AS CEPAS DE FILOVIRUS, O MEIO AMBIENTE E OS MORCEGOS DENTRO E FORA DA AFRICA.(Filovirus strains, the environment conditions and the Bats in and out of Africa).

Marburgvirus (MARV) e Ebolavirus (EBOV) pertencem à família Filoviridae. A infecção por MARV e EBOV pode causar uma devastadora febre hemorrágica em primatas. Os surtos de EBOV ocorreram nas florestas úmidas da África Central e Ocidental e MARV nas zonas mais secas e mais abertas da África Central e Oriental, também presentes no Sudeste Asiático e nas Filipinas. Nesta revisão, um paralelo da fauna de morcegos e condições climáticas em trópicos africanos onde a maioria dos focos de Filovírus ocorreu e as condições de ambientais brasileiros foram consideradas. Os morcegos de frutas da família Pteropodidae (Megachiroptera) que foram considerados um dos possíveis reservatórios dos vírus não estão representados na fauna brasileira. Do mesmo modo, não há representantes de Miniopterus schreibersiique foram associados ao vírus Lloviu e nenhum outro membro da subfamília Miniopterinae (família Vespertilionidae). Portanto, a infecção por suínos Ebolavirus do subtipo Reston (RESTV) e a possibilidade desses animais serem reservatórios naturais de vírus devem ser um alerta sobre a importância de medidas preventivas para evitar a entrada deste vírus no país.Abstract:Marburgvirus (MARV) and Ebolavirus (EBOV) belong to Filoviridae family. The MARV and EBOV infection can cause a devastating hemorrhagic fever in primates. The EBOV outbreaks occurred in the humid rain forests of central and western Africa and MARV in the drier and more open areas of central and eastern Africa also present in Southeast Asia and in the Philippines.  In this review, a parallel of the bat fauna and climate conditions in Afrotropics, where the most Filovirus outbreaks occurred, and Brazilian environments conditions were considered. The fruit bat from Pteropodidae family (Megabats) which were considered one of the possible reservoir species for the virus, are not represented in Brazilian fauna. In the similar way, there not representative of Miniopterus schreibersii bats which were associated with Lloviu virus neither other member of sub family Miniopterinae (Vespertilionidae family). Therefore, the swine infection of Ebolavirus sub type Reston (RESTV) and the possibility of pigs as natural virus reservoirs should be an alert about the importance of preventive measures to avoid the entrance of this virus in country

Implementação da técnica de imuno-histoquímica (IHQ) para o diagnóstico do circovírus suíno tipo-2 (CVS-2)

