Impact of persistent bovine viral diarrhea virus infection on indicators of innate and adaptive immune function in holstein calves and cows / Impacto da infecção persistente pelo vírus da diarreia viral bovina sobre indicadoresde função imunológica inata e adaptativa em bezerras e vacas holandesas

ABSTRACT: We evaluated some indicators of innate and humoral immune response in persistently infected (PI) Holstein calves and cows from 1 to 36 months of age matched with controls from the same herd. The effects were cataloged by grouping animals into the following age groups: <12 months, 13 to 24 months, and 25 to 36 months of age. Blood samples were collected once from each animal to measure total serum protein, haptoglobin, and neutralizing antibodies titers induced by respiratory virus vaccination. Total serum protein (g/dL) was lowest in PI calves younger until 24 months old, while haptoglobin concentration was higher in PI cattle. The serum neutralizing titers against BVDV and BRSV were lower in all PI calves and cattle than in controls. PI cattle have a high serum concentration of haptoglobin, and its possible dysregulated innate immune response appears to impact the efficacy of their adaptative immune responses, resulting in poor vaccine responsiveness.

RESUMO: O objetivo desta pesquisa foi avaliar alguns indicadores da resposta imune inata e humoral em bezerros a vacas persistentemente infectadas, entre um a 36 meses de idade, pareados com controles oriundos de um mesmo rebanho. As variáveis respostas foram avaliadas agrupando-se os animais nos seguintes grupos etários: < 12 meses, 13 a 24 meses, 25 a 36 meses de idade. Amostras sanguíneas foram coletadas para mensurar as concentrações séricas de proteína, haptoglobina e anticorpos neutralizantes induzidos pela vacinação contra as viroses respiratórias. Os teores de proteína sérica total (g/dL) foram menores nos animais persistentemente infectados (PI) jovens até 24 meses de idade, enquanto que a concentração de haptoglobina foi maior nos animais PI mais velhos (25 a 36 meses). Os títulos de anticorpos neutralizantes contra o BVDV e BRSV foi menor nos animais PIs independentemente da idade, comparado com o grupo controle. Os valores reduzidos ou nulos de anticorpos contra as viroses respiratórias, combinado com a evidência de resposta imune inata desregulada, contribui com a susceptibilidade dos animais PIs para as infecções secundárias.

Impact of persistent bovine viral diarrhea virus infection on indicators of innate and adaptive immune function in holstein calves and cows / Impacto da infecção persistente pelo vírus da diarreia viral bovina sobre indicadores de função imunológica inata e adaptativa em bezerras e vacas holandesas

We evaluated some indicators of innate and humoral immune response in persistently infected (PI) Holstein calves and cows from 1 to 36 months of age matched with controls from the same herd. The effects were cataloged by grouping animals into the following age groups: <12 months, 13 to 24 months, and 25 to 36 months of age. Blood samples were collected once from each animal to measure total serum protein, haptoglobin, and neutralizing antibodies titers induced by respiratory virus vaccination. Total serum protein (g/dL) was lowest in PI calves younger until 24 months old, while haptoglobin concentration was higher in PI cattle. The serum neutralizing titers against BVDV and BRSV were lower in all PI calves and cattle than in controls. PI cattle have a high serum concentration of haptoglobin, and its possible dysregulated innate immune response appears to impact the efficacy of their adaptative immune responses, resulting in poor vaccine responsiveness.

O objetivo desta pesquisa foi avaliar alguns indicadores da resposta imune inata e humoral em bezerros a vacas persistentemente infectadas, entre um a 36 meses de idade, pareados com controles oriundos de um mesmo rebanho. As variáveis respostas foram avaliadas agrupando-se os animais nos seguintes grupos etários: < 12 meses, 13 a 24 meses, 25 a 36 meses de idade. Amostras sanguíneas foram coletadas para mensurar as concentrações séricas de proteína, haptoglobina e anticorpos neutralizantes induzidos pela vacinação contra as viroses respiratórias. Os teores de proteína sérica total (g/dL) foram menores nos animais persistentemente infectados (PI) jovens até 24 meses de idade, enquanto que a concentração de haptoglobina foi maior nos animais PI mais velhos (25 a 36 meses). Os títulos de anticorpos neutralizantes contra o BVDV e BRSV foi menor nos animais PIs independentemente da idade, comparado com o grupo controle. Os valores reduzidos ou nulos de anticorpos contra as viroses respiratórias, combinado com a evidência de resposta imune inata desregulada, contribui com a susceptibilidade dos animais PIs para as infecções secundárias.

Immunogenicity in sheep of Uruguayan commercial vaccines against bovine alphaherpesvirus 1, 5 and bovine pestiviruses / Imunogenicidade em ovelhas de vacinas comerciais Uruguaias para alfaherpesvírus bovino 1, 5 e pestivírus de bovinos

The serological responses induced by four commercial inactivated Uruguayan vaccines against bovine alphaherpesviruses (BoHV)-1 and -5 and bovine pestiviruses (BVDV-1, BVDV-2, and HoBiPeV) were evaluated in sheep. Thirty-seven sheep were immunized twice (day 0 and 25) and their serum samples were tested at different intervals (days 0, 25, 40, 60, and 90) post-vaccination (PV). Among the four vaccines tested, only one (G4) could induce the production of moderate neutralizing antibody titers against BoHV-1 and -5 and BVDV-1 and -2. The G3 vaccine showed a neutralizing serological response against the bovine alphaherpesviruses only. The G1 and G2 vaccines produced extremely low levels of antibodies in a few vaccinated animals only (geometric mean titers (GMT) 2.2). Similar levels of immunological responses were induced by the G4 vaccine against BoHV-1 and -5, and titers of neutralizing antibodies induced in approximately 70% of the animals are known to confer protection (GMT > 8). For bovine pestiviruses, the vaccine stimulated response of G4 against BVDV-2 was higher compared to that against BVDV-1, and extremely low for HoBiPeV. The peak of neutralizing antibodies to BoHV-1 and BVDV-1 was observed on days 40 and 60 PV, respectively. Thereafter, a remarkably decrease in neutralizing antibody response was observed at day 90 PV. These results demonstrated that tested commercial Uruguayan vaccines did not induce a serological response of adequate magnitude and duration. Thus, it is important to periodically review formulations and compositions of commercial vaccines against bovine alphaherpesviruses and pestiviruses.(AU)

