Poxvirus infections in dermatology - the neglected, the notable, and the notorious.

The family Poxviridae currently comprises 22 genera that infect vertebrates. Of these, members of the Ortho-, Para-, Mollusci- and Yatapoxvirus genera have been associated with human diseases of high clinical relevance in dermatology. Historically, smallpox had been a notorious health threat until it was declared eradicated by the World Health Organization in 1979. Today, dermatologists are confronted with a variety of poxviral infections, such as farmyard pox, which occurs as a zoonotic infection after contact with animals. In the tropics, tanapox or vaccinia may be in the differential diagnosis as neglected tropical dermatoses. Molluscum contagiosum virus infection accounts for significant disease burden worldwide and is classified as a sexually transmitted infection in certain scenarios. Recently, mpox (monkeypox) has emerged as a public health emergency of international concern, requiring rapid recognition and appropriate management by dermatologists and infectious disease specialists. Advances and new insights into the epidemiology, diagnosis, clinical manifestations and complications, treatment, and prevention of poxviral infections require a high level of expertise and interdisciplinary skills from healthcare professionals linking virology, infectious diseases, and dermatology. This CME article provides a systematic overview and update to assist the practicing dermatologist in the identification, differential diagnosis, and management of poxviral infections.

Harnessing Attenuation-Related Mutations of Viral Genomes: Development of a Serological Assay to Differentiate between Capripoxvirus-Infected and -Vaccinated Animals.

Sheeppox, goatpox, and lumpy skin disease caused by the sheeppox virus (SPPV), goatpox virus (GTPV), and lumpy skin disease virus (LSDV), respectively, are diseases that affect millions of ruminants and many low-income households in endemic countries, leading to great economic losses for the ruminant industry. The three viruses are members of the Capripoxvirus genus of the Poxviridae family. Live attenuated vaccines remain the only efficient means for controlling capripox diseases. However, serological tools have not been available to differentiate infected from vaccinated animals (DIVA), though crucial for proper disease surveillance, control, and eradication efforts. We analysed the sequences of variola virus B22R homologue gene for SPPV, GTPV, and LSDV and observed significant differences between field and vaccine strains in all three capripoxvirus species, resulting in the truncation and absence of the B22R protein in major vaccines within each of the viral species. We selected and expressed a protein fragment present in wildtype viruses but absent in selected vaccine strains of all three species, taking advantage of these alterations in the B22R gene. An indirect ELISA (iELISA) developed using this protein fragment was evaluated on well-characterized sera from vaccinated, naturally and experimentally infected, and negative cattle and sheep. The developed wildtype-specific capripox DIVA iELISA showed >99% sensitivity and specificity for serum collected from animals infected with the wildtype virus. To the best of our knowledge, this is the first wildtype-specific, DIVA-capable iELISA for poxvirus diseases exploiting changes in nucleotide sequence alterations in vaccine strains.

Development and application of a real-time polymerase chain reaction assay to detect lumpy skin disease virus belonging to the Kenyan sheep and goat pox group.

Lumpy skin disease (LSD) outbreaks in Southeast and South Asia are attributed to different lineages of LSD virus (LSDV). Variants belonging to the novel recombinant cluster 2.5 circulate in China and Thailand, while a Kenyan sheep and goat pox (KSGP) strain from cluster 1.1 circulates in India, Pakistan, and Bangladesh. The clusters representing these circulating strains are vastly different. However, if their distribution encroaches into each other's ranges, it will be impossible to differentiate between them due to the lack of suitable molecular tools. Thus, fit-for-purpose molecular tools are in demand to effectively and timeously diagnose and investigate the epidemiology of LSDVs in a region. These could significantly contribute to the phylogenetic delineation of LSDVs and the development of preventive measures against transboundary spillovers. This work aimed to develop a real-time polymerase chain reaction assay targeting open reading frame LW032, capable of specifically detecting KSGP-related isolates and recombinant LSDV strains containing the KSGP backbone. The analytical specificity was proven against the widest possible panel of recombinant vaccine-like LSDV strains known to date. The amplification efficiency was 91.08%, and the assay repeatability had a cycle threshold variation of 0.56-1.1 over five repetitions across three runs. This KSGP-specific assay is reliable and fast and is recommended for use in LSDV epidemiological studies where the accurate detection of KSGP genetic signatures is a priority, particularly in regions where KSGP-like and other lineages are circulating.

Poxvirus Infections in Dairy Farms and Transhumance Cattle Herds in Nigeria.

