In vitro susceptibility of eighteen clinical isolates of human monkeypox virus to tecovirimat

BACKGROUND In 2022, an outbreak of mpox that started in European countries spread worldwide through human-to-human transmission. Cases have been mostly mild, but severe clinical presentations have been reported. In these cases, tecovirimat has been the drug of choice to treat patients with aggravated disease. OBJECTIVES Here we investigated the tecovirimat susceptibility of 18 clinical isolates of monkeypox virus (MPXV) obtained from different regions of Brazil. METHODS Different concentrations of tecovirimat were added to cell monolayers infected with each MPXV isolate. After 72 hours, cells were fixed and stained for plaque visualization, counting, and measurement. The ortholog of F13L gene from each MPXV isolate was polymerase chain reaction (PCR)-amplified, sequenced, and the predicted protein sequences were analyzed. FINDINGS The eighteen MPXV isolates generated plaques of different sizes. Although all isolates were highly sensitive to the drug, two showed different response curves and IC50 values. However, the target protein of tecovirimat, F13 (VP37), was 100% conserved in all MPXV isolates and therefore does not explain the difference in sensitivity. MAIN CONCLUSIONS Our results support screening different MPXV isolates for tecovirimat susceptibility as an important tool to better use of the restricted number of tecovirimat doses available in low-income countries to treat patients with mpox.

Viruela símica: zoonosis emergente con impacto global / Monkeypox: emerging zoonosis with unprecedentedglobal impact

El virus de la viruela símica es un orthopoxvirus de características zoonóticas endémico en las regiones de África Central y África Occidental, donde causa brotes desde 1970. En las últimas décadas se registró un aumento exponencial de casos, probablemente asociado a la disminución en la inmunidad conferida por la vacuna antivariólica, discontinuada luego de la erradicación de la viruela. En los últimos años se registraron casos esporádicos fuera del continente africano, siempre relacionados epidemiológicamente a la permanencia en áreas endémicas o contacto con animales infectados. Desde el 13 de mayo de 2022 se encuentra en curso el mayor brote de viruela símica registrado fuera de las áreas endémicas de África, con casos en los cinco continentes. La extensión, el impacto y la duración del brote permanecen aún inciertos.

Monkeypox virus is an orthopoxvirus with zoonotic characteristics endemic in Central and West Africa regions, where it has caused outbreaks since 1970. An exponential increase in cases has been registered in the last decades, probably associated with a decrease in the immunity conferred by the smallpox vaccine, discontinued after smallpox eradication. In recent years, sporadic cases have been reported outside the African continent, always epidemiologically related to permanence in endemic areas or contact with infected animals. Since May 13, 2022, the largest monkeypox outbreak ever reported outside Africa endemic areas, with cases on the five continents, is unfolding. The extent, impact and duration of this outbreak still remain uncertain

Molusco contagioso: actualización y casos clínicos / Molluscum contagiosum: an update and clinical cases

El molusco contagioso es una patología viral benigna muy frecuente, exclusiva del ser humano, y causada por un virus no clasificado del grupo de los Poxvirus. Las manifestaciones clínicas de la enfermedad inclu-yen lesiones en la piel, que pueden variar desde una pequeña pápula a un nódulo de mayor tamaño, pre-sentándose en forma solitaria o múltiple, dependien-do del estado inmunitario del paciente y del tiempo de evolución del proceso morboso. El estudio histo-patológico es importante para el diagnóstico, aunque en numerosas ocasiones éste se define clínicamen-te. Además del patrón histológico tradicional, y más frecuente, que exhibe hiperplasia e hipertrofia de la epidermis, se han descripto variantes poco usuales, cuyas características dependen, entre otros factores, de la sobreinfección y de la respuesta inmunitaria del paciente. En este trabajo se describen los rasgos ge-nerales del molusco contagioso y luego se presentan varios casos clínicos, uno de los cuales exhibe ma-nifestación inusual en la semimucosa del labio. Por último, se realizan comentarios referentes a la im-portancia que tiene para el odontólogo conocer esta patología y estar capacitado para detectarla, de modo de evitar sus complicaciones y su diseminación (AU)