A resposta sorológica induzida por quatro vacinas comerciais uruguaias inativadas contra os alfaherpesvírus bovinos (BoHV-1 e -5) e pestivírus de bovinos (BVDV-1, BVDV-2 e HoBiPeV) foi avaliada em ovinos. Os animais foram imunizados duas vezes (dia 0 e dia 25) e o soro testado em diferentes intervalos (dias 0, 25, 40, 60 e 90) após a vacinação (PV). Dentre as quatro vacinas testadas, apenas uma (G4) apresentou títulos de anticorpos neutralizantes moderados para os BoHV-1 e -5, BVDV-1 e 2. A vacina G3 apresentou resposta somente para alfaherpesvírus bovinos. As vacinas G1 e G2 estimularam resposta somente em alguns animais vacinados. Para a vacina G4, observou-se que a resposta imunológica frente ao BoHV-1 e 5 foi semelhante e pelo menos 70% dos animais apresentaram níveis protetivos de anticorpos neutralizantes. Para os pestivírus bovinos, a vacina G4 estimulou resposta para o BVDV-2 mais elevada quando comparada com o BVDV-1, e quase que indetectável para HoBiPeV. O pico de anticorpos neutralizantes para o BoHV-1 foi observado no dia 40 PV e no dia 60 PV para o BVDV-1. Após isso, observou-se um decréscimo considerável na resposta de anticorpos neutralizantes. Os resultados demonstraram que vacinas comerciais uruguaias testadas não induziram resposta sorológica de magnitude e duração adequadas. Assim, ressalva-se a importância de rever periodicamente a formulação e composição das vacinas comerciais para alfaherpesvírus e pestivírus bovinos.(AU)

Seroprevalence of bovine adenovirus and enterovirus antibodies reveals different infection dynamics in cattle herds

Background: Bovine enterovirus (BEV) and bovine adenovirus (BAV) are widely distributed in cattle population, and are among possible causes of gastroenteritis and respiratory disease, respectively, although the infection is more often subclinical. BAV infection may be also related to conjunctivitis, and may lead to severe infections and death in immunosuppressive calves. BEV infections have been associated with disorders of respiratory and reproductive tracts, and diarrhea. There is little available information about BAV and BEV in Brazil; however the main of the present study was to investigate the presence of antibodies against these viruses in cattle from some counties of the Rio Grande do Sul (RS), Brazil. Material, Methods & Results: A total of 415 bovine serum samples collected in 2015 year to detect neutralizing antibodies against BEV and BAV by Virus neutralization (VN) assay were performed. The serum samples were gently provided from Setor de Virologia da Universidade Federal de Santa Maria (SV-UFSM). The samples came from bovine with a history or report of clinical cases of diarrhea, respiratory and reproducible disorders and/or abortion suggestive of Leucosis, Bovine Viral Diarrhea Virus (BVDV) and/or Bovine herpesvirus type 1 and 5 (BoHV-1 and 5) infections. The samples are originated as from dairy and beef herd cattle in the following regions from RS State: Southwest, Northeast, Northwest, West, Southeast, Midwest and Metropolitan regions; and were classified according to the origin, gender and age. The serum samples were tested against 100 TCID50/mL of (tissue cellular infection dose 50/mL) of previously characterized BEV and BAV-3 isolates. Serial dilution of the serum was performed in duplicate, starting at 1:5 up to > 1:640 for BEV and at 1:2 to > 1:256 for BAV in 96 wells plates. The serum and virus mixture was incubated in 37ºC for 4-6 h and then a suspension of CRIB cells was added to each well. [...] (AU)

Seroprevalence of bovine adenovirus and enterovirus antibodies reveals different infection dynamics in cattle herds

Background: Bovine enterovirus (BEV) and bovine adenovirus (BAV) are widely distributed in cattle population, and are among possible causes of gastroenteritis and respiratory disease, respectively, although the infection is more often subclinical. BAV infection may be also related to conjunctivitis, and may lead to severe infections and death in immunosuppressive calves. BEV infections have been associated with disorders of respiratory and reproductive tracts, and diarrhea. There is little available information about BAV and BEV in Brazil; however the main of the present study was to investigate the presence of antibodies against these viruses in cattle from some counties of the Rio Grande do Sul (RS), Brazil. Material, Methods & Results: A total of 415 bovine serum samples collected in 2015 year to detect neutralizing antibodies against BEV and BAV by Virus neutralization (VN) assay were performed. The serum samples were gently provided from Setor de Virologia da Universidade Federal de Santa Maria (SV-UFSM). The samples came from bovine with a history or report of clinical cases of diarrhea, respiratory and reproducible disorders and/or abortion suggestive of Leucosis, Bovine Viral Diarrhea Virus (BVDV) and/or Bovine herpesvirus type 1 and 5 (BoHV-1 and 5) infections. The samples are originated as from dairy and beef herd cattle in the following regions from RS State: Southwest, Northeast, Northwest, West, Southeast, Midwest and Metropolitan regions; and were classified according to the origin, gender and age. The serum samples were tested against 100 TCID50/mL of (tissue cellular infection dose 50/mL) of previously characterized BEV and BAV-3 isolates. Serial dilution of the serum was performed in duplicate, starting at 1:5 up to > 1:640 for BEV and at 1:2 to > 1:256 for BAV in 96 wells plates. The serum and virus mixture was incubated in 37ºC for 4-6 h and then a suspension of CRIB cells was added to each well. [...]

Seroprevalence of Bovine Adenovirus and Enterovirus Antibodies Reveals Different Infection Dynamics in Cattle Herds

Background: Bovine enterovirus (BEV) and bovine adenovirus (BAV) are widely distributed in cattle population, and are among possible causes of gastroenteritis and respiratory disease, respectively, although the infection is more often subclinical. BAV infection may be also related to conjunctivitis, and may lead to severe infections and death in immunosuppressive calves. BEV infections have been associated with disorders of respiratory and reproductive tracts, and diarrhea. There is little available information about BAV and BEV in Brazil; however the main of the present study was to investigate the presence of antibodies against these viruses in cattle from some counties of the Rio Grande do Sul (RS), Brazil.Material, Methods & Results: A total of 415 bovine serum samples collected in 2015 year to detect neutralizing antibodies against BEV and BAV by Virus neutralization (VN) assay were performed. The serum samples were gently provided from Setor de Virologia da Universidade Federal de Santa Maria (SV-UFSM). The samples came from bovine with a history or report of clinical cases of diarrhea, respiratory and reproducible disorders and/or abortion suggestive of Leucosis, Bovine Viral Diarrhea Virus (BVDV) and/or Bovine herpesvirus type 1 and 5 (BoHV-1 and 5) infections. The samples are originated as from dairy and beef herd cattle in the following regions from RS State: Sout

Serological response to rabies virus induced by commercial vaccines in cattle / Resposta sorológica ao vírus da raiva induzida por vacinas comerciais em bovinos

The antibody response to rabies virus (RABV) induced by commercial vaccines in heifers was investigated. For this, 84 heifers were vaccinated twice (30 days interval) with each of four vaccines (G1 = 14 animals; G2 = 24; G3 = 22 and G4 = 24) and received a booster vaccination 360 days later. Serum samples collected at different intervals after vaccination and 30 days after booster were submitted to a virus neutralizing (VN) assay for RABV antibodies. Thirty days after the second vaccine dose, 92% of the immunized animals presented VN titers 0.5UI/mL (geometric medium titers [GMT] 1.7 to 3.8UI/mL). At the day of the booster (360 days post-vaccination); however, the percentage of animals harboring antibody titers 0.5UI/mL had dropped to 31% (0-80% of the animals, depending on the vaccine), resulting in lower GMT (0.1 to 0.6UI/mL). Booster vaccination at day 360 resulted in a detectable anamnestic response in all groups, resulting in 83% of animals (65 to 100%) harboring VN titers 0.5UI/mL thirty days later (GMT 0.6 to 4.3UI/mL). These results indicated that these vaccines were able to induce an adequate anti-RABV response in all animals after prime vaccination (and after booster as well). However, the titers decreased, reaching titers 0.5UI/mL in approximately 70% of animals within the interval before the recommended booster. Thus, booster vaccination for rabies in cattle using the current vaccines should be performed before the recommended one-year interval, as to maintain neutralizing antibodies levels in most vaccinated animals.

