Recent progress and major gaps in the vaccine development for African swine fever.

The swine industry across the globe is recently facing a devastating situation imparted by a highly contagious and deadly viral disease, African swine fever. The disease is caused by a DNA virus, the African swine fever virus (ASFV) of the genus Asfivirus. ASFV affects both wild boars and domestic pigs resulting in an acute form of hemorrhagic fever. Since the first report in 1921, the disease remains endemic in some of the African countries. However, the recent occurrence of ASF outbreaks in Asia led to a fresh and formidable challenge to the global swine production industry. Culling of the infected animals along with the implementation of strict sanitary measures remains the only options to control this devastating disease. Efforts to develop an effective and safe vaccine against ASF began as early as in the mid-1960s. Different approaches have been employed for the development of effective ASF vaccines including inactivated vaccines, subunit vaccines, DNA vaccines, virus-vectored vaccines, and live attenuated vaccines (LAVs). Inactivated vaccines are a non-feasible strategy against ASF due to their inability to generate a complete cellular immune response. However genetically engineered vaccines, such as subunit vaccines, DNA vaccines, and virus vector vaccines, represent tailored approaches with minimal adverse effects and enhanced safety profiles. As per the available data, gene deleted LAVs appear to be the most potential vaccine candidates. Currently, a gene deleted LAV (ASFV-G-∆I177L), developed in Vietnam, stands as the sole commercially available vaccine against ASF. The major barrier to the goal of developing an effective vaccine is the critical gaps in the knowledge of ASFV biology and the immune response induced by ASFV infection. The precise contribution of various hosts, vectors, and environmental factors in the virus transmission must also be investigated in depth to unravel the disease epidemiology. In this review, we mainly focus on the recent progress in vaccine development against ASF and the major gaps associated with it.

Natural co-infection of pigs with African swine fever virus and porcine reproductive and respiratory syndrome virus in India.

Porcine reproductive and respiratory syndrome (PRRS) and African swine fever (ASF) are economically important diseases of pigs throughout the world. During an outbreak, all age groups of animals except piglets < 1 month of age were affected with symptoms of high fever, cutaneous hemorrhages, vomition with blood, diarrhea, poor appetite, ataxia, and death. The outbreak was confirmed by the detection of the N gene of the porcine reproductive and respiratory syndrome virus (PRRSV) and the VP72 gene of the African swine fever virus (ASFV) by PCR in representative blood samples from affected pigs followed by Sanger sequencing. Mixed infection was also confirmed by simultaneous detection of both the viruses using multiplex PCR. Phylogenetic analysis of both the viruses revealed that the outbreak was related to ASFV and PRRSV strains from China which were also closely related to the PRRSV and ASFV strains from the recent outbreak from India. The study confirmed the involvement of genotype II of ASFV and genotype 2 of PRRSV in the present outbreak. Interestingly, PRRSV associated with the present outbreak was characterized as a highly pathogenic PRRSV. Therefore, the present study indicates the possibility of future waves or further outbreaks of these diseases (PRRS and ASF) in this region. This is the first report of ASFV and PRRSV co-infection in pigs from India.

High-Risk Regions of African Swine Fever Infection in Mozambique.

African swine fever (ASF) is a transboundary infectious disease that can infect wild and domestic swine and requires enhanced surveillance between countries. In Mozambique, ASF has been reported across the country, spreading between provinces, mainly through the movement of pigs and their by-products. Subsequently, pigs from bordering countries were at risk of exposure. This study evaluated the spatiotemporal distribution and temporal trends of ASF in swine in Mozambique between 2000 and 2020. During this period, 28,624 cases of ASF were reported across three regions of the country. In total, the northern, central, and southern regions presented 64.9, 17.8, and 17.3% of the total cases, respectively. When analyzing the incidence risk (IR) of ASF per 100,000 pigs, the Cabo Delgado province had the highest IR (17,301.1), followed by the Maputo province (8868.6). In the space-time analysis, three clusters were formed in each region: (i) Cluster A involved the provinces of Cabo Delgado and Nampula (north), (ii) Cluster B involved the province of Maputo and the city of Maputo (south), and (iii) Cluster C consisted of the provinces of Manica and Sofala (central) in 2006. However, when analyzing the temporal trend in the provinces, most were found to be decreasing, except for Sofala, Inhambane, and Maputo, which had a stationary trend. To the best of our knowledge, this is the first study to evaluate the spatial distribution of ASF in Mozambique. These findings will contribute to increasing official ASF control programs by identifying high-risk areas and raising awareness of the importance of controlling the borders between provinces and countries to prevent their spread to other regions of the world.