Porcine Circovirus Type 2 (PCV-2) is a non-enveloped circular single stranded DNA virus classified in the Circoviridae family, which is related to the development of post weaning multi systemic wasting syndrome (PMWS) in piglets. The PMWS is an emergent, multi-factorial illness of cosmopolitan distribution. PMWS clinical signals are unspecific and diagnosis involves also compatible findings of necropsy with identification of PMWS injuries must to be corroborated by demonstration of viral nucleic acid and/or antigen inside the lesions by hybridization “In Situ” (HIS) or of Immune-Histochemical (IHC) techniques, respectively. IHC technique allows the demonstration of viral antigen in situ using specific antibodies and antibody-conjugate. Implementation of IHC for PCV-2 diagnosis was carried out applying polyclonal antibody against PCV-2 in 23 blocks of histological sections, set with formalin-fixed and absorbed in paraffin filmstrip previously determined as positive or negative for the PCV-2. Previous histological analysis showed that positive tissues had characteristic PMWS lesions. HIS showed the presence of PCV-2 genome in tissue lesions. The implemented IHC was validated in 16 blocks containing three to four paraffin blocks, ranging of 48 to 64 tissue samples from swine with clinical suspicion of PMWS of which ten blocks (around 40 samples tissue samples) were confirmed by the analysis of virus genome. The results obtained by the IHC implementation demonstrated the presence of PCV-2 antigens in histological lesions compatible with the illness. IHC is successfully applied at PCV-2 surveys in swine from diverse Brazilian farms where is established the suspicion of PMWS occurrence.Circovírus Suíno Tipo-2 (CVS-2) é um virus não-envelopado, DNA fita única circular, classificado na família Circoviridae, associado à Síndrome Multissistêmica do Definhamento dos Suínos (SMDS). A SMDS é considerada uma doença emergente, multifatorial e de distribuição cosmopolita. Os sinais clínicos são inespecíficos e o diagnóstico, além dos achados de necropsia e histopatologia compatíveis com SMDS, deve ser corroborado pela demonstração do ácido nucléico e (ou) do antígeno viral nas lesões. A técnica de Imuno-Histoquímica (IHQ) permite a demonstração de antígenos virais pela aplicação de anticorpos específicos e conjugados de anticorpos. A implementação da IHQ foi realizada aplicando-se anticorpo policlonal anti – CVS -2 em 23 blocos de cortes histológicos, fixados com formalina e embebidos em parafina, sabidamente positivos ou negativos para o CVS-2. A análise histológica prévia demonstrou que os tecidos positivos continham lesões características da SMDS. O genoma do CVS-2 foi demonstrado pela Hibridização “in situ” (HIS). A IHQ implementada foi testada em 16 blocos com de três a quatro amostras de tecidos de animais, totalizando, respectivamente, 48 a 64 amostras de tecido de suínos com suspeita clínica da SMDS. Em dez blocos (40 amostras de tecidos) foram confirmadas pela detecção do genoma viral. Os resultados obtidos pela aplicação da IHQ padronizada foram correlacionados com as lesões histopatológicas compatíveis com a SMDS. A IHQ vem sendo aplicada com êxito no rastreamento do vírus em suídeos de diversas granjas brasileiras onde se estabelece a suspeita de ocorrência de SMDS

Epizootiology, laboratory and virulence analyses during the emergency phase of the African swine fever eradication program in Brazil in 1978: a historic account

 Após a ocorrência do primeiro surto de peste suína Africana (PSA) no Brasil, o laboratório oficial de diagnóstico de PSA (LDPSA) foi implantado. O trabalho atual revisa o esforço da equipe de laboratório para estabelecer o diagnóstico de PSA na fase emergencial do programa de erradicação. De Junho a Dezembro de 1978, 3803 amostras de tecido, sangue e soro de suínos foram analisadas. O primeiro isolamento do vírus da peste suína africana (VPSA) realizado pelo LDPSA foi feito em amostras de suínos oriundas da cidade de Teresópolis no Estado do Rio de Janeiro, Brasil. Em todo país, nos primeiros dois meses, de 320 amostras analisadas, 130 (40.62%) foram positivas pelo teste de hemadsorção o que sugere que a infecção com VPSA alcançou suínos em 96 dos 214 municípios analisados no período. A distribuição dos isolamentos do vírus no país mostrou uma possível rota de dispersão viral. Devido à rapidez das ações de eliminação dos focos, o número de amostras positivas caiu de 48,36% em Junho para 33,53% em Julho até nenhuma em Agosto, de 1978. Paralelamente, a detecção de anticorpos aumentou de 17,89% a 52,04% de Junho para Agosto de 1978. Os isolamentos do vírus pela técnica de hemadsorção (HAD) quando comparados com a descrição da doença e o forte declínio na taxa de mortalidade no Estado do Paraná sugeriram a ocorrência de cepas virais de VPSA de baixa a moderada virulência. A implantação do LDPSA foi crucial para o programa que assegurou a erradicação do VPSA em todo país após seis anos do primeiro surto. Os avanços na biologia celular e molecular corroboraram as suposições dos estudos pioneiros sobre a virulência viral e alertam para a importância de se estabelecer e manter medidas de segurança para prevenir a reintrodução do VPSA no país. A informação sobre heterogeneidade na virulência das populações virais nos surtos fornece uma ferramenta fundamental para a adoção de melhores medidas de erradicação.After the first African swine fever (ASF) outbreak occurred in Brazil in 1978, an official laboratory for ASF diagnosis (ASFDL) was established. The current work reviews the efforts of the laboratory team to define an ASF diagnosis during the emergency phase of the ASF Eradication Program. From June to December 1978, 3,803 samples of pig tissue, blood and serum were analyzed. ASFDL first isolated the ASF virus (ASFV) from pig tissue samples from the Teresópolis municipality in the Brazilian state of Rio de Janeiro. During the first two months, ASFV was isolated from 130 of 320 (40.62%) pig samples analyzed by haemadsorption (HAD), indicating that the outbreak had reached 96 of 214 municipalities surveyed throughout the country in that period. The distribution of positive ASFV samples indicated the potential route of virus dispersal. Because of the rapidity of the actions implemented against ASF, the number of ASFV positive samples decreased from 48.36% in June to 33.53% in July, and then to 0% in August 1978. In parallel, ASFV antibody detection increased from 17.89% in June to 52.04% in August 1978. In the state of Paraná, a comparison of ASFV isolates with descriptions of the disease, and a rapid decrease in mortality rates suggested the occurrence of a low or moderate virulence ASFV strain. Establishment of ASFDL was crucial for the program, which eradicated ASFV from the country within six years of the first outbreak. Advances in cellular and molecular biology corroborated pioneer studies regarding ASFV virulence, and have highlighted the importance of establishing and maintaining secure measures to prevent ASFV reintroduction to the country. Information on virulence heterogeneity in ASFV populations during outbreaks provided a paramount tool for the adoption of eradication best practices

