two laboratory colonies of Culex quinquefasciatus and Culex pipiens mosquitoes were experimentally unable to transmit ZIKV either up to 21 days post an infectious blood meal or up to 14 days post intrathoracic inoculation. Infectious viral particles were detected in bodies, heads or saliva by a plaque forming unit assay on Vero cells. We therefore consider it unlikely that Culex mosquitoes are involved in the rapid spread of ZIKV.


Assuntos
Culex/virologia , Transmissão de Doença Infecciosa , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia , Zika virus/isolamento & purificação , Animais , Modelos Animais de Doenças , Cabeça/virologia , Insetos Vetores/virologia , Saliva/virologia , Glândulas Salivares/virologia , Fatores de Tempo , Células Vero/patologia , Carga Viral , Ensaio de Placa Viral
5.
Methods Mol Biol ; 1426: 119-28, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27233266

RESUMO

In vivo infection of mosquitoes is an important method to study and characterize arthropod-borne viruses. Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that is transmitted primarily by Aedes mosquitoes. In this chapter, we describe a protocol for infection of CHIKV in two species of Aedes mosquitoes, Aedes aegypti and Aedes albopictus, together with the isolation of CHIKV in different parts of the infected mosquito such as midgut, legs, wings, salivary gland, head, and saliva. This allows the study of viral infection, replication and dissemination within the mosquito vector.


Assuntos
Aedes/virologia , Infecções por Alphavirus/virologia , Vírus Chikungunya/patogenicidade , Animais , Vírus Chikungunya/isolamento & purificação , Vírus Chikungunya/fisiologia , Feminino , Cabeça/virologia , Humanos , Insetos Vetores/virologia , Intestinos/virologia , Extremidade Inferior/virologia , Saliva/virologia , Glândulas Salivares/virologia , Replicação Viral , Asas de Animais/virologia
6.
J Dent Res ; 94(11): 1532-43, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26353884

RESUMO

The human papillomavirus (HPV) is an etiologic agent associated with the development of head and neck squamous carcinoma (HNSCC)-in particular, oropharyngeal squamous cell carcinoma. The HPV-positive HNSCC is characterized by genetic alterations, clinical progression, and therapeutic response, which are distinct from HPV-negative head and neck cancers, suggesting that virus-associated tumors constitute a unique entity among head and neck cancers. Malignant stem cells, or cancer stem cells, are a subpopulation of tumor cells that self-renew, initiate new tumors upon transplantation, and are resistant to therapy, and their discovery has revealed novel effects of oncovirus infection in cancer. In this review, we provide a virus-centric view and novel insights into HPV-positive head and neck pathogenesis. We discuss the influence of cancer stem cells, HPV oncoproteins, altered molecular pathways, and mutations in cancer initiation and cancer progression. We compiled a catalogue of the mutations associated with HPV-positive HNSCC, which may be a useful resource for genomic-based studies aiming to develop personalized therapies. We also explain recent changes in mass vaccination campaigns against HPV and the potential long-term impact of vaccinations on the prevention and treatment of HPV-positive head and neck cancers.


Assuntos
Cabeça , Pescoço , Infecções por Papillomavirus/fisiopatologia , Células-Tronco/fisiologia , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/virologia , Dano ao DNA/fisiologia , Cabeça/virologia , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Pescoço/virologia , Células-Tronco Neoplásicas/fisiologia , Células-Tronco Neoplásicas/virologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico
7.
Parasit Vectors ; 7: 320, 2014 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-25015526