A resposta sorológica contra o vírus da raiva (RABV) induzida por vacinas comerciais foi investigada em bovinos. Para isso, 84 novilhas foram vacinadas duas vezes (30 dias de intervalo) com cada vacina (G1 = 14 animais; G2 = 24; G3 = 22 e G4 = 24) e receberam uma vacinação de reforço 360 dias depois. Amostras de soro coletadas em diferentes momentos após a vacinação e após o reforço vacinal foram submetidas ao teste de vírus neutralização (VN) para detecção de anticorpos contra o RABV. Trinta dias após a segunda dose vacinal, 92% dos animais apresentaram títulos neutralizantes 0,5UI/mL (GMT 1,7 a 3,8UI/mL). Porém, no dia do reforço (360 dias pós-vacinação), a porcentagem de animais que ainda apresentava títulos 0,5UI/mL havia se reduzido a 31% dos animais (0 a 80%, dependendo da vacina), resultando em baixos TMGs (0,1 a 0,6UI/mL). A vacinação de reforço no dia 360 resultou em resposta anamnéstica em todos os grupos, resultando em 83% (65 a 100%) de animais com títulos VN 0,5UI/mL trinta dias após (GMT 0,6 a 4,3UI mL-1). Esses resultados indicam que as vacinas avaliadas induzem uma resposta adequada de anticorpos anti-RABV após a vacinação (e também após o reforço). No entanto, os títulos reduzem-se, atingindo níveis 0,5UI/mL em 70% dos animais durante o intervalo antes do reforço. Assim, vacinação de reforço contra a raiva em bovinos, utilizando-se as vacinas atuais, deve ser realizada em intervalo inferior a um ano, de forma a manter os níveis de anticorpos neutralizantes na maioria dos animais.

Serological response to rabies virus induced by commercial vaccines in cattle / Resposta sorológica ao vírus da raiva induzida por vacinas comerciais em bovinos

The antibody response to rabies virus (RABV) induced by commercial vaccines in heifers was investigated. For this, 84 heifers were vaccinated twice (30 days interval) with each of four vaccines (G1 = 14 animals; G2 = 24; G3 = 22 and G4 = 24) and received a booster vaccination 360 days later. Serum samples collected at different intervals after vaccination and 30 days after booster were submitted to a virus neutralizing (VN) assay for RABV antibodies. Thirty days after the second vaccine dose, 92% of the immunized animals presented VN titers 0.5UI/mL (geometric medium titers [GMT] 1.7 to 3.8UI/mL). At the day of the booster (360 days post-vaccination); however, the percentage of animals harboring antibody titers 0.5UI/mL had dropped to 31% (0-80% of the animals, depending on the vaccine), resulting in lower GMT (0.1 to 0.6UI/mL). Booster vaccination at day 360 resulted in a detectable anamnestic response in all groups, resulting in 83% of animals (65 to 100%) harboring VN titers 0.5UI/mL thirty days later (GMT 0.6 to 4.3UI/mL). These results indicated that these vaccines were able to induce an adequate anti-RABV response in all animals after prime vaccination (and after booster as well). However, the titers decreased, reaching titers 0.5UI/mL in approximately 70% of animals within the interval before the recommended booster. Thus, booster vaccination for rabies in cattle using the current vaccines should be performed before the recommended one-year interval, as to maintain neutralizing antibodies levels in most vaccinated animals.(AU)

A resposta sorológica contra o vírus da raiva (RABV) induzida por vacinas comerciais foi investigada em bovinos. Para isso, 84 novilhas foram vacinadas duas vezes (30 dias de intervalo) com cada vacina (G1 = 14 animais; G2 = 24; G3 = 22 e G4 = 24) e receberam uma vacinação de reforço 360 dias depois. Amostras de soro coletadas em diferentes momentos após a vacinação e após o reforço vacinal foram submetidas ao teste de vírus neutralização (VN) para detecção de anticorpos contra o RABV. Trinta dias após a segunda dose vacinal, 92% dos animais apresentaram títulos neutralizantes 0,5UI/mL (GMT 1,7 a 3,8UI/mL). Porém, no dia do reforço (360 dias pós-vacinação), a porcentagem de animais que ainda apresentava títulos 0,5UI/mL havia se reduzido a 31% dos animais (0 a 80%, dependendo da vacina), resultando em baixos TMGs (0,1 a 0,6UI/mL). A vacinação de reforço no dia 360 resultou em resposta anamnéstica em todos os grupos, resultando em 83% (65 a 100%) de animais com títulos VN 0,5UI/mL trinta dias após (GMT 0,6 a 4,3UI mL-1). Esses resultados indicam que as vacinas avaliadas induzem uma resposta adequada de anticorpos anti-RABV após a vacinação (e também após o reforço). No entanto, os títulos reduzem-se, atingindo níveis 0,5UI/mL em 70% dos animais durante o intervalo antes do reforço. Assim, vacinação de reforço contra a raiva em bovinos, utilizando-se as vacinas atuais, deve ser realizada em intervalo inferior a um ano, de forma a manter os níveis de anticorpos neutralizantes na maioria dos animais.(AU)

Estudo epidemiológico, socioambiental e sorológico de fatores determinantes para ocorrência de mordeduras de morcegos hematófagos em duas populações em áreas de Reserva Extrativista (RESEX) no nordeste do Pará

Dois surtos de raiva humana ocorreram na região Norte do Brasil no biênio 2017-2018. No Pará, a doença voltou a emergir no estado depois de 14 anos sem registro. São comuns na Amazônia comunidades, que vivem isoladas e às margens de fragmentos florestais, entrarem em contato com morcegos hematófagos, importantes reservatórios do vírus da raiva. A transmissão do vírus para as vítimas ocorre diretamente por meio da mordida do morcego em sua procura por sangue. Há necessidade de se conhecer os aspectos epidemiológicos relacionados às agressões para proteção dos indivíduos envolvidos e prevenção das mortes. Este estudo tem como objetivos i) caracterizar a espoliação por morcegos hematófagos em humanos em municípios da microrregião do Salgado; ii) verificar se indivíduos agredidos desenvolvem imunidade natural ao vírus rábico e iii) avaliar o custo x benefício para pré-exposição das pessoas sob risco da agressão por morcegos na região. As análises serão conduzidas a partir das informações do Sistema de Informação de Agravos de Notificação (SINAN) a respeito do atendimento antirrábico dos municípios de São João da Ponta e Curuçá, e do Sistema Nacional de Imunização (SI-PNI) e Sistema de Insumos Estratégicos (SIES), com os dados do estado do Pará. Para caracterização dos agredidos serão aplicados questionários semiestruturados, enquanto que a verificação da imunidade será conduzida por meio de análise sorológica. Os dados parciais revelaram que, em São João da Ponta, para cada indivíduo registrado no SINAN existem 12,2 indivíduos que não procuram atendimento médico após agressão por morcegos. Esses indivíduos foram mordidos mais de quatro vezes no período de estudo (variação de 1-23 mordidas) e desconheciam o risco de contrair a raiva a partir das mordeduras (95,4%). Um novo perfil de agredidos foi descrito, destacando homens, catadores de caranguejo ou pescadores, em idade adulta como os mais vulneráveis. Ainda, um novo comportamento do morcego hematófago foi indicado, quando esses animais invadem os barcos em busca de alimento. A Reserva Extrativista (Resex) Mãe Grande de Curuçá foi a localidade mais apontada como área propícia para agressão. Portanto, as análises sorológicas serão conduzidas com indivíduos dessa região. A falta de conhecimento sobre a raiva pode ser a principal razão pela não procura ao atendimento médico das vítimas, sendo necessário o implemento de campanhas educativas e de vacinação em massa nessas comunidades. É destacada a necessidade de uma adaptação da ficha do SINAN quando a espécie agressora é o morcego incluindo a localidade provável da agressão para identificar as áreas de risco e implementar ações de vigilância da raiva, tendo em vista que a maioria das vítimas não foram mordidas em suas residências. Espera-se que as análises do custo-benefício, ainda não conduzidas, revelem as vantagens em direcionar as medidas preventivas para essa população sob risco e desprovida de atenção médica.