Molluscum contagiosum is a very common benign viral pathologythat affects exclusively humans and is caused by an unclassified virus of the Poxvirus family. Clinical manifestations include skin lesions such as papule or nodule, which may range from a small papule to a larger nodule, presenting either solitary or multiple, depending on the immune status of the patient and the time of evolution of the morbid process. Histopathological study is important for the diagnosis, although in numerous occasions it is defined clinically. Classical and more frequent histology pattern exhibits hyperplasia and hypertrophy of the epidermis; however, distinct characteristics may occur depending on factors like superinfection and immune response of patients. This article describes general aspects of molluscum contagiosum and exposes several clinical cases, one of which exhibits an unusual manifestation in the semimucosa of the lip. Finally, comments are made regarding the importance for dentists to learn about the existence of this pathology and be able to recognize it in order to avoid its complications and spread (AU)

Tanapoxvirus: From discovery towards oncolytic immunovirotherapy

Insufficiency of standard cancer therapeutic agents and a high degree of toxicity associated with chemotherapy and radiotherapy have created a dearth of therapeutic options for metastatic cancers. Oncolytic viruses (OVs) are an emerging therapeutic option for the treatment of various human cancers. Several OVs, including poxviruses, are currently in preclinical and clinical studies and have shown to be effective in treating metastatic cancer types. Tanapoxvirus (TANV), a member of the Poxviridae family, is being developed as an OV for different human cancers due to its desirable safety and efficacy features. TANV causes a mild self-limiting febrile disease in humans, does not spread human to human, and its large genome makes it a relatively safer OV for use in humans. TANV is relatively well characterized at both molecular and clinical levels. Some of the TANV-encoded proteins that are a part of the virus' immune evasion strategy are also characterized. TANV replicates considerably slower than vaccinia virus. TANV has been shown to replicate in different human cancer cells in vitro and regresses human tumors in a nude mouse model. TANV is currently being developed as a therapeutic option for several human cancers including breast cancer, ovarian cancer, colorectal cancer, pancreatic cancer, retinoblastoma, and melanoma. This review provides a comprehensive summary from the discovery to the development of TANV as an OV candidate for a wide array of human cancers

Genomic diversity of vaccinia virus strain Cantagalo isolated in southeastern Brazil during the early years of the outbreak, 1999-2006

Outbreaks of a vesiculopustular disease in dairy cattle and milkers have been frequently reported in Brazil since 1999 when the vaccinia virus strain Cantagalo was first isolated in the State of Rio de Janeiro. However, the genomic diversity of the viral isolates associated with these outbreaks is not well known, particularly in the southeastern states that represent the focal point of virus spread to other regions. Here, we report the genomic sequences and an analysis of the polymorphic site profiles and genotypic diversity of four clinical isolates of vaccinia virus strain Cantagalo collected from 1999 to 2006 in southeastern Brazil.

New progress in medicinal chemistry of anti-poxvirus drugs research / 药学学报

Poxvirus is the largest and most complex virus of the known virions, and the main pathogenicity to humans is Orthopoxvirus. In recent years, with the deep understanding of the biological structure and replication cycle of Orthopoxvirus, new small molecular compounds with high efficiency and low toxicity have been discovered as new drugs, and some have entered the clinical trial stage. This article summarizes the research progress of poxvirus inhibitors with different targets.

Serological assay to detect human antibodies against monkey poxvirus / 中华实验和临床病毒学杂志

Objective@#To establish a method for detection of human antibodies against monkeypox virus.@*Mothds@#The enzyme linked immunosorbent assay (ELISA) plates were coasted with two monkeypox virus peptides from B21R protein, to establish an indirect ELISA for detecting monkeypox virus IgG antibody. The healthy individuals serum samples, monkeypox virus infected patient serum samples and other virus infected patient sera samples were applied to evaluate specificity of the peptides antigen. The reaction conditions were optimized.@*Results@#Synthesized two peptides from monkeypox virus BR21R protein did not cross react obviously with healthy person serum and other virus infected serum. It was shown that the reaction condition was best with sera dilution at 1∶50 when two combined peptides were coated at 100 ng /well, and second-antibody was diluted at 1∶20 000. At this condition the cut off value of IgG antibody in serum samples for ELISA were A450 reading of 0.393. The detected results of two serum samples collected from the monkeypox patient in Sierra Leone were strongly positive, the titers of IgG antibody in two sera were both 1∶6 400.@*Conclusions@#The indirect ELISA for detection of monkeypox virus infection was established preliminarily which provided useful tools for epidemiological study and diagnosis.