Full genome sequence for the African swine fever virus outbreak in the Dominican Republic in 1980.

African swine fever is a lethal disease of domestic pigs, geographically expanding as a pandemic, that is affecting countries across Eurasia and severely damaging their swine production industry. After more than 40 years of being absent in the Western hemisphere, in 2020 ASF reappeared in the Dominican Republic and Haiti. The recent outbreak strain in the Dominican Republic has been identified as a genotype II ASFV a derivative of the ASF strain circulating in Asia and Europe. However, to date no full-length genome sequence from either the 1978-1980 Here we report the complete genome sequence of an African swine fever virus (ASFV) (DR-1980) that was previously isolated from blood collected in 1980 from the Dominican Republic at the end of the last outbreak, before culling of all swine on the island of Hispaniola and stored in the Plum Island Animal Disease Center ASFV repository. A contig representing the full-length genome (183,687 base pairs) was de novo assembled into a single contig using both Nanopore and Illumina sequences. DR-1980 was determined to belong to genotype I and, as determined by full genome comparison, a close relative to the sequenced Sardinia viruses that were causing outbreaks at this time.

An index for multidimensional assessment of swine health.

Pork accounts for almost one-third of the meat consumed worldwide. Infectious diseases have a marked impact on pig production. Epidemiological indicators are considered the most useful criteria in decision-making; however, a health status assessment remains a challenge at the national and regional levels. This study proposes a health index including herd-losses, morbidity, fatality, and type of diseases, to rate the health situation in a region or country; it contributes to assessing the effectiveness of control, damage manifestation, and trends. It is a multidimensional index with a structure of triads and simple quantitative, semi-quantitative, and qualitative expressions that use flexible and dynamics limits. With it, we analyzed twenty-one countries in 2005-2018, focusing on African swine fever, classical swine fever, foot-mouth-disease, and porcine respiratory and reproductive syndrome, diseases that caused 72% of the morbidity. Our multidimensional approach estimates farm, local, and regional impact from infectious agents and outbreaks, and apprises trends aiming to be useful to control measures, strategic actions, and animal health policies.

BOARD INVITED REVIEW: Prospects for improving management of animal disease introductions using disease-dynamic models.

Management and policy decisions are continually made to mitigate disease introductions in animal populations despite often limited surveillance data or knowledge of disease transmission processes. Science-based management is broadly recognized as leading to more effective decisions yet application of models to actively guide disease surveillance and mitigate risks remains limited. Disease-dynamic models are an efficient method of providing information for management decisions because of their ability to integrate and evaluate multiple, complex processes simultaneously while accounting for uncertainty common in animal diseases. Here we review disease introduction pathways and transmission processes crucial for informing disease management and models at the interface of domestic animals and wildlife. We describe how disease transmission models can improve disease management and present a conceptual framework for integrating disease models into the decision process using adaptive management principles. We apply our framework to a case study of African swine fever virus in wild and domestic swine to demonstrate how disease-dynamic models can improve mitigation of introduction risk. We also identify opportunities to improve the application of disease models to support decision-making to manage disease at the interface of domestic and wild animals. First, scientists must focus on objective-driven models providing practical predictions that are useful to those managing disease. In order for practical model predictions to be incorporated into disease management a recognition that modeling is a means to improve management and outcomes is important. This will be most successful when done in a cross-disciplinary environment that includes scientists and decision-makers representing wildlife and domestic animal health. Lastly, including economic principles of value-of-information and cost-benefit analysis in disease-dynamic models can facilitate more efficient management decisions and improve communication of model forecasts. Integration of disease-dynamic models into management and decision-making processes is expected to improve surveillance systems, risk mitigations, outbreak preparedness, and outbreak response activities.

Peste Suína Africana

A Peste Suína Africana (psa) é uma doença infecciosa de etiologia viral exclusiva da espécie suidea. Pode se apresentar tanto como um quadro superagudo como de uma forma clinicamente não aparente, com animais caracterizados como portadores sãos. A psa causa altíssimo prejuízo econômico, o vírus é resistente a amplas variações de pH e pode permanecer viável na pele por quase um ano. A psa teve sua origem no continente africano no início do século XX, e a partir das primeiras décadas do século XXI tem sido confirmada em países da Europa e da Ásia. Desde o ano de 2018 o rebanho suíno da China tem sido assolado pela psa, apresentando uma estimativa de redução do plantel situada entre 20 e 30%. No Brasil, o primeiro surto da psa ocorreu em 1978 quando foram registrados 223 focos da psa, contudo, em 1984 o país foi declarado livre da doença. Intensas ações de vigilância sanitária e epidemiológica são fundamentais para que a psa não volte a atingir a suinocultura brasileira.