Human rabies transmitted by bats re-emerged in the northern region of Brazil in the years 2017/2018, after 14 years with no records of the disease. This re-emergence is worrying for the populations of the Amazon region, since reports of spoliation by blood-sucking bats are common in the region, in communities that live in isolation and on the margins of forest fragments. Transmission of the virus from bats to people occurs mainly through biting. In this context, knowledge of the epidemiological aspects related to bat attacks is essential for the adoption of protective measures by vulnerable human populations and the prevention of deaths. Thus, the present study aims to: i) characterize spoliation by blood-sucking bats in humans in two municipalities in the Salgado micro-region; ii) check the seroprevalence for the rabies virus in battered individuals. Descriptive analyzes were conducted based on information from the Notifiable Diseases Information System (SINAN) regarding anti-rabies care in the municipalities of São João da Ponta and Curuçá, with data from the state of Pará. A questionnaire was applied to characterize the victims. semi-structured for all 124 individuals in the study, while the titration of antibodies to the virus was performed using the Rapid Fluorescent Focus Inhibition Test (RFFIT) and Enzyme Linked Immunono Sorbent Assay (ELISA) methods, in 58 individuals, residents of the municipality of Curuçá-PA. In São João da Ponta, for each individual registered with SINAN, there are 12.2 individuals who do not seek medical attention after batting by bats. These individuals were bitten more than four times during the study period (range 1-23 bites) and were unaware of the risk of contracting rabies from bites (95.4%). A new profile of the attacked was described, highlighting men, crab scavengers or fishermen, in adulthood, as the most vulnerable. Still, a behavior of the hematophagous bat that has not yet been described was reported by interviewees, which would be the attack of bats on humans in vessels close to the coast. The Mãe Grande de Curuçá Extractivist Reserve (RESEX) was the location most mentioned as an area conducive to aggression; therefore, serological analyzes were conducted with individuals living in the municipality of Curuçá. These individuals answered an epidemiological questionnaire in which the answers were the basis for the descriptive analysis of the study. These people were between 03 and 69 years old, the majority of whom were fishermen (60.4%) from mangrove areas, male (75.4%). Among the 100% vaccinated individuals, they had IgG against the rabies virus and 55.5% of them also had IgM. The titer of neutralizing antibodies (AcN) was 0.5UI / mL in 50% of the individuals in this group, 81.8% were assaulted once in their lives and 56.4% received an incomplete vaccination schedule (1-4 doses), without application of serum (37.5%). Among those not vaccinated, 35% had IgM and 90% IgG. AcN 0.5 IU / mL was detected in 7.5% of them, 17.5% had titers between 0.11 - 0.49 IU / mL and 75% had AcN 0.10 IU / mL. In this group, 21.5% had already been attacked more than five times in their life, and the last aggression had occurred between 2 months and 1 year (55.9%, while sleeping in huts (51.9%), during fishing activity. The fact that there are individuals with AcN titers for the rabies virus (25%) that are not vaccinated indicates a possible exposure to the virus related to the successive attacks by bats. However, in most of these cases (17.5%) these exposures did not induce a protective immune response. Unvaccinated individuals who presented protective titles need further investigation to rule out unequivocally the possibility of a vaccination that was omitted in the interview. This study proposes necessary changes in the SINAN form to assess the potential areas of bat attacks in the human population in Pará, and thus, promote prophylactic or early intervention strategies to help minimize treatment costs and to prevent the resurgence of human rabies. in the micro region of Salgado in the state of Pará, Brazil.

Indução de anticorpos neutralizantes contra herpesvírus bovino e vírus da diarreia viral bovina por vacinas comerciais e vacina experimental associada com diferentes adjuvantes

O alfaherpesvírus bovino 1 (BoHV-1) e o vírus da diarreia viral bovina (BVDV) são patógenos importantes em bovinos cujas perdas podem ser reduzidas pela vacinação. Este estudo avaliou a resposta sorológica induzida por vacinas comerciais e por uma vacina experimental inativada associada com diferentes adjuvantes. Para isso, grupos de novilhas foram imunizados duas vezes (com intervalo de 30 dias), com nove vacinas comerciais. Amostras de soro foram testadas pela técnica de neutralização viral (VN), para avaliar a indução de anticorpos neutralizantes para seus respectivos vírus, 30 dias após a segunda dose (D60). Para o teste de adjuvante, antígenos de BoHV-1 e BVDV-1 inativados foram combinados com seis adjuvantes diferentes e submetidos ao mesmo protocolo de imunização e sorologia. Sete de nove vacinas comerciais induziram anticorpos contra o BoHV-1 no dia D60, mas apenas três induziram títulos considerados protetores ( 16). A frequência de soroconversão entre as vacinas variou de 0% (0/10 dos animais) a 100% (10/10) e os títulos médios geométricos (GMT) variaram de 0 a 43. A frequência de soroconversão em títulos protetores foi de 100%, 37,5% e 25% para BoHV-1, respectivamente. Somente quatro vacinas induziram títulos neutralizantes contra o BVDV-1 e três contra BVDV-2 no D60. A frequência de soroconversão para o BVDV variou de 0% (0/10 animais) a 100% (10/10) e os títulos médios geométricos (GMT) variaram de 0 a 202. Apenas três vacinas conferiram títulos compatíveis com proteção (> 60). A frequência de soroconversão em títulos protetores foi de 55,5%, 42,8% e 12,5% para BVDV-1, respectivamente. Todas as formulações vacinais experimentais induziram títulos neutralizantes contra BoHV-1 no D60 (a frequência de soroconversão variou de 0% a 100% e o GMT variou de 2 a 20), mas apenas quatro induziram títulos protetores. A frequência de soroconversão em títulos protetores foi de 100%, 33,3%, 30% e 20%, respectivamente. Por outro lado, nenhuma das vacinas experimentais foi capaz de induzir anticorpos neutralizantes para BVDV no D60. Nas condições do presente estudo, a maioria das vacinas comerciais induziu resposta sorológica insatisfatória contra os vírus testados, sendo mais evidente para o BVDV. Entre as vacinas experimentais, o adjuvante Emulsigen - DL90 (DDA) foi o mais eficaz na indução de anticorpos contra o BoHV-1, mas não contra o BVDV. Estes resultados indicam a necessidade de reformulação da composição das vacinas e / ou dos protocolos de imunização, para obter resposta sorológica mais consistente para o BoHV-1 e, principalmente, para o BVDV.