Outbreak of cutaneous form of avian poxvirus disease in previously pox-vaccinated commercial turkeys / Surto de bouba aviária na forma cutânea em perus comerciais previamente vacinados

This study describes an outbreak of avian poxvirus disease in previously pox-vaccinated turkeys in Brazil. The turkeys had suggestive gross lesions of cutaneous avian poxvirus in the skin of the head and cervical area without changes in the flock mortality rates. In the slaughterhouse, 30 carcasses were removed from the slaughter line to collect tissue from cutaneous lesions for histological analyses and characterization of the virus. The virus was identified by conventional polymerase chain reaction (PCR) and subsequent gene sequencing. Acanthosis, hyperkeratosis, and hydropic degeneration were seen on skin histopathology. Eosinophilic intracytoplasmic inclusion bodies (Bollinger) on keratinocytes were observed in 46.6% of the samples. Avian poxvirus DNA was detected on PCR in 83.3% of the total samples. PCR associated with histopathology had 93.3% of positivity for avian poxvirus. In the phylogenetic study, samples show 100% matching suggesting that the outbreak occurred by a single viral strain and was different from those strains affecting other wild birds such as canaries and sparrows. A single mutation (Adenine for Guanine) was detected in our study's strain and in the strains of turkey, chickens, and vaccine strains published in GenBank. Also, when the sequence strain of the present study and sequences from GenBank of canarypox and sparrowpox strains were aligned, a Thymine was found replacing the Adenine or Guanine. The in ovo vaccination method as single-use in turkeys of this study apparently did not provide adequate protection against avianpox disease, but additional vaccination administered by wing-web when turkeys were 45-60 days old in the new flocks controlled the disease. In the subsequent year, new cases of this disease were not found. It was not possible to confirm the source of the virus strain, but infection with a field strain derived from chickens is one possibility, considering the poultry farm population in the area and biosecurity aspects. For wide characterization of avipoxvirus and differentiation among strains, the complete sequence of the viral genome is required.(AU)

Este estudo descreve um surto de bouba aviária em perus previamente vacinados contra poxvirus aviário no Brasil. Os perus apresentaram lesões macroscópicas, sugestivas de bouba aviaria cutânea, na pele da cabeça e região cervical sem alteração nas taxas de mortalidade do lote. No abatedouro, 30 carcaças foram retiradas da linha de abate para coleta de dois fragmentos de pele com lesões para análise histológica e caracterização do vírus. A identificação do vírus foi realizada por PCR convencional e posterior sequenciamento. No exame histopatológico das lesões de pele, houve acantose, hiperqueratose e degeneração hidrópica. Corpúsculos de inclusão intracitoplasmáticos eosinofílicos (Bollinger) foram encontrados em 46,6% das amostras. A técnica de PCR detectou o DNA do vírus da bouba aviária em 83,3% do total de amostras. PCR associado com a histopatologia resultou em 93,3% de positividade para o vírus da bouba aviária. No estudo filogenético, as sequências resultaram em 100% de identidade, sugerindo que o surto ocorreu por uma única estirpe de vírus diferenciada das outras estirpes que acometem canários e pardais. Uma única mutação (Adenina para Guanina) foi detectada nas estirpes deste estudo e nas sequências de perus, galinhas e estirpes vacinais publicadas no GenBank. Além disso, quando a sequência da estirpe do presente estudo e as sequências das estirpes de canarypox e sparrowpox foram comparadas, a Timina foi encontrada em substituição a Adenina ou Guanina. A vacinação in ovo em dose única utilizada nos perus deste estudo aparentemente não forneceu proteção adequada contra a doença causada pelo poxvirus aviário. Entretanto, a revacinação na membrana da asa em perus com 45-60 dias de idade dos novos lotes controlou a doença. No ano subsequente, novos casos desta doença não foram registrados. Não foi possível confirmar a origem da estirpe viral, mas estirpes de campo oriundas de galinhas seria uma possibilidade, considerando a população na área e os aspectos de biosseguridade. Para caracterização ampla do avipoxvirus e diferenciação entre as estirpes, a sequência completa do genoma viral é requerida.(AU)

Swinepox dermatitis in backyard pigs in Northeastern Brazil / Varíola em suínos no Nordeste do Brasil