Molecular studies on African swine fever virus from Brazilian isolates

ABSTRACT: African swine fever (ASF) is a devastating viral infirmity that affects domestic and wild swine caused by the ASF virus (ASFV) that belongs to the family Asfaviridae in the Asfavirus genus. Studies for genotypic and antigenic determination of ASFV including samples from Brazilian outbreaks were carried out outside Brazil. Here, we have reviewed studies on the molecular aspects of Brazilian isolates from 1978 and 1979. Results obtained from restriction fragment analysis, cloning and gene sequencing display the genotypic variation of viral samples. Viral genotyping based on sequences of the 3’ region of the p72 gene included in genotype I Brazilian samples, reinforcing the suggestion of the European origin for the virus that infected Brazilian herds and having low virulence potential. Corroborating those findings, at the American station PIADC, the infection of healthy pigs with the Brazilian strain induced ASF sub acute disease with low mortality and a low-virulence. Those results were similar with epidemiological vigilance forms of Brazilian swineherd in good health conditions having at least one ASFV isolation, and the ASF pioneer’s studies on the low mortality in the Brazilian herds affected by ASF. The ASFV spreading in Eastern Europe and Russia triggered a greater concern with intensifying the risk of viral dissemination from country to country. The low virulence ASF strains can increase the problem because of hidden viral reservoirs - which further reinforces the need for safety and preventive measures in virus-free countries. Finally, the problem is further compounded by the lack of vaccines and other immunological resources

Prostaglandin A1 Inhibits Replication of Classical Swine Fever Virus

Prostaglandins (Pgs) have been shown to inhibit the replication of several DNA and RNA viruses. Here we report the effect of prostaglandin (PgA1) on the multiplication of a positive strand RNA virus, Classical Swine Fever Virus (CSFV) in PK15 cells. PgA1 was found to inhibit the multiplication of CSFV. At a concentration of 5 g/ml, which was nontoxic to the cells, PgA1 inhibitis virus production in 99%. In PgA1 treated cells the size and number of characteristic Classical Swine Fever focus decreased in amount