Peste Suína Africana

A Peste Suína Africana (psa) é uma doença infecciosa de etiologia viral exclusiva da espécie suidea. Pode se apresentar tanto como um quadro superagudo como de uma forma clinicamente não aparente, com animais caracterizados como portadores sãos. A psa causa altíssimo prejuízo econômico, o vírus é resistente a amplas variações de pH e pode permanecer viável na pele por quase um ano. A psa teve sua origem no continente africano no início do século XX, e a partir das primeiras décadas do século XXI tem sido confirmada em países da Europa e da Ásia. Desde o ano de 2018 o rebanho suíno da China tem sido assolado pela psa, apresentando uma estimativa de redução do plantel situada entre 20 e 30%. No Brasil, o primeiro surto da psa ocorreu em 1978 quando foram registrados 223 focos da psa, contudo, em 1984 o país foi declarado livre da doença. Intensas ações de vigilância sanitária e epidemiológica são fundamentais para que a psa não volte a atingir a suinocultura brasileira.(AU)

Gaps in African swine fever: Analysis and priorities.

African swine fever (ASF) causes greater sanitary, social and economic impacts on swine herds than many other swine diseases. Although ASF was first described in 1921 and it has affected more than fifty countries in Africa, Europe and South America, several key issues about its pathogenesis, immune evasion and epidemiology remain uncertain. This article reviews the main characteristics of the causative virus, its molecular epidemiology, natural hosts, clinical features, epidemiology and control worldwide. It also identifies and prioritizes gaps in ASF from a horizontal point of view encompassing fields including molecular biology, epidemiology, prevention, diagnosis and vaccine development. The purpose of this review is to promote ASF research and enhance its control.

Epizootiology, laboratory and virulence analyses during the emergency phase of the African swine fever eradication program in Brazil in 1978: a historic account / Epizootiologia, análises laboratoriais e de virulência durante a fase emergencial do programa de erradicação da peste suína clássica no Brasil em 1978: um relato histórico

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...(AU)

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...(AU)

Phylogeographic analysis of African swine fever virus based on the p72 gene sequence.

African swine fever virus (ASFV) outbreak has been considered as an emerging and re-emerging disease for almost a century. Diagnostically, simple polymerase chain reaction and sequencing-based molecular detection could be employed for both viral identification and genotyping. This study established a novel phylogenetic analysis and epidemiology comparison based on 205 bp of p72 gene sequences. Based on this partial p72 fragment, an updated list of 44 different genotypes from a total of 516 ASFV sequences compiled from GenBank was generated. Nucleotide diversity was 0.04325 ± 0.00231. The analysis of spatial genetic variation divided the ASFV populations of the African continent into four clades (clade A: central and upper eastern Africa; clade B: eastern Africa; clade C: eastern and southern Africa; and clade D: southern Africa). These results and the developed protocol could serve as useful molecular tools for ASFV diagnosis from degraded DNA or putrefied samples, and also provide the phylogeographic perspective to identify the origin of viral outbreaks, facilitating the decision planning to limit their spread.

Epizootiology, laboratory and virulence analyses during the emergency phase of the African swine fever eradication program in Brazil in 1978: a historic account / Epizootiologia, análises laboratoriais e de virulência durante a fase emergencial do programa de erradicação da peste suína clássica no Brasil em 1978: um relato histórico

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...

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...

An analysis of the 1978 African swine fever outbreak in Brazil and its eradication.

The aim of this paper is to evaluate the African swine fever (ASF) outbreak that began in 1978 in Paracambi municipality, Rio de Janeiro State, Brazil, and the steps taken by the Brazilian authorities to eradicate the disease. The presence of ASF in the country was confirmed by isolating the virus, and its pathogenicity was certified by the laboratory of the Plum Island Disease Center, New York, United States. Even before the laboratory results became available, the Brazilian Agriculture Ministry declared an Animal Health Emergency, in which the official Veterinary Services adopted rapid control measures to restrain and eradicate the disease. These control measures contributed to the reorganisation of the national swine industry and stimulated the use of high-technology production techniques, as well as an improvement in herd health consciousness. All this contributed to Brazil becoming the largest meat exporter in the world.