Lumpy Skin disease (LSD) is an economically important disease in cattle caused by the LSD virus (LSDV) of the genus Capripoxvirus, while pseudocowpox (PCP) is a widely distributed zoonotic cattle disease caused by the PCP virus (PCPV) of the genus Parapoxvirus. Though both viral pox infections are reportedly present in Nigeria, similarities in their clinical presentation and limited access to laboratories often lead to misdiagnosis in the field. This study investigated suspected LSD outbreaks in organized and transhumance cattle herds in Nigeria in 2020. A total of 42 scab/skin biopsy samples were collected from 16 outbreaks of suspected LSD in five northern States of Nigeria. The samples were analyzed using a high-resolution multiplex melting (HRM) assay to differentiate poxviruses belonging to Orthopoxvirus, Capripoxvirus, and Parapoxvirus genera. LSDV was characterized using four gene segments, namely the RNA polymerase 30 kDa subunit (RPO30), G-protein-coupled receptor (GPCR), the extracellular enveloped virus (EEV) glycoprotein and CaPV homolog of the variola virus B22R. Likewise, the partial B2L gene of PCPV was also analyzed. Nineteen samples (45.2%) were positive according to the HRM assay for LSDV, and five (11.9%) were co-infected with LSDV and PCPV. The multiple sequence alignments of the GPCR, EEV, and B22R showed 100% similarity among the Nigerian LSDV samples, unlike the RPO30 phylogeny, which showed two clusters. Some of the Nigerian LSDVs clustered within LSDV SG II were with commonly circulating LSDV field isolates in Africa, the Middle East, and Europe, while the remaining Nigerian LSDVs produced a unique sub-group. The B2L sequences of Nigerian PCPVs were 100% identical and clustered within the PCPV group containing cattle/Reindeer isolates, close to PCPVs from Zambia and Botswana. The results show the diversity of Nigerian LSDV strains. This paper also reports the first documented co-infection of LSDV and PCPV in Nigeria.

Multiple accurate and sensitive arrays for Capripoxvirus (CaPV) differentiation.

Capripoxvirus (CaPV) contains three viruses that have caused massive losses in the livestock and dairy industries. Accurate CaPV differentiation has far-reaching implications for effectively controlling outbreaks. However, it has a great challenge to distinguishing three viruses due to high homology of 97%. Here, we established a sensitive CRISPR/Cas12a array based on Multiple-recombinase polymerase amplification (M-RPA) for CaPV differentiation, which provided a more comprehensive and accurate differentiation mode targeting VARV B22R and RPO30 genes. By sensitive CRISPR/Cas12a and M-RPA, the actual detection limits of three viruses were as low as 50, 40 and 60 copies, respectively. Moreover, Lateral flow dipstick (LFD) array based on CRISPR/Cas12a achieved portable and intuitive detection, making it suitable for point-of-care testing. Therefore, CRISPR/Cas12a array and LFD array paved the way for CaPV differentiation in practice. Additionally, we constructed a real-time quantitative PCR (qPCR) array to fill the qPCR technical gap in differentiation and to facilitate the quarantine departments.

Tanapox, South Africa, 2022.

Tanapox is a rarely diagnosed zoonosis known to be endemic to equatorial Africa. All previously reported human cases were acquired within 10° north or south of the Equator, most recently 19 years ago. We describe a human case of tanapox in South Africa (24° south of the Equator). Expanded surveillance for this pathogen is warranted.

Molecular epidemiology of swinepox viruses circulating in India.

Swinepox is a sporadic virus disease of domestic and wild pigs that mainly occurs during the rainy season. Though the disease is known for a century, research on swinepox especially genetic characterization is scanty. Self-limiting nature of the disease, the non-availability of specific diagnostics as well as the resemblance of clinical signs with other pathogens are some of the issues in the slow progress in swinepox-related research. Recent whole genome sequencing data from the USA, India, and Germany enhanced our understanding of the biology of swinepox virus (SWPV). The objective of the present study is to investigate the molecular epidemiology of two swinepox outbreaks that occurred in 2015 and 2016 one each in Uttar Pradesh, and the Haryana states of India. The appearance of clinical signs in different swine breeds was recorded. The scab samples from infected pigs were collected, DNA extracted, host range genes of SWPV were PCR amplified, sequenced and analyzed for genetic and phylogenetic characterization. Desi (nondescript breed), Yorkshire White pigs, and Landrace cross were found to be infected with SWPV. Host range genes of SWPV analyzed from clinical samples showed very high nucleotide identity with each other. Phylogenetic analyses revealed that SWPVs circulating in India are distinct (Indian lineage) from the SWPV of the USA, Germany, and Russia (European-North American lineage). Our study affirms the existence of two distinct lineages of SWPV globally with differences in clinical lesions between breeds.