This article describes five outbreaks of swinepox in backyard pigs in Northeastern Brazil. It affected backyard pigs from herds of poor hygienic-sanitary conditions with severe fly and lice infestations. The morbidity ranged from 33.3 to 100% among affected herds, with mortality reaching up to 60%. The affected pigs developed multifocal to coalescent gray to white papules and blisters in the skin, with eventual eruptions, evolving to erosions and crusts. In addition to skin lesions, affected piglets presented apathy, anorexia and fever. The disease was auto-limiting, resolving within 15 to 25 days. Histological examination revealed proliferative and ulcerative vesiculopustular dermatitis with ballooning degeneration of epithelial cells, perivascular inflammatory infiltrates of lymphocytes, plasma cells, neutrophils, eosinophils and some macrophages in the dermis. Intracytoplasmic eosinophilic inclusions were consistently observed in keratinocytes. Total DNA extracted from fresh tissue fragments obtained from one outbreak and formalin-fixed, paraffin-embedded (FFPE) tissue from the other four outbreaks was submitted to polymerase chain reaction (PCR) for Swinepox virus (SWPV) and Vaccinia virus (VACV). Genetic SWPV material was identified by PCR in fresh material from one outbreak. Nucleotide sequencing and phylogenetic analysis of the PCR amplicons (viral polymerase gene) demonstrated 100% homology with sequences from SWPV. All tissues were PCR negative for VACV. Swine poxvirus is present in backyard pigs in Northeastern Brazil, indicating the need of including SWPV in the differential diagnosis of dermatitis in pigs.(AU)

Em cinco surtos de varíola em suínos no Nordeste do Brasil foram acometidos leitões e suínos adultos, de rebanhos domésticos criados em condições higiênico-sanitárias precárias, que apresentavam graves infestações por moscas e piolhos. A morbidade variou de 33,3-100% entre os rebanhos afetados e a mortalidade atingindo 60%. Os animais afetados desenvolveram pápulas cinzentas ou esbranquiçadas coalescentes e vesículas, que evoluíram para erosões e crostras. Além das lesões de pele, os leitões afetados apresentavam apatia, anorexia e febre. A doença foi autolimitante, com resolução em 15 a 25 dias. Histologicamente, observou-se dermatite proliferativa e ulcerativa com degeneração balonosa das células do epitélio, infiltrado inflamatório perivascular de linfócitos, plasmócitos, neutrófilos, eosinófilos e escassos macrófagos na derme. Inclusões eosinofílicas intracitoplasmáticas foram consistentemente observadas em queratinócitos. DNA total extraído a partir de fragmentos de tecido frescos obtidos a partir de um surto, e de tecido fixado em formol e embebido em parafina dos outros quatro surtos, foram submetidos à reação em cadeia da polimerase (PCR) para o vírus da varíola suína (SWPV) e o vírus vaccínia (VACV). Material genético do SWPV foi identificado por PCR em material fresco de um surto. O sequenciamento e análise filogenética dos produtos de amplificação da PCR (gene da polimerase viral) demonstraram 100% de homologia com sequências do SWPV. Todos os fragmentos de tecidos foram negativos para VACV na PCR. Este artigo relata a circulação de poxvírus suíno no Nordeste do Brasil, indicando a necessidade de incluir SWPV no diagnóstico diferencial de dermatite em suínos.(AU)

Pox viral infection in a rufous turtle dove

A dead dove was found on the road and submitted for diagnosis. The bird was severely emaciated, with deformation in its facial area. Grossly, white coalescing nodules were seen on the cut surface of the nasal cavity. Histopathologically, epithelial cells of the upper respiratory tract were markedly proliferated, with ballooning degeneration, down growth of the rete ridge, and large eosinophilic intracytoplasmic inclusion bodies. Parakeratotic hyperkeratosis and focal necrotic focus was present in the proliferative area. The facial bones showed partial bone resorption. Transmission electron microscopy revealed numerous viral particles in epithelial cells with dumbbell-shaped bodies, consistent with poxvirus.

Establishment and application of a fluorescence quantitative Taqman-PCR detection method of mouse poxvirus / 中国比较医学杂志

Objective To establish a fluorescence quantitative Taqman-PCR method for rapid and accurate detection of mouse poxvirus.Methods After sequence alignment and comparison, ERPV_027 gene was selected as the primer and probe design gene.Furthermore, the specificity, sensitivity, stability and reproducibility of these primers and probes were detected.Results The detection limitation of this method was 68 copies/μL.Data showed that this method has high specificity, which specifically amplifies mouse poxvirus, with no amplification signal of mouse hepatitis virus, Sendai virus, Salmonella and some other viruses and bacteria.This method also showed good stability and reproducibility. Conclusions This study has successfully established a fluorescence quantitative Taqman-PCR method for detection of mouse poxvirus, with high specificity, sensitivity, good stability and reproducibility, and a broad application potential.