Bovine alphaherpesvirus 1 (BoHV-1) and Bovine viral diarrhea virus (BVDV) are important pathogens of cattle whose losses may be prevented by vaccination. This study evaluated the serological response induced by commercial vaccines and by an experimental vaccine associated with different adjuvants. For this, groups of seronegative heifers were immunized twice (30 days apart) with nine commercial vaccines and tested for virus neutralizing (VN) antibodies to the respective viruses 30 days after the second vaccine dose (D60). For the adjuvant test, inactivated BoHV-1 and BVDV-1 antigens were combined with six different adjuvants and submitted to the same immunization and serology protocol. Seven out of nine commercial vaccines induced VN antibodies to BoHV-1 at day D60, but only three induced titers considered protective ( 16). The frequency of seroconversion among the vaccines varied from 0% (0/10 animals) to 100% (10/10) and the geometric mean titers (GMT) ranged from 0 to 43. The frequency of seroconversion in protective titers was 100%, 37,5% and 25%, respectively. Only four vaccines induced neutralizing titers to BVDV-1 and three to BVDV-2 at D60. The frequency of seroconversion to BVDV among the vaccines varied from 0% (0/10 animals) to 100% (10/10) and the geometric mean titers (GMT) ranged from 0 to 202. Only three vaccines conferred titers compatible with protection (>60). The frequency of seroconversion in protective titers was 55,5%, 42,8% and 12,5% for BVDV-1, respectively. All experimental vaccine formulations induced VN titers against BoHV-1 at D60 (frequency of seroconversion varied from 0% to 100% and GMT= varied from 2 to 20) and four induced protective titers. The frequency of seroconversion in protective titers was 100%, 33,3%, 30% and 20%, respectively. On the other hand, none of the experimental vaccines was able to induce VN antibodies to BVDV at D60. Under the conditions of the present study, most commercial vaccines induced unsatisfactory VN response against the tested viruses, most noticeably to BVDV. Among the experimental vaccines, the adjuvant Emulsigen - DL90 (DDA) was more effective to induce VN antibodies against BoHV-1, but not to BVDV. These results indicate the need for reformulation of vaccine composition and/or immunization protocols as to achieve more consistent serological response to BoHV-1 and, especially, to BVDV.

Resposta imune humoral de cães domésticos que receberam dose única de vacina antivírus da raiva / Humoral immune response of domestic dogs that received a single dose of rabies vaccine

O Programa Nacional de Profilaxia da Raiva tem como objetivo manter níveis imunogênicos protetores nos animais vacinados, com títulos de anticorpos neutralizantes (AcN) 0,5UI/mL. O objetivo deste estudo foi avaliar, de acordo com a idade, raça e o período entre a aplicação da vacina e a colheita do sangue, a resposta imunológica de cães que receberam dose única de vacina antivírus da raiva de cultivo celular. Neste estudo foram analisadas 432 amostras recebidas no Instituto Pasteur de São Paulo no triênio 2009-2011. Os dados foram analisados e a avaliação de AcN para o vírus da raiva foi realizada por meio do teste rápido de inibição de focos fluorescentes (RFFIT). Do total das amostras analisadas, 21,76% não possuíam títulos protetores. Dentre essas, 67,02% das amostras eram de filhotes e quando considerado o intervalo entre a data de aplicação da vacina e a colheita do sangue, 60,63% amostras não atingiram a titulação nos seis primeiros meses. Concluiu-se a partir do estudo desta amostragem a necessidade de uma segunda dose de vacina em filhotes, pois estes ficam mais suscetíveis à infecção pelo vírus da raiva, o que aumentaria a possibilidade de uma resposta rápida e duradoura.

The National Programme for Rabies Prevention aims to maintainimmunogenic protective levels in vaccinated animals, with titersof neutralizing antibodies (VNA) 0.5 IU / mL. The aim of thisstudy was to evaluate, according to age, race, and the periodof vaccination and blood collection, the immune response indogs that received a single dose of rabies vaccine virus in cellculture. In this study 432 samples received at the Pasteur Instituteof São Paulo in the triennium 2009-2011 were analyzed. Datawere analyzed and the evaluation of the VNA to rabies virus wasperformed by rapid fluorescent inhibition test foci (RFFIT). Of thetotal samples analyzed, 21.76% did not have protective titers.Among these, 67.02% samples were considered puppies andwhen the interval between the date of vaccine administration andblood collection, 60.63% samples did not reach the titration inthe first six months. It was concluded from this study sample theneed for a second dose of vaccine in puppies, as they are moresusceptible to infection by rabies virus, which would increase thepossibility of a rapid and durable response.

Resposta imune humoral de cães domésticos que receberam dose única de vacina antivírus da raiva / Humoral immune response of domestic dogs that received a single dose of rabies vaccine

O Programa Nacional de Profilaxia da Raiva tem como objetivo manter níveis imunogênicos protetores nos animais vacinados, com títulos de anticorpos neutralizantes (AcN) 0,5UI/mL. O objetivo deste estudo foi avaliar, de acordo com a idade, raça e o período entre a aplicação da vacina e a colheita do sangue, a resposta imunológica de cães que receberam dose única de vacina antivírus da raiva de cultivo celular. Neste estudo foram analisadas 432 amostras recebidas no Instituto Pasteur de São Paulo no triênio 2009-2011. Os dados foram analisados e a avaliação de AcN para o vírus da raiva foi realizada por meio do teste rápido de inibição de focos fluorescentes (RFFIT). Do total das amostras analisadas, 21,76% não possuíam títulos protetores. Dentre essas, 67,02% das amostras eram de filhotes e quando considerado o intervalo entre a data de aplicação da vacina e a colheita do sangue, 60,63% amostras não atingiram a titulação nos seis primeiros meses. Concluiu-se a partir do estudo desta amostragem a necessidade de uma segunda dose de vacina em filhotes, pois estes ficam mais suscetíveis à infecção pelo vírus da raiva, o que aumentaria a possibilidade de uma resposta rápida e duradoura.(AU)

The National Programme for Rabies Prevention aims to maintainimmunogenic protective levels in vaccinated animals, with titersof neutralizing antibodies (VNA) 0.5 IU / mL. The aim of thisstudy was to evaluate, according to age, race, and the periodof vaccination and blood collection, the immune response indogs that received a single dose of rabies vaccine virus in cellculture. In this study 432 samples received at the Pasteur Instituteof São Paulo in the triennium 2009-2011 were analyzed. Datawere analyzed and the evaluation of the VNA to rabies virus wasperformed by rapid fluorescent inhibition test foci (RFFIT). Of thetotal samples analyzed, 21.76% did not have protective titers.Among these, 67.02% samples were considered puppies andwhen the interval between the date of vaccine administration andblood collection, 60.63% samples did not reach the titration inthe first six months. It was concluded from this study sample theneed for a second dose of vaccine in puppies, as they are moresusceptible to infection by rabies virus, which would increase thepossibility of a rapid and durable response.(AU)