Molecular studies on African swine fever virus from Brazilian isolates

<div><p>ABSTRACT: African swine fever (ASF) is a devastating viral infirmity that affects domestic and wild swine caused by the ASF virus (ASFV) that belongs to the family Asfaviridae in the Asfavirus genus. Studies for genotypic and antigenic determination of ASFV including samples from Brazilian outbreaks were carried out outside Brazil. Here, we have reviewed studies on the molecular aspects of Brazilian isolates from 1978 and 1979. Results obtained from restriction fragment analysis, cloning and gene sequencing display the genotypic variation of viral samples. Viral genotyping based on sequences of the 3’ region of the p72 gene included in genotype I Brazilian samples, reinforcing the suggestion of the European origin for the virus that infected Brazilian herds and having low virulence potential. Corroborating those findings, at the American station PIADC, the infection of healthy pigs with the Brazilian strain induced ASF sub acute disease with low mortality and a low-virulence. Those results were similar with epidemiological vigilance forms of Brazilian swineherd in good health conditions having at least one ASFV isolation, and the ASF pioneer’s studies on the low mortality in the Brazilian herds affected by ASF. The ASFV spreading in Eastern Europe and Russia triggered a greater concern with intensifying the risk of viral dissemination from country to country. The low virulence ASF strains can increase the problem because of hidden viral reservoirs - which further reinforces the need for safety and preventive measures in virus-free countries. Finally, the problem is further compounded by the lack of vaccines and other immunological resources.</p></div

Comparison of virological methods applied on african swine fever diagnosis in Brazil, 1978

ABSTRACT. Freitas T.R.P., Souza A.C., Esteves E.G. & Lyra T.M.P. [Comparison of virological methods applied on african swine fever diagnosis in Brazil, 1978.] Comparação dos métodos virológicos aplicados no diagnóstico da peste suína africana no Brasil, 1978. Revista Brasileira de Medicina Veterinária, 37(3):255-263, 2015. Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento, Avenida Rômulo Joviano, s/n, Caixa postal 35/50, Pedro Leopoldo, MG 33600-000, Brasil. [email protected] The techniques of leucocytes haemadsorption (HAD) for the African Swine Fever (ASF) virus isolation and the fluorescent antigens tissue samples (FATS) for virus antigens detection were implanted in the ASF eradication campaign in the country. The complementary of techniques was studied considering the results obtained when the HAD and FATS were concomitantly applied on the same pig tissue samples. The results of 22, 56 and 30 pigs samples from of the States of Rio de Janeiro (RJ), São Paulo (SP) and Paraná (PR), respectively, showed that in RJ 11 (50%); in SP, 28 (50%) and in PR, 15 (50%) samples were positive in the HAD, while, RJ, 18 (82%); SP, 33 (58%) and PR, 17 (57%) were positive in the FATS. In the universe of 108 samples submitted to both the tests, 83 (76.85%) were positive in at least one of the tests, which characterized ASF positivity. Among the positive samples, 28 (34%) have presented HAD negative results and 15 (18%) have presented FATS negative results. The achievement of applying simultaneously the both tests was the reduction of false- negative results, conferring more ASF accurate laboratorial diagnosis, besides to show the tests complementary. This aspect is fundamentally importance concern with a disease eradiation program to must avoid false negative results. Evidences of low virulence ASFV strains in Brazilian ASF outbreaks and also the distribution of ASF outbreaks by the mesoregions of each State were discussed. Public political action to avoid ASFV re-introduction should be thought and established. The successful experience of 1978 can be taken advantage for the country and for the outside

Research of antigen and antibodies against Porcine Circovirus Type - 2 in pigs with and without postweaning multsystemic wasting syndrome from commercial farms of Minas Gerais State<br>Pesquisa de antígenos e anticorpos contra Circovírus Suíno II em suínos com e sem sintomatologia da síndrome multisistêmica do definhamento em granjas comerciais mineiras