Molusco contagioso exuberante em paciente HIV positivo / Molluscum contagiosum exuberant in HIV positive patient

O vírus do molusco contagioso (MCV) é um DNA vírus pertencente à família Poxviridae que apresenta quatro subtipos distintos, sendo o MCV1 mais prevalente e o MCV2 o mais frequente em adultos. As lesões são constituídas por pápulas firmes, umbilicadas, translúcidas medindo em média 5 mm, podendo haver lesões gigantes, encontradas no quadro da imunossupressão, principalmente na SIDA. Localizam-se preferencialmente no tronco, podendo ocorrer em qualquer parte da pele. É autoinoculável, inclusive após trauma. É doença tipicamente de crianças, porém pode ser considerada também uma doença transmissível por contato sexual. As lesões persistem por meses ou anos e acabam por desaparecer; podem involuir precocemente pela instalação de hipersensibilidade celular, o que se expressa clinicamente por eritema, descamação, infiltração e, por vezes, prurido...

Estudio clinico-epidemiologico de una serie de casos de pseudoviruela bovina (POXVIRUS) en humanos de la parroquia Espino, municipio Infante, estado Guárico, Venezuela

La pseudoviruela es una dermopatología maculopapular, pustulosa hasta ulcerativa, de curso autolimitado, causada por el virus ADN epiteliotropo, de la familia Poxviridae, género Parapoxvirus y especie Pseudocowpoxvirus, cuyos hospedadores son el ganado vacuno y el hombre; habitualmente se transmite a las personas por contacto con animales infectados. En la parroquia Espino Municipio Infante, Estado Guárico, se presento serie de casos en humanos a los cuales se realizó el estudio clínico-epidemiológico, previa confirmación por diagnóstico viral. Un total de dieciséis (16) casos fueron encuestados, bajo la modalidad de muestreo intencional, evidenciándose tendencia de acumulación de casos en menores de 34 años de edad (56,25%); el sexo masculino fue el más afectado (75.00%); según la ocupación 81.25% correspondió a ordeñadores y 87.50% de los declarantes, manifestaron no poseer ninguna experiencia anterior o estudios formales en el manejo de ganadería vacuna. Las lesiones tipo pápula, representan 75.00%, la región anatómica más afectada fue la mano (81.25%), generalmente con lesiones únicas. Se evidenció que las deficiencias en las prácticas preventivas de desinfección de la glándula mamaria, lavado de manos, uso de antisépticos, y uso de guantes por bioseguridad, son factores asociados a la frecuencia de aparición de casos. De allí que, para el control de la patología es imperativo, educar a los productores, ordeñadores y todos los trabajadores que tienen relación con la explotación de ganado bovino en prevención y control de enfermedades, normas de bioseguridad e higiene de la producción.

Investigation on Newcastle Disease Virus (NDV), Infectious Bursal Disease Virus (IBDV) and Avian Poxvirus (APV) in magellanic penguins in Southern region of Brazil

To investigate the exposure of the Newcastle disease virus (NDV), infectious bursal disease virus (IBDV) and avian poxvirus (APV) in Magellanic penguins found on the beaches in Southern regions of Brazil, the frequency of serum antibodies was estimated in 89 samples taken during 2005 and 2006. All the penguins were negative for the presence of antibodies against NDV by hemagglutination inhibition test and to APV by indirect ELISA. The reactivity was similar to the positives controls using ELISA kit for the IBDV made in the chickens in 50 samples. This reactivity also was demonstrated in 42 samples using agar gel immunodiffusion. No clinical signs related to IBDV infection were observed. The results indicated the absence of infection by NDV and APV but suggested IBDV exposure in the population of penguins studied.