AVALIAÇÃO SOROEPIDEMIOLÓGICA DE CÃES IMUNIZADOS CONTRA A RAIVA COM VACINA DE CULTIVO CELULAR EM CAMPANHA ANUAL DE VACINAÇÃO NO MUNICÍPIO DE BOTUCATU/SP

A raiva é uma zoonose transmitida pelo vírus do gênero Lyssavirus, e é considerada uma das enfermidades mais temidas no mundo devido à sua alta letalidade e inexistência de tratamento eficaz. Anualmente morrem mais de 50 mil pessoas por raiva em países subdesenvolvidos. O cão é o principal transmissor da raiva humana nos centros urbanos, responsável por 99% dos casos e 92% dos tratamentos pós-exposição. No Brasil, a raiva animal se apresenta de forma endêmica. A vacinação é o método mais eficiente de prevenção da raiva em cães e, por consequência, a proteção à população humana. No município de Botucatu, SP, há mais de 30 anos não são diagnosticados casos de raiva canina, devido às campanhas anuais de vacinação contra a raiva realizadas há 50 anos. Em 2010, o Ministério da Saúde preconizou o uso da vacina contra a raiva animal de cultivo celular nas campanhas de vacinação em massa. Este estudo teve como objetivo avaliar a resposta imunológica de cães que receberam apenas doses da vacina de cultivo celular contra o vírus da raiva. Para consolidação do tamanho amostral considerou-se uma porcentagem de 80% de adesão com consentimento livre e esclarecido, erro de estimação da ordem de 4% e nível de confiança de 95%. O título de anticorpos para a raiva foi detectado pelo Microteste Simplificado de Inibição de Fluorescência - SFIMT. Todas as discussões analíticas no plano estatístico foram realizadas no nível de significância de 5%. Observou-se que 59,12% (428/724) dos cães possuíam título protetor (0,5 UI/mL) e 40,88% (296/724) não tinham desenvolvido titulação protetora de anticorpos contra a raiva. Constatou-se, ainda, que a idade, esterilização, tratamento, vermifugação, quantidade de doses de vacina recebida e o tempo após a administração da vacina são características associadas ao título de anticorpos contra a raiva. Contudo, o sexo, escore corporal, presença de sinais clínicos, tipo de alimentação, local de permanência, interação com outras vacinas e o serviço utilizado para a administração das vacinas não estão associados ao título sérico protetor.

Rabies is a zoonosis transmitted by the virus of the genus Lyssavirus and is considered one of the most feared diseases in the world due to its high lethality and lack of effective treatment. Annually more than 50,000 people die from rabies in underdeveloped countries. The dog is the main transmitter of human rabies, accounting for 99% of cases and 92% of post-exposure treatments. In Brazil, animal rabies presents itself endemic. Vaccination is the most effective method of preventing rabies in dogs and, consequently, protecting the human population. In the municipality of Botucatu, SP, for more than 30 years no cases of canine rabies have been diagnosed due to the annual campaigns of rabies vaccination applied 50 years. In 2010, the Ministry of Health advocated the use of the antirabies animal cell culture vaccine in mass vaccination campaigns. This study aimed to evaluate the immunological response of dogs that received only doses of the cell culture vaccine against the rabies virus. To consolidate the sample size, a percentage of 80% adherence with free and informed consent, an error of the order of 4% and a 95% confidence level were considered. The antibody titers for rabies were detected by the Simplified Fluorescence Inhibition Microtest - SFIMT. All statistical analyses were performed at a significance level of 5%. It was observed that 59.12% (428/724) of the dogs had a protective titer (0.5 IU / mL) and 40.88% (296/724) had not developed a protective titer of anti-rabies antibodies. It was also found that age, sterilization, treatment, deworming, amount of vaccine doses received and the time after administration of the vaccine are characteristics associated with the titer of antibodies against rabies. However, sex, body score, presence of clinical signs, type of feeding, place of residence, interaction with other vaccines and the service used for administration of the vaccines are not associated with the protective serum titer.

Serological survey of feline calicivirus and felid herpesvirus in Rio Grande do Sul, Brazil

Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidney) was used for viral amplification and for the VN assay. The viruses used in the assay were the isolate SV65/90 of FCV, and the isolate SV534/00 of FeHV-1, from the Setor de Virologia/ UFSM; which were well characterized in a previous study by our group. The serum samples were tested against 100-200 TCID 50/mL (tissue cellular infection dose 50/mL) of both viruses in the VN assay, and a serial dilution of the serum was performed, starting at 1:5 up to > 1:1280 for FCV and at 1:2 to > 1:256 for FeHV-1 in 96 wells plates. Neutralization titers were calculated as the reciprocal of the highest serum dilution able to inhibit the cytopathic effect. Concerning to the results obtained, the groups with the highest number of collected samples were the group of the male cats (44%, 277/630), the group of the cats with ages among one to five years old (36.3%, 229/630) and the group of non-vaccinated cats (94%, 592/630). Neutralizing antibodies against one or both viruses were detected in 53.6% (338/630) of the 630 cats sampled; 23% (145/630) of the cats were seropositive only to FCV, 14.4% (91/630) were seropositive only to FeHV-1 and 16.2% (102/630) were seropositive for both, FCV and FeHV1. Regarding the groups, a higher percentage of positive samples was found for the group of female cats (85.6%) and the group of cats over fi ve years old for both viruses (82.3%). Considering vaccination status, only 6% of the cats were vaccinated against FCV and/or FeHV-1, however not all vaccinated cats had neutralizing antibodies against the viruses, since only 50% of the vaccinated population were seropositive against FCV and 42.1% of them were seropositive for FeHV-1. Discussion: The data showed in the present study demonstrated that both viruses are circulating in the feline population sampled; and, it also revealed that FCV seems to be more prevalent among this population since the presence of antibodies against FCV were detected more frequently than antibodies against FeHV-1. The high number of non-reagent serum and non-vaccinated cats indicates that there is yet a large percentage of the cat population that is susceptible to infection. The application of vaccination programs according of the recommendations could help to prevent the infection and change the situation among the feline population sampled.