RESUMO

BACKGROUND: In Brazil, dengue epidemics erupt sporadically throughout the country and it is unclear if outbreaks may initiate a sustainable transmission cycle. There are few studies evaluating the ability of Brazilian Aedes aegypti populations to transmit dengue virus (DENV). The aim of this study was to compare DENV susceptibility of field-captured Ae. aegypti populations from nine distinct geographic areas of the city of Belo Horizonte in 2009 and 2011. Infection Rate (IR), Vector Competence (VC) and Disseminated Infection Rate (DIR) were determined. METHODS: Aedes aegypti eggs from each region were collected and reared separately in an insectary. Adult females were experimentally infected with DENV-2 and the virus was detected by qPCR in body and head samples. Data were analyzed with the Statistical Package for the Social Sciences version 17. RESULTS: IR varied from 40.0% to 82.5% in 2009 and 60.0% to 100.0% in 2011. VC ranged from 25.0% to 77.5% in 2009 and 25.0% to 80.0% in 2011. DIR oscillated from 68.7% to 100.0% in 2009 and 38.4% to 86.8 in 2011. When the results were evaluated by a logistic model using IR as covariate, North, Barreiro, South-Central and Venda Nova showed the strongest association in 2009. In 2011, a similar association was observed for South-Central, Venda Nova, West and Northeast regions. Using VC as covariate, South-Central and Venda Nova showed the most relevant association in 2009. In 2011, South-Central, Venda Nova and Barreiro presented the greatest revelation associations. When DIR data were analyzed by logistic regression models, Pampulha, South-Central, Venda Nova, West, Northeast and East (2009) as well as South-Central, Venda Nova and West (2011) were the districts showing the strongest associations. CONCLUSIONS: We conclude that Ae. aegypti populations from Belo Horizonte exhibit wide variation in vector competence to transmit dengue. Therefore, vector control strategies should be adapted to the available data for each region. Further analysis should be conducted to better understand the reasons for this large variability in vector competence and how these parameters correlate with epidemiological findings in subsequent years.


Assuntos
Aedes/fisiologia , Aedes/virologia , Vírus da Dengue/fisiologia , Dengue/epidemiologia , Insetos Vetores , Animais , Brasil/epidemiologia , Dengue/virologia , Doenças Endêmicas , Feminino , Cabeça/virologia , Glândulas Salivares/virologia
8.
Kulak Burun Bogaz Ihtis Derg ; 23(6): 341-3, 2013.
Artigo em Turco | MEDLINE | ID: mdl-24283809

RESUMO

A six-year-old girl was admitted to our clinic with the complaints of swelling, trismus, pain in the submandibular, submental and masticator area and vesicular lesions on the mandibular branch of trigeminal nerve (C5, V3). We present this case of head and neck space infection presenting with Herpes Simplex virus, as it is rarely seen.


Assuntos
Cabeça/virologia , Herpes Simples/diagnóstico , Pescoço/virologia , Criança , Diagnóstico Diferencial , Feminino , Herpes Simples/virologia , Humanos , Simplexvirus/isolamento & purificação , Nervo Trigêmeo/virologia
9.
PLoS Negl Trop Dis ; 7(3): e2013, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23505581

RESUMO

BACKGROUND: Aedes aegypti, is the major dengue vector and a worldwide public health threat combated basically by chemical insecticides. In this study, the vectorial competence of Ae. aegypti co-infected with a mildly virulent Metarhizium anisopliae and fed with blood infected with the DENV-2 virus, was examined. METHODOLOGY/PRINCIPAL FINDINGS: The study encompassed three bioassays (B). In B1 the median lethal time (LT50) of Ae. aegypti exposed to M. anisopliae was determined in four treatments: co-infected (CI), single-fungus infection (SF), single-virus infection (SV) and control (C). In B2, the mortality and viral infection rate in midgut and in head were registered in fifty females of CI and in SV. In B3, the same treatments as in B1 but with females separated individually were tested to evaluate the effect on fecundity and gonotrophic cycle length. Survival in CI and SF females was 70% shorter than the one of those in SV and control. Overall viral infection rate in CI and SV were 76 and 84% but the mortality at day six post-infection was 78% (54% infected) and 6% respectively. Survivors with virus in head at day seven post-infection were 12 and 64% in both CI and SV mosquitoes. Fecundity and gonotrophic cycle length were reduced in 52 and 40% in CI compared to the ones in control. CONCLUSION/SIGNIFICANCE: Fungus-induced mortality for the CI group was 78%. Of the survivors, 12% (6/50) could potentially transmit DENV-2, as opposed to 64% (32/50) of the SV group, meaning a 5-fold reduction in the number of infective mosquitoes. This is the first report on a fungus that reduces the vectorial capacity of Ae. aegypti infected with the DENV-2 virus.