Sequence Analysis of Attachment Gene of Lumpy Skin Disease and Sheep Poxviruses / 中国病毒学·英文版

In Egypt, protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy. In the present study 15 skin nodules from LSD suspected cows and 5 scab samples from sheep pox (SP) suspected sheep were collected. Hyperimmune rabbit sera to Lumpy skin disease virus (LSDV)/Ismailyia88 strain and sheep pox virus (SPV)/ Kenyan vaccinal strain were prepared. The causative agent in the collected samples was identified using immunoflourescence (IF) and immunoperoxidase techniques. Of the 15 skin nodules suspected of LSD, 10 showed a positive reaction and 3 out of 5 skin scabs suspected of sheeppox were found to be positive. An antigenic correlation between field skin isolate of LSDV, tissue culture adapted LSDV/Ismailyia88 strain, field skin isolate of SPV and SPV/Kenyan vaccinal strain was studied using prepared hyperimmune sera. Also, nucleotide sequence of the PCR amplified attachment gene fragments of field skin isolate of LSDV, tissue culture adapted LSDV/Ismailyia88 strain, field skin isolate of SPV and SPV /Kenyan vaccinal strain were compared. The results revealed that the four used viruses were antigenically identical. Sequence analysis indicated that field skin LSDV isolate is more related to tissue culture adapted LSDV/Ismailyia88 strain than to vaccinal SPV/ Kenyan strain and the skin isolate of SPV is more closely related to field skin isolate of LSDV than to SPV/Kenyan vaccinal strain. Thus, further study should be applied on the advantage of a LSD vaccine prepared from LSDV in protection of cattle against LSD compared to the commonly used sheep pox vaccine.

Ultrastructural study of poxvirus causing myxomatosis in rabbits, in São Paulo and Santa Catarina, Brazil / Estudio ultraestructural del poxvirus causal de mixomatosis en conejos, en São Paulo y Santa Catarina, Brasil

The myxomatosis is a contagious worldwide disease caused by poxvirus which infects domestic and wild rabbits. In the present study we present two distinct outbreaks of myxomatosis when raising rabbits, one for commercial purpose of production of meat and skins and, another one for the commercialization of ornamental rabbits. The observed signs were ocular, auricular, nasal, testis lesions and many times scattered throughout the body of the animals. The lesions were characterized by formation of nodules that by palpation disclosed gummy or gelatinous aspect. At the transmission electron microscopy, all the skin and crust samples were analyzed by negative staining technique. A great number of particles with morphology similar to the poxvirus, some enveloped in a brick-shaped and irregular disposition of tubules on the external membrane, measuring 300x240 nm on the average were visualized. Ultra thin sections revealed the presence of intracytoplasmic inclusion bodies surrounded by membrane containing oval particles, measuring 270 x 130 nm, containing nucleus or an internal biconcave (dumbbell-shaped) core. Immature particles (empty), surrounded by membrane were also observed. In addition, intracytoplasmic electron dense inclusion bodies containing viral particles budding of dense amorphous material and intranuclear fibrillar or "digital" inclusions showing a regular striation and arranged in groups were found in the middle of granular material. The nuclei were deformed with densely condensed chromatin forming amorphous and electron dense inclusion bodies. In the immunocytochemistry technique, the antigen-antibody reaction was strongly marked by the particles of colloidal gold, emphasizing the viral particles. The techniques used in this study were important in the diagnosis of the affected animals.

La mixomatosis es una enfermedad contagiosa de distribución mundial, causada por poxvirus que infecta conejos domésticos y salvajes. En este estudio presentamos dos distintos surtos por mixomatosis que ocurrieron en producciones de conejos, una para fines comerciales de producción de carne y pieles y otra para el comercio de conejos domésticos. Las señales observadas fueron afecciones oculares, nasales, testiculares y, a veces, también distribuida por todo el cuerpo de los animales. Estas se caracterizaban por formación de nódulos que a la palpación tenían un aspecto gelatinoso o gomoso. En la microscopía electrónica de transmisión, por la técnica de contrastación negativa, se pudo observar en todas las muestras examinadas de piel y de costras, un gran número de partículas típicas de poxvirus, con envoltura y forma de ladrillo, mostrando disposición irregular de los túbulos sobre la membrana externa, midiendo 300 x 240 nm en el promedio. Cortes ultrafinos de fragmentos de piel y de costras revelaron la presencia de cuerpos de inclusión intracitoplasmáticas, envueltos por membrana y conteniendo partículas ovales, midiendo 270 x 130 nm, conteniendo núcleo o centro interno bicóncavo (forma de mancuernas). Partículas inmaduras (vacías) envueltas por membrana fueron observadas. También fueron analizados cuerpos de inclusión intracitoplasmáticos, electrodensos, conteniendo partículas virales brotando del material denso y amorfo. Fueron observadas inclusiones intranucleares fibrilares o "digitales" mostrando una estriación periódica y disposición en grupos en medio del material granular. Los núcleos estaban deformados con cromatina densamente condensada formando cuerpos de inclusiones electrodensas y amorfas. En la técnica de imunocitoquímica la reacción antígeno-anticuerpo fue intensamente marcada por las partículas de oro coloidal realzando fuertemente las partículas virales.