Serological survey of feline calicivirus and felid herpesvirus in Rio Grande do Sul, Brazil / Serological survey of feline calicivirus and felid herpesvirus in Rio Grande do Sul, Brazil

Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidne

Background: Feline calicivirus (FCV) and felid herpesvirus type 1 (FeHV-1) are widely distributed in the feline population. These viruses are the main cause of upper respiratory tract disease in this species, and FCV can also causes oral disease characterized by stomatitis and ulcers. Furthermore, FCV has been associated with a systemic hemorrhagic syndrome named FCV-associated virulent systemic disease (FCV-VSD), which has not yet been reported in Brazil. The aim of the present study was to investigate the presence of antibodies against FCV and FeHV-1 in the population of domestic felines from some counties of the Rio Grande do Sul State (RS), using a virus neutralizing (VN) assay. Materials, Methods & Results: A total of 630 feline serum samples collected between the years 2007 and 2011 were analyzed to detect antibodies against FCV and FeHV-1 by a VN assay. The serum samples came from cats admitted in veterinary clinics, household cats and cats examined in veterinary hospitals at three universities from Rio Grande do Sul State (RS) [UFRGS, UFSM and UPF]. The serum samples were classified according to the origin, gender, age and vaccination status of the cat. All animal handling procedures were performed under veterinary supervision and following the recommendations of the Brazilian Committee on Animal Experimentation. The feline cell line CRFK (Crandell-Rees feline kidne

Occurrence of neutralizing antibodies against BVDV-1 and BVDV-2 in cattle herds from Minas Gerais and São Paulo States, Brazil / Ocorrência de anticorpos neutralizantes contra o BVDV-1 e o BVDV-2 em rebanhos bovinos de Minas Gerais e São Paulo, Brasil

The occurrence of neutralizing antibodies against bovine viral diarrhea virus genotypes (BVDV-1 and BVDV-2) has been confirmed by virus neutralization test (VN) in samples of blood serum from 26 cattle herds which were not BVDV vaccinated, located in the states of Minas Gerais and São Paulo, Brazil. Ten blood samples were collected from each herd, five samples from 6 to 12-month-old calves and five samples from adult bovines. Of the total samples analyzed, 102 (39.2%) were reactive to BVDV, more specifically, 81 (31.1%) were reactive to BVDV-1 and BVDV-2, seven (2.7%) were reactive to BVDV-1 only and 14 (5.4%) were reactive to BVDV-2 only. Except for two herds, in all others at least one animal was detected reactive to BVDV, however, one of them was reactive to BVDV-2 only. In six herds, neutralizing antibodies were detected in blood serum from 6 to 12-month-old calves. Therefore, were indicative of recent BVDV infection and also suggested the likely presence of an infection source in the herd. The results showed the occurrence of neutralizing antibodies against BVDV genotypes in cattle herds located in the states analyzed, but these same results demonstrated the differences in the number of bovines reactive for BVDV-1 and BVDV-2, thus demonstrating the need to use strains from each genotype in VN tests for serological diagnosis of BVDV.

A ocorrência de anticorpos neutralizantes contra os genótipos do vírus da diarréia viral bovina (BVDV-1 e BVDV-2) foi determinada pelo teste de virusneutralização (VN) em amostras de soro sangüíneo provenientes de 26 rebanhos bovinos não vacinados contra o BVDV, localizados nos Estados de Minas Gerais e São Paulo, Brasil. Foram analisadas 10 amostras por rebanho, sendo cinco de bovinos adultos e cinco de bovinos com idade entre 6 e 12 meses. Do total de 260 amostras analisadas, 102 (39,2%) reagiram ao BVDV, das quais 81 (31,1%) foram reagentes tanto ao BVDV-1 quanto ao BVDV-2, sete (2,7%) reagiram apenas ao BVDV-1 e 14 (5,4%) reagiram apenas ao BVDV-2. Com exceção de dois rebanhos, nos demais foram detectados pelo menos um animal reagente ao BVDV, entretanto, foram detectados animais reagentes apenas ao BVDV-2 em um deles. Em seis rebanhos foram detectados anticorpos neutralizantes nos bovinos da faixa etária de 6 a 12 meses, sendo, portanto, indicativos da infecção recente pelo vírus e também sugestivos da provável presença da fonte de infecção no rebanho. Os dados obtidos mostraram a ocorrência de anticorpos neutralizantes contra os genótipos do BVDV em rebanhos bovinos localizados nos Estados analisados, mas os resultados apresentaram diferenças no número de bovinos reagentes ao BVDV-1 e ao BVDV-2, ressaltando assim a necessidade da utilização de estirpes de cada genótipo nos testes de VN para o diagnóstico sorológico do BVDV.

Comparação dos testes de virusneutralização contra os genótipos 1 e 2 do vírus da diarreia viral bovina (BVDV-1 e BVDV-2) em bovinos de rebanhos naturalmente infectados

The virusneutralization test (VN) results against bovine viral diarrhoea virus genotypes (BVDV-1 and BVDV-2), and the respective titers of antibodies, were compared in 1,925 serum samples collected from unvaccinated and naturally infected cattle herds, located in the states of São Paulo and Minas Gerais, Brazil. The proportion of reagent samples among the genotypes was evaluated by McNemar test and the antibody titers against BVDV-1 and BVDV-2 were compared by Wilcoxon test. There were no disagreement in the proportion of BVDV-1 and BVDV-2 reagent samples (P>0.05). However, there was a disagreement among titers of antibodies detected in the VN tests against BVDV genotypes (P 0.0001). Although the proportion of reagent animals to BVDV genotypes was similar, false negative results would be obtained if 67 samples (3.5%) had been submitted only to VN test against BVDV-1, and 51 samples (2.65%) only against BVDV-2. Some herds had higher titers of antibodies for BVDV-1, while others for BVDV-2, thus demonstrating the occurrence of infection by different virus genotypes among the analyzed herds. Therefore, these results demonstrated the need for inclusion of both BVDV genotypes in VN tests.

Os resultados dos testes de virusneutralização (VN) contra os genótipos do vírus da diarreia viral bovina (BVDV-1 e BVDV-2), bem como os respectivos títulos de anticorpos, foram comparados em 1.925 amostras de soro sanguíneo obtidas de rebanhos bovinos naturalmente infectados e não vacinados contra o BVDV, provenientes dos Estados de São Paulo e Minas Gerais. A proporção de amostras reagentes entre os genótipos foi analisada pelo Teste de McNemar, e os títulos de anticorpos das amostras reagentes ao BVDV-1 e ao BVDV-2 foram comparados pelo Teste de Wilcoxon. Não foi verificada discordância na proporção de bovinos reagentes ao BVDV-1 e ao BVDV-2 (P>0,05). No entanto, houve discordância entre os títulos de anticorpos detectados nos testes de VN contra os genótipos 1 e 2 do BVDV (P 0,0001). Embora a proporção de animais reagentes contra ambos os genótipos do BVDV tenha sido semelhante, resultados falso-negativos seriam obtidos se 67 amostras (3,5%) tivessem sido submetidas apenas ao teste de VN, para o BVDV-1, e em 51 amostras (2,65%), apenas para o BVDV-2. Alguns rebanhos apresentaram títulos de anticorpos superiores para o BVDV-1, enquanto outros para BVDV-2, demonstrando assim a ocorrência da infecção pelos diferentes genótipos do vírus entre os rebanhos analisados. Portanto, tais resultados demonstraram a necessidade da inclusão de ambos os genótipos do BVDV nos testes de VN.