Validation of molecular diagnostics for the detection of pseudocowpox virus.

The pseudocowpox virus (PCPV) is recognized for causing exanthematic lesions in cattle and humans. The diagnosis is important because it is a zoonosis and its clinical signs can be confused with foot-and-mouth disease, a high-impact bovine disease in livestock. The objective of this work is to validate a SYBR Green qPCR and a conventional PCR for virus detection in bovine samples. Detection limit tests, repeatability, reproducibility, sensitivity, and specificity were compared. When two analysts were compared, results demonstrated that training and pipetting influence the repeatability. The qPCR was more sensitive than conventional PCR but showed nonspecific reactions distinguishable by the melting curve. Both showed high repeatability and reproducibility.

Development of multiplex real-time PCR assays for differential detection of capripoxvirus, parapoxvirus and foot-and-mouth disease virus.

This study reports the development of multiplex real-time PCR assays for differential detection of capripoxvirus (CaPV), parapoxvirus (PaPV) and foot-and-mouth disease virus (FMDV) in sheep, goats and cattle. Three multiplex assays were developed, a capripox (CaP) rule-out assay for simultaneous detection and differentiation of CaPV and PaPV, a FMD rule-out assay for simultaneous detection and differentiation of FMDV and PaPV, and a FMD/CaP rule-out assay for simultaneous detection and differentiation of CaPV, PaPV and FMDV. All multiplex assays included ß-actin gene ACTB as an internal positive control to monitor PCR inhibition and accuracy of nucleic acid extractions. The optimized assays were highly specific to the target viruses (CaPV, PaPV and FMDV) with no cross-reactivity against other viruses that cause similar clinical signs. Using positive control plasmids as template, the limit of detection (LOD) of the multiplex assays were estimated as 2 CaPV, 7 PaPV and 15 FMDV copies per assay. The amplification efficiency (AE) and correlation coefficient (R2 ), estimated from the standard curves (Ct vs. log10 template dilution), were 94%-106% and >0.99, respectively, for CaP and FMD rule-out assays, 96%-116% (AE) and >0.98 (R2 ), respectively, for CaP/FMD rule-out assays and 91%-102% and >0.99, respectively, for the corresponding singleplex assays. The diagnostic sensitivity (DSe) of the multiplex assays was assessed on 35 CaPV and 39 FMDV clinical specimens from experimentally infected (CS-E) animals, and 29 CaPV (LSDV), 28 FMDV and 36 PaPV clinical specimens from naturally infected (CS-N) animals; all tested positive (DSe 100%) except two CS-E FMDV specimens that were tested negative by FMD rule-out and the corresponding singleplex (FMDV) assays (37/39; DSe 95%). The newly developed multiplex assays offer a valuable tool for differential detection of clinically indistinguishable CaPV, PaPV and FMDV in suspected animals and animals with mixed infections.

Retrospective study of poxviruses diagnosed in cattle from Goiás State, Brazil (2010-2018) / Estudo retrospectivo de poxviroses diagnosticadas em bovinos no estado de Goiás (2010-2018)

A retrospective study of poxvirus infections diagnosed in cattle from Goiás state (GO), Brazil, from 2010 to 2018, was performed. All cases have been investigated by the GO Official Veterinary Service (Agrodefesa), from which technical forms and protocols of veterinary diagnosis laboratories were reviewed. In most cases, samples of oral or cutaneous tissues and/or swabs were submitted for virological diagnosis by polymerase chain reaction (PCR) and/or virus isolation. Thirty seven outbreaks/cases of vesicular disease were notified in cattle of 25 counties; in 33 cases the animals presented lesions clinically compatible with poxviruses. The etiology of 25 out of 33 outbreaks/cases was confirmed as poxviruses by PCR and/or viral isolation: 13 as bovine vaccinia virus (VACV), six as pseudocowpox virus (PCPV), five as bovine papular stomatitis virus (BPSV) and one coinfection (VACV and an Orf virus-like parapoxvirus). The laboratory confirmed that cases occurred mainly in dairy cattle (19/25) and during the dry season (22/25). In adult cattle, gross changes were observed mainly in the teats and udder and included vesicles, ulcers, crusts, papules and scars and varied of type, severity and affected region, depending on the poxvirus species. In calves, the main lesions were ulcers in the mouth and muzzle. Zoonotic lesions compatible with poxvirus infections were observed for all diagnosed poxviruses, affecting especially the hands of milkers and other farm workers. Our data demonstrate the sanitary and economic relevance of these diseases and the wide circulation of different poxviruses in cattle from GO.(AU)