Molecular epidemiology of African swine fever virus studied by analysis of four variable genome regions.

Variable regions of the African swine fever virus genome, which contain arrays of tandem repeats, were compared in the genomes of isolates obtained over a 40-year period. Comparison of the size of products generated by polymerase chain reaction (PCR) from four different genome regions, within the B602L and KP86R genes and intergenic regions J286L and BtSj, placed 43 closely related isolated from Europe, the Caribbean, West and Central Africa into 17 different virus sub-groups. Sequence analysis of the most variable fragment, within the B602L gene, from 81 different isolates distinguished 31 sub-groups of virus isolates which varied in sequence and number of a tandem repeat encoding 4 amino acids. Thus, each of these analysis methods enabled isolates, which were previously grouped together by sequencing of a more conserved genome region, to be separated into multiple sub-groups. This provided additional information about strains of viruses circulating in different countries. The methods could be used in future to study the epidemiology and evolution of virus isolates and to trace the sources of disease outbreaks.

[The eradication of African swine fever in Brazil, 1978-1984]. / La erradicación de la peste porcina africana en el Brasil, 1978-1984.

The African swine fever episode in Brazil was due to trade and tourism between Spain, Portugal and Brazil, at a time when outbreaks were on the rise in Europe. The eradication of the disease, the slaughter of pigs, the elimination of the carcasses and the isolation of affected farms were given wide media coverage, and had a major socio-economic impact. It was forbidden to raise pigs in garbage dumps or to give them feed considered hazardous. Analyses performed in Brazil as well as national and international investigations by researchers from reference laboratories concluded that the disease had spread from Rio de Janeiro to other states, as is stated in official reports. Following emergency measures, a control programme was implemented, leading to enhanced quality in the pig farming sector. The authors describe epidemiological surveillance of African swine fever, classical swine fever and related diseases, biosafety in swine farming, and the emergency action plan comprising animal health training for veterinarians and social workers. The results of the eradication programme were excellent, despite the controversy over compulsory sacrifice in a country with serious social problems. In 2004, Brazil was the fourth largest pork producer and exporter, with an output of 2.679 million tons and exports of 508,000 tons to international markets with very high standards.

Intra- and inter-genotypic size variation in the central variable region of the 9RL open reading frame of diverse African swine fever viruses.

African swine fever (ASF) viruses are characterised by numerous p72 genotypes, but by low levels of intra-genotypic variation, particularly in domestic pig associated genotypes. As it is precisely these viral lineages that are involved in outbreaks of the disease it is imperative that alternative, more informative gene regions be identified which are suitable for intra-genotypic resolution of relationships. To this end, the central variable region (CVR) of the 9RL open reading frame of diverse ASF viruses was amplified and product sizes scored and compared within and between genotypes. Results indicate that although product sizes are not genotype restricted, there is a high degree of intra-genotypic size variation particularly within the homogeneous p72 genotypes. Within one such genotype, the ESACWA virus genotype, 12 size-discrete CVR products were identified, four corresponding to viruses of west African origin and eight to viruses from countries where the disease is exotic, namely Europe, South America and the Caribbean. The high degree of size heterogeneity in the CVR of this genotype is significant and attests to the usefulness of the CVR gene marker in elucidating the epidemiology of African swine fever.

O surto de peste suína africana ocorrido em 1978 no município de Paracambi, Rio de Janeiro / The outbreak of African swine fever which ocurred in 1978 in the county of Paracambi, Rio de Janeiro, Brazil