Comparação dos testes de virusneutralização contra os genótipos 1 e 2 do vírus da diarreia viral bovina (BVDV-1 e BVDV-2) em bovinos de rebanhos naturalmente infectados

The virusneutralization test (VN) results against bovine viral diarrhoea virus genotypes (BVDV-1 and BVDV-2), and the respective titers of antibodies, were compared in 1,925 serum samples collected from unvaccinated and naturally infected cattle herds, located in the states of São Paulo and Minas Gerais, Brazil. The proportion of reagent samples among the genotypes was evaluated by McNemar test and the antibody titers against BVDV-1 and BVDV-2 were compared by Wilcoxon test. There were no disagreement in the proportion of BVDV-1 and BVDV-2 reagent samples (P>0.05). However, there was a disagreement among titers of antibodies detected in the VN tests against BVDV genotypes (P 0.0001). Although the proportion of reagent animals to BVDV genotypes was similar, false negative results would be obtained if 67 samples (3.5%) had been submitted only to VN test against BVDV-1, and 51 samples (2.65%) only against BVDV-2. Some herds had higher titers of antibodies for BVDV-1, while others for BVDV-2, thus demonstrating the occurrence of infection by different virus genotypes among the analyzed herds. Therefore, these results demonstrated the need for inclusion of both BVDV genotypes in VN tests.

Os resultados dos testes de virusneutralização (VN) contra os genótipos do vírus da diarreia viral bovina (BVDV-1 e BVDV-2), bem como os respectivos títulos de anticorpos, foram comparados em 1.925 amostras de soro sanguíneo obtidas de rebanhos bovinos naturalmente infectados e não vacinados contra o BVDV, provenientes dos Estados de São Paulo e Minas Gerais. A proporção de amostras reagentes entre os genótipos foi analisada pelo Teste de McNemar, e os títulos de anticorpos das amostras reagentes ao BVDV-1 e ao BVDV-2 foram comparados pelo Teste de Wilcoxon. Não foi verificada discordância na proporção de bovinos reagentes ao BVDV-1 e ao BVDV-2 (P>0,05). No entanto, houve discordância entre os títulos de anticorpos detectados nos testes de VN contra os genótipos 1 e 2 do BVDV (P 0,0001). Embora a proporção de animais reagentes contra ambos os genótipos do BVDV tenha sido semelhante, resultados falso-negativos seriam obtidos se 67 amostras (3,5%) tivessem sido submetidas apenas ao teste de VN, para o BVDV-1, e em 51 amostras (2,65%), apenas para o BVDV-2. Alguns rebanhos apresentaram títulos de anticorpos superiores para o BVDV-1, enquanto outros para BVDV-2, demonstrando assim a ocorrência da infecção pelos diferentes genótipos do vírus entre os rebanhos analisados. Portanto, tais resultados demonstraram a necessidade da inclusão de ambos os genótipos do BVDV nos testes de VN.

Comparação dos testes de virusneutralização contra os genótipos 1 e 2 do vírus da diarreia viral bovina (BVDV-1 e BVDV-2) em bovinos de rebanhos naturalmente infectados

The virusneutralization test (VN) results against bovine viral diarrhoea virus genotypes (BVDV-1 and BVDV-2), and the respective titers of antibodies, were compared in 1,925 serum samples collected from unvaccinated and naturally infected cattle herds, located in the states of São Paulo and Minas Gerais, Brazil. The proportion of reagent samples among the genotypes was evaluated by McNemar test and the antibody titers against BVDV-1 and BVDV-2 were compared by Wilcoxon test. There were no disagreement in the proportion of BVDV-1 and BVDV-2 reagent samples (P>0.05). However, there was a disagreement among titers of antibodies detected in the VN tests against BVDV genotypes (P 0.0001). Although the proportion of reagent animals to BVDV genotypes was similar, false negative results would be obtained if 67 samples (3.5%) had been submitted only to VN test against BVDV-1, and 51 samples (2.65%) only against BVDV-2. Some herds had higher titers of antibodies for BVDV-1, while others for BVDV-2, thus demonstrating the occurrence of infection by different virus genotypes among the analyzed herds. Therefore, these results demonstrated the need for inclusion of both BVDV genotypes in VN tests.

Os resultados dos testes de virusneutralização (VN) contra os genótipos do vírus da diarreia viral bovina (BVDV-1 e BVDV-2), bem como os respectivos títulos de anticorpos, foram comparados em 1.925 amostras de soro sanguíneo obtidas de rebanhos bovinos naturalmente infectados e não vacinados contra o BVDV, provenientes dos Estados de São Paulo e Minas Gerais. A proporção de amostras reagentes entre os genótipos foi analisada pelo Teste de McNemar, e os títulos de anticorpos das amostras reagentes ao BVDV-1 e ao BVDV-2 foram comparados pelo Teste de Wilcoxon. Não foi verificada discordância na proporção de bovinos reagentes ao BVDV-1 e ao BVDV-2 (P>0,05). No entanto, houve discordância entre os títulos de anticorpos detectados nos testes de VN contra os genótipos 1 e 2 do BVDV (P 0,0001). Embora a proporção de animais reagentes contra ambos os genótipos do BVDV tenha sido semelhante, resultados falso-negativos seriam obtidos se 67 amostras (3,5%) tivessem sido submetidas apenas ao teste de VN, para o BVDV-1, e em 51 amostras (2,65%), apenas para o BVDV-2. Alguns rebanhos apresentaram títulos de anticorpos superiores para o BVDV-1, enquanto outros para BVDV-2, demonstrando assim a ocorrência da infecção pelos diferentes genótipos do vírus entre os rebanhos analisados. Portanto, tais resultados demonstraram a necessidade da inclusão de ambos os genótipos do BVDV nos testes de VN.

Humoral immune response in capuchin monkeys (Cebus apella) after vaccination with inactivated suckling mouse brain rabies vaccine: comparison of two schedules of immunization / Resposta imune humoral de macacos-pregos (Cebus apella) após vacinação com vacina anti-rábica inativada produzida em cérebros de camundongos lactentes: comparação de dois esquemas de imunização

Foram vacinados contra a raiva, dois grupos de macacos-pregos adultos, com a vacina inativada preparada em cérebros de camundongos lactentes, administrada pela via intramuscular, na Fundação Parque Zoológico de São Paulo. Os animais em momento algum haviam sido imunizados contra a raiva. O grupo I consistia de nove animais, que receberam três doses de 1,0 mL nos dias 0, 30 e uma dose de reforço aos 210 dias, e o grupo II continha 10 animais que receberam duas doses de 1,0 mL no dia 0 e uma dose de reforço aos 210 dias. As amostras de sangue foram colhidas aos 0,30°,60°,90°, 150°, 210°, 240°, 300° e 365° dias, e os anticorpos neutralizantes titulados pela técnica simplificada da inibição de focos fluorescentes. A vacina induziu uma resposta imune de curta duração com títulos de anticorpos neutralizantes acima de 0.5 UI/ mL em ambos os grupos; entretanto a resposta imune persistiu por apenas 54,9 mais ou menos 57,0 e 36,1 mais ou menos 60,2 dias nos Grupos I e II respectivamente após a primo vacinação, e, por apenas 62,6 mais ou menos 74,0 e 86,4 mais ou menos 61,5 dias nos Grupos I e II respectivamente após o reforço. Não houve diferença estatística significante entre os grupos estudados (p > 0,05).(AU)