Foi realizado um estudo retrospectivo das infecções por poxvírus diagnosticadas em bovinos do estado de Goiás (GO), entre 2010 e 2018. Todos os casos foram investigados pela Agência Goiana de Defesa Agropecuária (Agrodefesa). Foram revisados formulários técnicos e protocolos de laboratórios de diagnóstico veterinário. Na maioria dos casos, amostras de tecidos orais ou cutâneos e/ou swabs foram encaminhadas para diagnóstico virológico. Foram notificados 37 surtos/casos de doença vesicular em bovinos em 25 municípios; em 33 casos os animais apresentavam lesões clinicamente compatíveis com poxvírus. A etiologia de 25 de 33 surtos/casos foi confirmada como poxvírus por PCR e/ou isolamento viral: 13 como vírus vaccínia (VACV), seis como vírus pseudocowpox (PCPV), cinco como vírus da estomatite papular bovina (BPSV) e um caso de coinfecção (VACV e um parapoxvírus semelhante ao Orf vírus). Os casos confirmados laboratorialmente ocorreram principalmente em bovinos leiteiros (19/25) e durante a estação seca (22/25). Em bovinos adultos, alterações macroscópicas foram observadas principalmente nas tetas e úbere e incluíram vesículas, úlceras, crostas, pápulas e cicatrizes e variaram quanto ao tipo, gravidade e região afetada, dependendo da espécie do poxvírus. Em bezerros, as principais lesões foram úlceras na boca e focinho. Lesões zoonóticas compatíveis com infecção por poxvírus foram observadas em todas as poxviroses diagnosticadas, afetando principalmente as mãos dos ordenhadores e outros trabalhadores rurais. Nossos dados demonstram a relevância sanitária e econômica dessas doenças e a ampla circulação de diferentes poxvírus em bovinos de GO.(AU)

Retrospective study of poxviruses diagnosed in cattle from Goiás State, Brazil (2010-2018) / Estudo retrospectivo de poxviroses diagnosticadas em bovinos no estado de Goiás (2010-2018)

A retrospective study of poxvirus infections diagnosed in cattle from Goiás state (GO), Brazil, from 2010 to 2018, was performed. All cases have been investigated by the GO Official Veterinary Service (Agrodefesa), from which technical forms and protocols of veterinary diagnosis laboratories were reviewed. In most cases, samples of oral or cutaneous tissues and/or swabs were submitted for virological diagnosis by polymerase chain reaction (PCR) and/or virus isolation. Thirty seven outbreaks/cases of vesicular disease were notified in cattle of 25 counties; in 33 cases the animals presented lesions clinically compatible with poxviruses. The etiology of 25 out of 33 outbreaks/cases was confirmed as poxviruses by PCR and/or viral isolation: 13 as bovine vaccinia virus (VACV), six as pseudocowpox virus (PCPV), five as bovine papular stomatitis virus (BPSV) and one coinfection (VACV and an Orf virus-like parapoxvirus). The laboratory confirmed that cases occurred mainly in dairy cattle (19/25) and during the dry season (22/25). In adult cattle, gross changes were observed mainly in the teats and udder and included vesicles, ulcers, crusts, papules and scars and varied of type, severity and affected region, depending on the poxvirus species. In calves, the main lesions were ulcers in the mouth and muzzle. Zoonotic lesions compatible with poxvirus infections were observed for all diagnosed poxviruses, affecting especially the hands of milkers and other farm workers. Our data demonstrate the sanitary and economic relevance of these diseases and the wide circulation of different poxviruses in cattle from GO.