Identification of poxvirus under transmission electron microscopy during outbreak period in wild birds, in São Paulo, Brazil / Identificación de poxvirus por microscopía electrónica de transmisión durante período de brote en aves silvestres en São Paulo, Brasil

Avianpox is a highly contagious disease infecting both commercial and wild birds, causing great damages to breeders and breeding. Caused by DNA viruses of the family Poxviridae, genus Avipoxvirus, if manifest through 3 forms, cutaneous, diphtheric and septicemic. In June 2003, during illegal commercialization of Brazilian birds, 800 wild birds (Paroaria dominicana, Sporophila caerulescens and Sporophila albogularis) were apprehended and being forwarded to the CRAS (Wild Animals Recovery Center), Tietê Ecological Park. After one month, birds presented cutaneous lesions in the beak and feet and anorexia, emaciation, locomotion difficulties, diarrhea, dehydration and death. Among the 800 birds, 500 died and 40 these (15 Paroaria dominicana, 15 Sporophila caerulescens and 10 Sporophila albogularis) were sent to the Electron Microscopy Laboratory of the Biology Institute of São Paulo, SP, to investigate viral agents. Scabs and fragments of skin lesions collected of theses birds were processed for transmission electron microscopy utilizing negative staining (rapid preparation), resin embedding and immunocitochemistry techniques. Under the transmission electron microscopy in all the analyzed samples it was visualized two types of poxvirus particles, M form, with regular spaced thread-like ridges comprising the exposed surface, measuring 280 x 230 nm; C form or stain-penetrated particle showing the dumbbell-shaped core surrounded by the outer envelope, measuring 360 x 330 nm. In the ultrathin sections obtained, three types of intracytoplasmic inclusion bodies were encountered: type A or Bollinger body, outlined by membrane, containing in its interior a great number of mature particles, measuring 200 x 300 nm, revealing the inner dumbbell-shaped core, two lateral bodies and an external envelope. In the type B electron dense inclusions bodies, viral particles budding of dense amorphous material were observed. Fibrillar inclusions constituted by ...

Avianpox es una enfermedad altamente contagiosa que infecta tanto aves comerciales como aves silvestres, causando grandes daños a lo ganadería y a la crianza. Causados por los virus de ADN de la familia Poxviridae, género Avipoxvirus, se manifiestan a través de 3 formas, cutánea, diftérica y septicémica. En junio del 2003, durante la comercialización ilegal de aves brasileñas, 800 aves silvestres (Paroaria dominicana; Sporophila caerulescens; Sporophila albogularis) fueron capturadas y remitidas al CRAS (Centro de Recuperación de Animales Silvestres), Parque Ecológico de Tietê. Después de un mes, las aves presentaron lesiones cutáneas en el pico y las patas, anorexia, adelgazamiento, dificultades de locomoción, diarrea, deshidratación y muerte. 500 de las 800 aves murieron, 40 de éstas (15 Paroaria dominicana, 15 Sporophila caerulescens y 10 Sporophila albogularis) fueron enviadas al Laboratorio de Microscopía Electrónica del Instituto de Biología de São Paulo, SP, para investigar agentes virales. Costras y fragmentos de lesiones en la piel de estas aves fueron recolectadas y se procesaron para microscopía electrónica de transmisión utilizando tinción negativa (preparación rápida), incrustación de resina y técnica inmunocitoquímica. Bajo la microscopía electrónica de transmisión en todas las muestras analizadas se encontraron dos tipos de partículas de poxvirus, Forma M, con espacios regulares como hilo que abarcan toda la superficie expuesta, midiendo 280 x 230 nm; Forma C o partícula teñida por penetración mostrando núcleo en forma de pesa rodeado por una envoltura externa, que medía 360 x 330 nm. Se encontraron en secciones ultrafinas, tres tipos de cuerpos de inclusión intracitoplásmica: el tipo A o cuerpo de Bollinger, esbozado por la membrana, que contiene en su interior un gran número de partículas maduras, que miden 200 x 300 nm, revelando núcleo interno en forma de pesa, dos cuerpos laterales y una envoltura externa. En el tipo ...