Assuntos
Aedes/microbiologia , Aedes/virologia , Vírus da Dengue/isolamento & purificação , Insetos Vetores , Metarhizium/crescimento & desenvolvimento , Interações Microbianas , Aedes/fisiologia , Animais , Coinfecção , Feminino , Fertilidade , Trato Gastrointestinal/virologia , Cabeça/virologia , Humanos , Metarhizium/patogenicidade , Análise de Sobrevida
10.
BMJ Case Rep ; 20132013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23376665

RESUMO

Herpes simplex virus (HSV) is among a spectrum of viruses known to affect the upper aerodigestive tract. Gingivostomatitis and pharyngitis are the most common clinical manifestations of first-episode HSV infection, whereas recurrent herpes labialis is the most common clinical manifestation of reactivation HSV infection. Herpetic viral infections seldom attack the larynx. Laryngeal disorders provoked by the herpes virus are characterised by a large spectrum of presentations and polymorphisms, and can simulate mucous lesions such as an extensive laryngeal neoplasm (supraglottic tumour). We report a case of a 69-year-old woman, smoker, who presented with a large ulcerated supraglottic mass mimicking laryngeal cancer, requiring emergency tracheostomy for worsening stridor, which turned out to be an HSV laryngitis superimposed onto an underlying Streptococcus A lower respiratory tract infection. The patient was treated for Streptococcus A infection and her symptoms resolved following treatment. Patient's tracheotomy tube was removed on follow-up appointment.


Assuntos
Herpes Simples/patologia , Idoso , Feminino , Cabeça/diagnóstico por imagem , Cabeça/patologia , Cabeça/virologia , Herpes Simples/complicações , Herpes Simples/diagnóstico , Herpes Simples/diagnóstico por imagem , Humanos , Laringite/etiologia , Laringite/cirurgia , Laringite/virologia , Pescoço/patologia , Pescoço/virologia , Tomografia Computadorizada por Raios X , Traqueostomia
11.
J Gen Virol ; 94(Pt 3): 668-676, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23223622

RESUMO

The well-being of a colony and replenishment of the workers depends on a healthy queen. Diseases in queens are seldom reported, and our knowledge on viral infection in queens is limited. In this study, 86 honey bee queens were collected from beekeepers in Denmark. All queens were tested separately by two real-time PCRs: one for the presence of deformed wing virus (DWV), and one that would detect sequences of acute bee-paralysis virus, Kashmir bee virus and Israeli acute paralysis virus (AKI complex). Worker bees accompanying the queen were also analysed. The queens could be divided into three groups based on the level of infection in their head, thorax, ovary, intestines and spermatheca. Four queens exhibited egg-laying deficiency, but visually all queens appeared healthy. Viral infection was generally at a low level in terms of AKI copy numbers, with 134/430 tissues (31 %) showing the presence of viral infection ranging from 10(1) to 10(5) copies. For DWV, 361/340 tissues (84 %) showed presence of viral infection (DWV copies ranging from 10(2) to 10(12)), with 50 tissues showing viral titres >10(7) copies. For both AKI and DWV, the thorax was the most frequently infected tissue and the ovaries were the least frequently infected. Relative to total mass, the spermatheca showed significantly higher DWV titres than the other tissues. The ovaries had the lowest titre of DWV. No significant differences were found among tissues for AKI. A subsample of 14 queens yielded positive results for the presence of negative-sense RNA strands, thus demonstrating active virus replication in all tissues.


Assuntos
Abelhas/virologia , Vírus de Insetos/fisiologia , Animais , Feminino , Regulação Viral da Expressão Gênica/fisiologia , Cabeça/virologia , Interações Hospedeiro-Patógeno , Intestinos/virologia , Ovário/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real
12.
Virology ; 417(1): 106-12, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21652054

RESUMO

A country-wide screen for viral pathogens in Israeli apiaries revealed significant incidence of deformed wing virus (DWV) and Varroa destructor-1 virus (VDV-1). To understand these viruses' possible involvement in deformed wing syndrome of honey bees, we studied their replication in symptomatically and asymptomatically infected bees qualitatively and quantitatively, using RT-PCR, quantitative real-time RT-PCR, and immunodetection of the major viral capsid protein VP1. We found, for the first time, replication of VDV-1 and/or a VDV-1-DWV recombinant virus in the heads of recently emerged symptomatic bees. These viruses replicated to high copy numbers, yielding the major viral capsid VP1 processed for subsequent assembly of viral particles. Our results clearly distinguished between symptomatic and asymptomatic bees infected with VDV-1 and VDV-1-DWV and suggest the hypothesis that VDV-1, in addition to DWV, may be involved in inducing the deformed wing pathology. Thus VDV-1-DWV recombination may yield virulent strains able to cause overt infections in Varroa-infested bee colonies.