Foi realizado um estudo retrospectivo das infecções por poxvírus diagnosticadas em bovinos do estado de Goiás (GO), entre 2010 e 2018. Todos os casos foram investigados pela Agência Goiana de Defesa Agropecuária (Agrodefesa). Foram revisados formulários técnicos e protocolos de laboratórios de diagnóstico veterinário. Na maioria dos casos, amostras de tecidos orais ou cutâneos e/ou swabs foram encaminhadas para diagnóstico virológico. Foram notificados 37 surtos/casos de doença vesicular em bovinos em 25 municípios; em 33 casos os animais apresentavam lesões clinicamente compatíveis com poxvírus. A etiologia de 25 de 33 surtos/casos foi confirmada como poxvírus por PCR e/ou isolamento viral: 13 como vírus vaccínia (VACV), seis como vírus pseudocowpox (PCPV), cinco como vírus da estomatite papular bovina (BPSV) e um caso de coinfecção (VACV e um parapoxvírus semelhante ao Orf vírus). Os casos confirmados laboratorialmente ocorreram principalmente em bovinos leiteiros (19/25) e durante a estação seca (22/25). Em bovinos adultos, alterações macroscópicas foram observadas principalmente nas tetas e úbere e incluíram vesículas, úlceras, crostas, pápulas e cicatrizes e variaram quanto ao tipo, gravidade e região afetada, dependendo da espécie do poxvírus. Em bezerros, as principais lesões foram úlceras na boca e focinho. Lesões zoonóticas compatíveis com infecção por poxvírus foram observadas em todas as poxviroses diagnosticadas, afetando principalmente as mãos dos ordenhadores e outros trabalhadores rurais. Nossos dados demonstram a relevância sanitária e econômica dessas doenças e a ampla circulação de diferentes poxvírus em bovinos de GO.

In vitro and in vivo analyses of co-infections with peste des petits ruminants and capripox vaccine strains.

BACKGROUND: Peste des petits ruminants (PPR) and goat pox (GTP) are two devastating animal epidemic diseases that affect small ruminants. Vaccination is one of the most important measures to prevent and control these two severe infectious diseases. METHODS: In this study, we vaccinated sheep with PPR and POX vaccines to compare the changes in the antibody levels between animals vaccinated with PPRV and POX vaccines alone and those co-infected with both vaccines simultaneously. The cell infection model was used to explore the interference mechanism between the vaccines in vitro. The antibody levels were detected with the commercial ELISA kit. The Real-time Quantitative PCR fluorescent quantitative PCR method was employed to detect the viral load changes and cytokines expression after the infection. RESULTS: The concurrent immunization of GTP and PPR vaccine enhanced the PPR vaccine's immune effect but inhibited the immune effect of the GTP vaccine. After the infection, GTP and PPR vaccine strains caused cytopathic effect; co-infection with GTP and PPR vaccine strains inhibited the replication of PPR vaccine strains; co-infection with GTP and PPR vaccine strains enhanced the replication of GTP vaccine strains. Moreover, virus mixed infection enhanced the mRNA expressions of TNF-α, IL-1ß, IL-6, IL-10, IFN-α, and IFN-ß by 2-170 times. GTP vaccine strains infection alone can enhanced the mRNA expression of IL-1ß, TNF-α, IL-6, IL-10, while the expression of IFN-α mRNA is inhibited. PPR vaccine strains alone can enhanced the mRNA expression of IFN-α, IFN-ß, TNF-α, and has little effect the mRNA expression of IL-1ß, IL-6 and IL-10. The results showed that GTP and PPR vaccine used simultaneously in sheep enhanced the PPR vaccine's immune effect but inhibited the immune effect of the GTP vaccine in vivo. Furthermore, an infection of GTP and PPR vaccine strains caused significant cell lesions in vitro; co-infection with GTP + PPR vaccine strains inhibited the replication of PPR vaccine strains, while the co-infection of GTP followed by PPR infection enhanced the replication of GTP vaccine strains. Moreover, virus infection enhanced the expressions of TNF-α, IL-1ß, IL-6, IL-10, IFN-α, and IFN-ß. CONCLUSIONS: Peste des petits ruminants and capripox vaccine strains interfere with each other in vivo and vitro.

Multiplex Real-Time PCR Method for Simultaneous Detection and Differentiation of Goat pox Virus, Sheeppox Virus, and Lumpy Skin Disease Virus.