Em função das dúvidas que ainda perduram 25 anos após a ocorrência do surto de peste suína africana (PSA), em Paracambi, Estado do Rio de Janeiro, Brasil, em 1978, são apresentados os resultados, relativos a este foco, obtidos pelos estudos epidemiológico, clínico-patológico, virológico, bacteriológico e ultra-estrutural dos casos naturais, bem como os relativos à reprodução experimental da doença no Brasil e sua confirmação por isolamento e determinação de patogenicidade realizada no Plum Island Animal Disease Center, New York, EUA. Os animais se infectaram pela ingestão de restos de comida de aviões procedentes de Portugal e da Espanha, países nos quais a doença existia. De acordo com publicação do Ministério da Agricultura, após o diagnóstico do surto de PSA descrito neste trabalho, 223 novos focos foram relatados, entre 1978 e 1979, em todas Regiões do país (Norte, Nordeste, Centro-Oeste, Sudeste e Sul) e focos adicionais em 1981, sem informações exatas referentes ao seu número. O último caso foi relatado em 15 de novembro de 1981, e em 5 de dezembro 1984 o Brasil foi declarado livre da PSA. Para o diagnóstico da PSA foram processadas 54.002 amostras no Departamento de Virologia do Instituto de Microbiologia da Universidade Federal do Rio de Janeiro, no período de 1978 a 1981. No processamento das amostras foram usadas as técnicas de hemadsorção em cultura de leucócitos (HAd), imunoflorescência em cortes de tecido (FATS), imunoflorescência em cultivo celular (FATCC), imuno-eletrosmoforese (IEOP) e imunoflorescência...(AU)

Due to doubts which still persist 25 years after the outbreak of African swine fever (ASF) which ocurred in the county of Paracambi, Rio de Janeiro, Brazil, in 1978, the results obtained through the studies to establish and confirm the diagnosis are presented. These include data on the epidemiology, clinic-pathological aspects, bacteriological, virological and ultramicroscopic examinations, the experimental reproduction of the disease and cross immunity tests with classical swine fever virus performed in Brazil, and on the confirmation with isolation of the virus and determination of its identity at the Plum Island Animal Disease Center, New York, USA. The pigs of the affected herd had been fed untreated remains of meals from airplanes of international lines flying to Brazil from Portugal and Spain where ASF was occurring at the time. According to publication by the Ministry of Agriculture, after the diagnosis of the outbreak of ASF described in this paper, 223 additional outbreaks were reported in Brazil between 1978 and 1979, in all the Brazilian regions (North, Northeast, Central-West, Southeast and South). Further outbreaks were reported in 1981, but their number is not known. The last case was reported to have occurred on November 15, 1981, and on December 5, 1984, Brazil was declared free of ASF. For the diagnosis of ASF 54,002 samples were examined by the Department of Virology of the Institute of Microbiology, Federal University of Rio de Janeiro, from 1978 to 1981, by the techniques of haemadsorption in leucocyte cultures (HAd), direct immunoflorescence in tissue sections (FATS), direct immunoflorescence in cell cultures (FATCC), immuno-electro-osmophoresis (IEOP) and indirect immunoflorescence assay (IIF). Only 4 samples were positive with the FATCC procedure. This is the only technique which includes virus isolation; the origin of these positive samples was not reported, but probably they were from the Paracambi outbreak... (AU)

O surto de peste suína africana ocorrido em 1978 no município de Paracambi, Rio de Janeiro / The outbreak of African swine fever which ocurred in 1978 in the county of Paracambi, Rio de Janeiro, Brazil

Em função das dúvidas que ainda perduram 25 anos após a ocorrência do surto de peste suína africana (PSA), em Paracambi, Estado do Rio de Janeiro, Brasil, em 1978, são apresentados os resultados, relativos a este foco, obtidos pelos estudos epidemiológico, clínico-patológico, virológico, bacteriológico e ultra-estrutural dos casos naturais, bem como os relativos à reprodução experimental da doença no Brasil e sua confirmação por isolamento e determinação de patogenicidade realizada no Plum Island Animal Disease Center, New York, EUA. Os animais se infectaram pela ingestão de restos de comida de aviões procedentes de Portugal e da Espanha, países nos quais a doença existia. De acordo com publicação do Ministério da Agricultura, após o diagnóstico do surto de PSA descrito neste trabalho, 223 novos focos foram relatados, entre 1978 e 1979, em todas Regiões do país (Norte, Nordeste, Centro-Oeste, Sudeste e Sul) e focos adicionais em 1981, sem informações exatas referentes ao seu número. O último caso foi relatado em 15 de novembro de 1981, e em 5 de dezembro 1984 o Brasil foi declarado livre da PSA. Para o diagnóstico da PSA foram processadas 54.002 amostras no Departamento de Virologia do Instituto de Microbiologia da Universidade Federal do Rio de Janeiro, no período de 1978 a 1981. No processamento das amostras foram usadas as técnicas de hemadsorção em cultura de leucócitos (HAd), imunoflorescência em cortes de tecido (FATS), imunoflorescência em cultivo celular (FATCC), imuno-eletrosmoforese (IEOP) e imunoflorescência...