Assuntos
Abelhas/virologia , Vírus de RNA/genética , Vírus de RNA/fisiologia , Varroidae/virologia , Replicação Viral/fisiologia , Animais , Cabeça/virologia , Interações Hospedeiro-Patógeno , Vírus Reordenados
13.
J Dermatolog Treat ; 21(5): 311-3, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19895326

RESUMO

Human herpes simplex virus (HSV) infections are well-recognized complications of various dermatoses and have also been reported in both hereditary and acquired acantholytic diseases such as dyskeratosis follicularis (Darier's disease), familial benign chronic pemphigus (Hailey-Hailey disease) and pemphigus vulgaris, respectively. The possibility of HSV infection should be considered in pemphigus patients with lack of improvement under adequate immunosuppressive therapy. This has therapeutic implications, since antiviral treatment instantly clears the HSV-induced chronic erosions. Instead, augmentation or change of immune suppression for assumed refractory pemphigus will obviously not improve the condition. We suggest using the diagnostic term pemphigus herpeticatus to describe HSV-superinfected pemphigus, alluding to the pathophysiologic analogies with eczema herpeticatum.


Assuntos
Doença de Darier/diagnóstico , Herpes Simples/diagnóstico , Pênfigo Familiar Benigno/diagnóstico , Pênfigo/diagnóstico , Simplexvirus/isolamento & purificação , Adulto , Idoso , Antivirais/uso terapêutico , Doença de Darier/tratamento farmacológico , Doença de Darier/virologia , Diagnóstico Diferencial , Quimioterapia Combinada , Face/virologia , Cabeça/virologia , Herpes Simples/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pênfigo/tratamento farmacológico , Pênfigo/virologia , Pênfigo Familiar Benigno/tratamento farmacológico , Pênfigo Familiar Benigno/virologia , Tórax/virologia , Resultado do Tratamento
14.
J Infect Dis ; 200(12): 1901-6, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19919304

RESUMO

The distribution of the neurotropic alphaherpesviruses-herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) and varicella zoster virus (VZV)-was determined in autonomic and sensory ganglia of the head and neck obtained from formalin-fixed human cadavers. HSV-1 and VZV DNA were found in 18 of 58 and 16 of 58 trigeminal, 23 of 58 and 11 of 58 pterygopalatine, 25 of 60 and 14 of 60 ciliary, 25 of 48 and 11 of 48 geniculate, 15 of 50 and 8 of 50 otic, 14 of 47 and 4 of 47 submandibular, 18 of 58 and 10 of 58 superior cervical, and 12 of 36 and 1 of 36 nodose ganglia, respectively. HSV-2 was not detected at any site. Viral DNA positivity and location were independently distributed among autonomic and sensory ganglia of the human head and neck.


Assuntos
Gânglios/virologia , Cabeça/virologia , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 3/isolamento & purificação , Pescoço/virologia , Idoso , Idoso de 80 Anos ou mais , DNA Viral/isolamento & purificação , Feminino , Herpesvirus Humano 2/isolamento & purificação , Humanos , Masculino
15.
Vet Microbiol ; 138(1-2): 20-6, 2009 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-19264429

RESUMO

Roe deer papillomavirus (CcPV1) infection has been identified as an endemic disease in roe deer populations of the Carpathian basin in Central Europe (Hungary, Austria and Croatia). The disease is characterised by easily recognizable skin tumours similar to deer papillomavirus infection of North American deer species. In 2006, a questionnaire study was conducted among all Hungarian game management units (GMUs) in order to assess the distribution of the disease and its major epidemiological features. Categorical information was collected about disease occurrence, trend and frequency of detection, on primarily affected age classes in both sexes, and association of lesions with mortality. Replies were received from 539 GMUs representing 50.9% of total GMU territory and disease presence was reported by 295 (54.7%) GMUs. Older age classes of both sexes were found to be more affected. Association of various environmental factors with disease occurrence was evaluated and data were collected on the occurrence of similar skin lesions in other European countries. Pathological features of CcPV1 infection were described and the localisation of both CcPV1 antigen and DNA was characterised by immunohistochemistry and in situ DNA hybridisation in skin lesions. Virus presence was also demonstrated by PCR and PCR product sequencing.


