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2.
Avian Pathol ; 49(4): 404-417, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32301627

RESUMEN

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.


Asunto(s)
Pollos/virología , Infecciones por Herpesviridae/veterinaria , Herpesvirus Gallináceo 1/inmunología , Inmunidad Mucosa , Enfermedades de las Aves de Corral/virología , Animales , Conjuntiva/virología , Femenino , Glándula de Harder/virología , Cabeza/virología , Infecciones por Herpesviridae/virología , Leucocitos/inmunología , Tejido Linfoide/virología , Masculino , Organismos Libres de Patógenos Específicos , Vacunas Atenuadas/inmunología , Carga Viral/veterinaria
3.
Parasitology ; 145(14): 1979-1989, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29806574

RESUMEN

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.


Asunto(s)
Conducta Animal , Interacciones Huésped-Parásitos , Virus de Insectos/genética , Transcriptoma , Avispas/genética , Abdomen/virología , Animales , Transmisión de Enfermedad Infecciosa , Drosophila/parasitología , Femenino , Cabeza/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Larva/parasitología , Canales de Potasio con Entrada de Voltaje/genética , Avispas/virología
4.
Euro Surveill ; 21(35)2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27605159

RESUMEN

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.


Asunto(s)
Culex/virología , Transmisión de Enfermedad Infecciosa , Infección por el Virus Zika/transmisión , Infección por el Virus Zika/virología , Virus Zika/aislamiento & purificación , Animales , Modelos Animales de Enfermedad , Cabeza/virología , Insectos Vectores/virología , Saliva/virología , Glándulas Salivales/virología , Factores de Tiempo , Células Vero/patología , Carga Viral , Ensayo de Placa Viral
5.
Methods Mol Biol ; 1426: 119-28, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27233266

RESUMEN

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.


Asunto(s)
Aedes/virología , Infecciones por Alphavirus/virología , Virus Chikungunya/patogenicidad , Animales , Virus Chikungunya/aislamiento & purificación , Virus Chikungunya/fisiología , Femenino , Cabeza/virología , Humanos , Insectos Vectores/virología , Intestinos/virología , Extremidad Inferior/virología , Saliva/virología , Glándulas Salivales/virología , Replicación Viral , Alas de Animales/virología
6.
J Dent Res ; 94(11): 1532-43, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26353884

RESUMEN

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.


Asunto(s)
Cabeza , Cuello , Infecciones por Papillomavirus/fisiopatología , Células Madre/fisiología , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/virología , Daño del ADN/fisiología , Cabeza/virología , Neoplasias de Cabeza y Cuello/etiología , Neoplasias de Cabeza y Cuello/virología , Humanos , Cuello/virología , Células Madre Neoplásicas/fisiología , Células Madre Neoplásicas/virología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico
7.
Parasit Vectors ; 7: 320, 2014 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-25015526

RESUMEN

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.


Asunto(s)
Aedes/fisiología , Aedes/virología , Virus del Dengue/fisiología , Dengue/epidemiología , Insectos Vectores , Animales , Brasil/epidemiología , Dengue/virología , Enfermedades Endémicas , Femenino , Cabeza/virología , Glándulas Salivales/virología
8.
Kulak Burun Bogaz Ihtis Derg ; 23(6): 341-3, 2013.
Artículo en Turco | MEDLINE | ID: mdl-24283809

RESUMEN

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.


Asunto(s)
Cabeza/virología , Herpes Simple/diagnóstico , Cuello/virología , Niño , Diagnóstico Diferencial , Femenino , Herpes Simple/virología , Humanos , Simplexvirus/aislamiento & purificación , Nervio Trigémino/virología
9.
PLoS Negl Trop Dis ; 7(3): e2013, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23505581

RESUMEN

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.


Asunto(s)
Aedes/microbiología , Aedes/virología , Virus del Dengue/aislamiento & purificación , Insectos Vectores , Metarhizium/crecimiento & desarrollo , Interacciones Microbianas , Aedes/fisiología , Animales , Coinfección , Femenino , Fertilidad , Tracto Gastrointestinal/virología , Cabeza/virología , Humanos , Metarhizium/patogenicidad , Análisis de Supervivencia
10.
BMJ Case Rep ; 20132013 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-23376665

RESUMEN

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.