BACKGROUND: The diseases caused by the Capripoxvirus species have very similar symptoms and are difficult to distinguish clinically. According to a recent report, Capripoxvirus are not strictly host specific. OBJECTIVE: This study aimed to identify the viruses from ovine (include sheep and goat) or bovine, which will assist in selecting the appropriate vaccine and correct measures to control diseases. METHOD: Universal primers for all Capripoxvirus and specific probes for lumpy skin disease virus, sheeppox virus, and goatpox virus were designed and analyzed to identify the viruses from ovine (including sheep and goats) or bovine species. The parameters of the system, such as the annealing temperatures and the quantities of primers and probes used, were optimized. The sensitivity, specificity, and reproducibility were tested. RESULTS: Each probe showed a specific fluorescent signal, with no cross reaction with other pathogens that cause symptoms similar to those of the poxviruses. The LOD was 102 copies of the target genome DNA. The 557 local clinical samples and samples from Ethiopia were successfully detected and the results were consistent with a restriction fragment length polymorphism PCR analysis of the P32 and RPO30 genes and gene sequencing. CONCLUSIONS: This optimized real-time PCR detection system has good diagnostic sensitivity and specificity and can be used for the rapid and effective differential diagnosis of these diseases in goats, sheep, and cattle. HIGHLIGHTS: It is a rapid detection method to distinguish the viruses from ovine (include sheep and goat) or bovine.

Molecular detection of myxoma virus in the environment of vaccinated rabbitries.

Myxoma virus (MYXV) is the aetiological agent of myxomatosis, a systemic, mostly lethal disease that affects European rabbits. Vaccination against it, although widespread, has not been completely effective and disease outbreaks still take place on farms which carry out vaccination programmes. Since some of these cases have been attributed to airborne transmission or the spread of the virus via inanimate vectors, the aims of this study were to determine MYXV contamination levels and distribution in the environment of vaccinated farms and to ascertain whether the detected virus corresponded to field strains. For that, environmental samples from several areas, tools and employees from four (three infected and one uninfected) rabbitries were taken and analysed by qPCR. MYXV was detected in the environment of all the infected farms, whereas all the samples from the non-infected farm were negative. Furthermore, all the positive samples contained viral DNA compatible with field strains of the virus. These results lead us to believe that the administration of currently available commercial vaccines does not prevent infected animals from shedding the field virus. Moreover, viral DNA was also found in items that are not in direct contact with the animals, which could play a role in the transmission of the infection throughout the farm and to other farms. Therefore, this study proves that current vaccination schemes on their own are not sufficient to prevent this disease and should be accompanied by adequate biosecurity measures.

Nódulos cutáneos múltiples en paciente embarazada / Multiple cutaneous nodules in a pregnant patient

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Identification of Clade E Avipoxvirus in Brazil.

Avian poxvirus (APV) is an enveloped double-stranded DNA virus that affects many domestic and wild birds worldwide. APVs are classified into three clades (A to C), represented by fowlpox (FP) virus (clade A), canarypox virus (clade B), and psittacinepox virus (clade C), although two additional clades (D and E) have been proposed. In this study, a tumorlike skin lesion found in a domestic fowl was submitted for molecular diagnosis of Avipoxvirus by PCR and sequencing. The phylogenetic analysis revealed that the amplified segment of the corelike 4b protein and polymerase genes clustered in clade E. The APVs in clade E were previously reported from outbreaks in Hungary (flock of turkeys) and in Mozambique (layer chickens), associated with a possible vaccine failure to protect against clade E viruses. To our knowledge, this report is the first identification of clade E in this country, providing new information about host range and genetic diversity of APVs in Brazil, and may represent a potential risk of FP disease outbreaks in commercial poultry.

Reporte de caso- Identificación del Avipoxvirus clado E en Brasil. El poxvirus aviar (APV) es un virus de ADN bicatenario envuelto que afecta a muchas aves domésticas y silvestres en todo el mundo. Los poxvirus aviares se clasifican en tres clados (A, B y C), representados por el virus de la viruela aviar (FP) (clado A), el virus de la viruela del canario (clado B) y el virus de la viruela de los psitácidos (clado C), aunque dos clados adicionales (D y E) han sido propuestos. En este estudio, una lesión cutánea similar a un tumor encontrada en una gallina doméstica fue sometida a diagnóstico molecular de Avipoxvirus por PCR y secuenciación. El análisis filogenético reveló que el segmento amplificado de los genes de la proteína del centro 4b y de la polimerasa se agruparon en el clado E. Los poxvirus aviares en el clado E se reportaron previamente de brotes en Hungría (parvada de pavos) y en Mozambique (gallinas de postura), asociados con una posible falla de la vacuna para proteger contra los virus del clado E. De acuerdo con el conocimiento de los autores, este informe es la primera identificación del clado E en este país, brindando nueva información sobre el rango de hospedadores y la diversidad genética de poxvirus aviares en Brasil, y puede representar un riesgo potencial de brotes de viruela aviar en aves comerciales.