Assuntos
Cervos/virologia , Infecções por Papillomavirus/veterinária , Animais , Antígenos Virais/análise , DNA Viral/genética , DNA Viral/isolamento & purificação , Europa (Continente)/epidemiologia , Cabeça/virologia , Membro Posterior/virologia , Humanos , Hungria/epidemiologia , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/mortalidade , Infecções por Papillomavirus/patologia , Reação em Cadeia da Polimerase , Estações do Ano , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/parasitologia , Neoplasias Cutâneas/veterinária , Neoplasias Cutâneas/virologia , Inquéritos e Questionários
16.
Infect Dis Clin North Am ; 21(2): 283-304, v, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17561072

RESUMO

A variety of methods, including direct examination of stained smears, antigen detection, routine and special cultures, and histopathologic evaluation are available for investigation of head and neck infections. Newer rapid molecular techniques with increased sensitivity and specificity are becoming available at many centers. Evaluation of specific causes in head and neck infections is complicated by the tendency for polymicrobial infections, difficulty in obtaining adequate specimens, and the presence of a diverse endogenous microflora at various mucosal sites that also can include true pathogens. These aspects of laboratory investigation for head and neck infections are reviewed in this article.


Assuntos
Cabeça/microbiologia , Cabeça/parasitologia , Infecções/etiologia , Pescoço/microbiologia , Pescoço/parasitologia , Infecções Bacterianas/microbiologia , Diagnóstico Diferencial , Cabeça/virologia , Humanos , Infecções/microbiologia , Infecções/parasitologia , Infecções/virologia , Pescoço/virologia
17.
J Gen Virol ; 86(Pt 12): 3419-3424, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16298989

RESUMO

Deformed wing virus (DWV) is a honeybee viral pathogen either persisting as an inapparent infection or resulting in wing deformity. The occurrence of deformity is associated with the transmission of DWV through Varroa destructor during pupal stages. Such infections with DWV add to the pathology of V. destructor and play a major role in colony collapse in the course of varroosis. Using a recently developed RT-PCR protocol for the detection of DWV, individual bees and mites originating from hives differing in Varroa infestation levels and the occurrence of crippled bees were analysed. It was found that 100 % of both crippled and asymptomatic bees were positive for DWV. However, a significant difference in the spatial distribution of DWV between asymptomatic and crippled bees could be demonstrated: when analysing head, thorax and abdomen of crippled bees, all body parts were always strongly positive for viral sequences. In contrast, for asymptomatic bees viral sequences could be detected in RNA extracted from the thorax and/or abdomen but never in RNA extracted from the head. DWV replication was demonstrated in almost all DWV-positive body parts of infected bees. Analysing individual mites for the presence of DWV revealed that the percentage of DWV-positive mites differed between mite populations. In addition, it was demonstrated that DWV was able to replicate in some but not all mites. Interestingly, virus replication in mites was correlated with wing deformity. DWV was also detected in the larval food, implicating that in addition to transmission by V. destructor DWV is also transmitted by feeding.


Assuntos
Abelhas/virologia , Vírus de Insetos/isolamento & purificação , Ácaros/virologia , Vírus de RNA/isolamento & purificação , RNA Viral/análise , Abdome/virologia , Animais , Cabeça/virologia , Vírus de Insetos/genética , Vírus de Insetos/fisiologia , Vírus de RNA/genética , Vírus de RNA/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tórax/virologia , Replicação Viral
18.
J Commun Dis ; 33(3): 174-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12206036

RESUMO

Distribution of West Nile (WN) virus antigen in different tissues of mosquitoes was studied in three species viz., Culex tritaeniorhynchus, C. vishnui and C. pseudovishnui. Overall per cent positivity was higher in the intra thoracically inoculated as compared to the orally infected mosquitoes, suggesting the existence of a midgut barrier. In a small number of mosquitoes salivary glands were found negative even though fluorescence was seen in the respective head squashes, suggesting salivary gland barrier in these mosquitoes. There was no difference in the per cent salivary gland and salivary gland area positivity between these three species. Presence of virus antigen in the ovaries of these three species on the 3rd post infection day suggests the possibility of transovarial transmission of virus even in the first gonotrophic cycle, which is of epidemiological importance.


Assuntos
Antígenos Virais/imunologia , Culex/virologia , Vírus do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Antígenos Virais/isolamento & purificação , Galinhas , Culex/classificação , Sistema Digestório/virologia , Feminino , Cabeça/virologia , Insetos Vetores/virologia , Camundongos , Ovário/virologia , Glândulas Salivares/virologia
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