Porcine Circovirus Type 2 (PCV-2) is a non-enveloped circular single stranded DNA virus classified in the Circoviridae family related to post weaning multi systemic wasting syndrome (PMWS) in piglets. Immune-Histochemical (IHC) techniques are applied to detected PCV-2 antigen in the animal tissue injuries. Although, asymptomatic or sub clinic PCV-2 infected pigs could disseminate the virus in the flock. Serologic survey on apparently health pigs could suggest the virus ingression risk. In this work, antigens and antibodies against PCVS-2 in swine from commercial farms of seven and eight mesorregions of Minas Gerais State (MG) were investigated. 32 pigs with ages from five to eleven weeks which presented SMDS clinical signs were submitted to necropsy. PCV-2 antigens were investigated either from sacrificed pigs (Group I) and diagnosis demand samples (Group II) by IHC. 7,60% and more than 60% of the first and second groups, respectively, were positive for viral antigen. In both of them, intense marking of macrophages and histiocytes, especially in the lymph nodes and lung, evidenced antigens to CVS-2. In parallel, Immunoperoxidase Monolayer Assay (IPMA) was applied to antibody against PCV-2 screened in 955 pigs from 35 complete cycle commercial farms from same mesorregions. All pig flocks (100%) presented positive animals (confidence level 90% to 100%) and the frequency of reacting pigs varied 96.6% (confidence level 94,7% to 98,6%). PCV-2 antibody titers ranged 1:320 (medium) to 1:10.240 (high). The results suggest that 2.66% and 9% of pigs from Triângulo Mineiro and Zona da Mata regions respectively, would be able to develop clinical SMDS and that percentage reach 3.35% in the total serum.<p><p>Circovirus Suíno Tipo-2 (CSV-2) é um vírus não-envelopado, DNA fita única circular, classificado na família de Circoviridae, relacionado à Síndrome Multisistêmica do Definhamento de Suínos (SMDS) de leitões. A técnica de Imuno-Histoquímica (IHQ) é aplicada na detecção de antígenos do (CSV-2) em tecido lesionados. Entretanto, suínos infectados com CSV-2 assintomáticos ou com infecções subclínicas podem disseminar o vírus no plantel. A pesquisa de anticorpos contra o CVS-2 em porcos aparentemente saudáveis pode sugerir o risco de ingresso de vírus. Neste trabalho foram investigados antígenos e anticorpos contra CVS-2 de porcos de granjas comerciais de sete e oito mesorregiões de Estado de Gerais de Minas (MG). 32 porcos com idades de cinco a onze semanas que apresentaram sinais clínicos de SMDS foram necropsiados. Antígenos do CVS-2 foram investigados nos porcos sacrificados (grupo I) e amostras de demanda de diagnóstico (grupo II) pela IHQ. 7.60% e mais de 60%do primeiro e segundo grupo, respectivamente, foram positivos para antígeno viral. Em todos, marcação intense de macrófagos e histiócitos, especialmente nos linfonodos e pulmão, evidenciou antígenos a CVS-2. Em paralelo, 955 amostras de soros de porcos de 35 granjas comerciais de ciclo completo sem sintomatologia clínica de SMDS foram investigadas para a detecção de anticorpos contra o CVS-2 aplicando a técnica de Imunoperoxidase em Monocamada de Células (IPMC). Todos os rebanhos de suínos (100%) apresentaram animais positivos (nível de confiança 90% a 100%) com freqüência de 96,6% de porcos reagentes (nível de confiança 94.7% a 98,6%). Os títulos de anticorpos contra o CVS-2 variou 1:320 (médio) a 1:10.240 (alto). Os resultados sugerem que pelo menos 2,66% e 9% dos porcos das regiões Triângulo Mineiro e Zona da Mata, respectivamente, nesta amostragem poderiam desenvolver SMDS clínica e esta porcentagem alcança 3,35% no total dos soros