Asunto(s)
Herpes Simple/patología , Anciano , Femenino , Cabeza/diagnóstico por imagen , Cabeza/patología , Cabeza/virología , Herpes Simple/complicaciones , Herpes Simple/diagnóstico , Herpes Simple/diagnóstico por imagen , Humanos , Laringitis/etiología , Laringitis/cirugía , Laringitis/virología , Cuello/patología , Cuello/virología , Tomografía Computarizada por Rayos X , Traqueostomía
11.
J Gen Virol ; 94(Pt 3): 668-676, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23223622

RESUMEN

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.


Asunto(s)
Abejas/virología , Virus de Insectos/fisiología , Animales , Femenino , Regulación Viral de la Expresión Génica/fisiología , Cabeza/virología , Interacciones Huésped-Patógeno , Intestinos/virología , Ovario/virología , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
12.
Virology ; 417(1): 106-12, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21652054

RESUMEN

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.


Asunto(s)
Abejas/virología , Virus ARN/genética , Virus ARN/fisiología , Varroidae/virología , Replicación Viral/fisiología , Animales , Cabeza/virología , Interacciones Huésped-Patógeno , Virus Reordenados
13.
J Dermatolog Treat ; 21(5): 311-3, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19895326

RESUMEN

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.


Asunto(s)
Enfermedad de Darier/diagnóstico , Herpes Simple/diagnóstico , Pénfigo Familiar Benigno/diagnóstico , Pénfigo/diagnóstico , Simplexvirus/aislamiento & purificación , Adulto , Anciano , Antivirales/uso terapéutico , Enfermedad de Darier/tratamiento farmacológico , Enfermedad de Darier/virología , Diagnóstico Diferencial , Quimioterapia Combinada , Cara/virología , Cabeza/virología , Herpes Simple/tratamiento farmacológico , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Pénfigo/tratamiento farmacológico , Pénfigo/virología , Pénfigo Familiar Benigno/tratamiento farmacológico , Pénfigo Familiar Benigno/virología , Tórax/virología , Resultado del Tratamiento
14.
J Infect Dis ; 200(12): 1901-6, 2009 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19919304

RESUMEN

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.


Asunto(s)
Ganglios/virología , Cabeza/virología , Herpesvirus Humano 1/aislamiento & purificación , Herpesvirus Humano 3/aislamiento & purificación , Cuello/virología , Anciano , Anciano de 80 o más Años , ADN Viral/aislamiento & purificación , Femenino , Herpesvirus Humano 2/aislamiento & purificación , Humanos , Masculino
15.
Vet Microbiol ; 138(1-2): 20-6, 2009 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-19264429

RESUMEN

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.


Asunto(s)
Ciervos/virología , Infecciones por Papillomavirus/veterinaria , Animales , Antígenos Virales/análisis , ADN Viral/genética , ADN Viral/aislamiento & purificación , Europa (Continente)/epidemiología , Cabeza/virología , Miembro Posterior/virología , Humanos , Hungría/epidemiología , Papillomaviridae , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/mortalidad , Infecciones por Papillomavirus/patología , Reacción en Cadena de la Polimerasa , Estaciones del Año , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/parasitología , Neoplasias Cutáneas/veterinaria , Neoplasias Cutáneas/virología , Encuestas y Cuestionarios
16.
Infect Dis Clin North Am ; 21(2): 283-304, v, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17561072

RESUMEN

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.


Asunto(s)
Cabeza/microbiología , Cabeza/parasitología , Infecciones/etiología , Cuello/microbiología , Cuello/parasitología , Infecciones Bacterianas/microbiología , Diagnóstico Diferencial , Cabeza/virología , Humanos , Infecciones/microbiología , Infecciones/parasitología , Infecciones/virología , Cuello/virología
17.
J Gen Virol ; 86(Pt 12): 3419-3424, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16298989

RESUMEN

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.


Asunto(s)
Abejas/virología , Virus de Insectos/aislamiento & purificación , Ácaros/virología , Virus ARN/aislamiento & purificación , ARN Viral/análisis , Abdomen/virología , Animales , Cabeza/virología , Virus de Insectos/genética , Virus de Insectos/fisiología , Virus ARN/genética , Virus ARN/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tórax/virología , Replicación Viral
18.
J Commun Dis ; 33(3): 174-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12206036

RESUMEN

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.


Asunto(s)
Antígenos Virales/inmunología , Culex/virología , Virus del Nilo Occidental/inmunología , Virus del Nilo Occidental/aislamiento & purificación , Animales , Antígenos Virales/aislamiento & purificación , Pollos , Culex/clasificación , Sistema Digestivo/virología , Femenino , Cabeza/virología , Insectos Vectores/virología , Ratones , Ovario/virología , Glándulas Salivales/virología
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