Molecular detection and clinical aspects of porcine circovirus 3 infection in pigs from Brazil / [Detecção molecular e aspectos clínicos da infecção por circovírus suíno 3 em suínos do Brasil]

Porcine circovirus 3 (PCV-3) DNA has been detected in serum samples from apparently healthy pigs as well as pigs with different clinical conditions. Molecular detection of PCV-3 was observed in swine serum samples from Southeastern - Brazil using a nested PCR designed specifically for this study. The epidemiology and clinical aspects of PCV-3 infection were evaluated. The samples originated from 154 pigs of both genders from different production phases and with different clinical presentations, sampled from 31 pig farms visited between 2013 and 2018. In this study, PCV-3 was detected in 26.7% of samples from all populations across varying ages. Statistical association (P=0.0285) was observed only between animals with respiratory signs and PCV-3; no PCV-3-positive animal had diarrhea. No statistical association was observed between PCV-3 and age, or gender of the pigs. Because PCV-3 is a newly discovered virus, there is very little information about its epidemiology. We hope that these data can help in future studies investigating PCV-3 epidemiology.(AU)

O DNA do circovírus suíno 3 (PCV-3) foi detectado em amostras de soro de suínos aparentemente saudáveis, bem como em suínos com diferentes condições clínicas. A detecção molecular do PCV-3 foi observada em amostras de soro de suínos da região Sudeste do Brasil, com uma nested PCR desenhada especificamente para este estudo. A epidemiologia e os aspectos clínicos da infecção por PCV-3 foram avaliados. As amostras foram coletadas de 154 suínos de ambos os sexos, de diferentes fases de produção e com diferentes sinais clínicos. Os animais pertenciam a 31 granjas visitadas entre 2013 e 2018. Neste estudo, o PCV-3 foi detectado em 26,7% das amostras de animais saudáveis e de animais com variados sinais clínicos, de ambos os sexos e de idades variadas. Associação estatística (P=0,0285) foi observada apenas entre animais com sinais respiratórios e PCV-3; nenhum animal positivo para PCV-3 apresentava diarreia. Não foi observada associação estatística entre o PCV-3 e a idade ou o sexo dos suínos. Por se tratar de um vírus recém-descoberto, existem poucas informações sobre sua epidemiologia. Espera-se que os dados deste trabalho possam contribuir para futuros estudos sobre a epidemiologia do PCV-3.(AU)

Wolbachia spp. interfere na detecção molecular de Ehrlichia canis e Anaplasma platys em cães com microfilaremia / Wolbachia spp. interferes with molecular detection of Ehrlichia canis and Anaplasma platys in microfilaremic dogs

This report aimed to study the interference in molecular testing for Ehrlichia canis and Anaplasma platys in blood of 155 dogs from the coastal region of Rio de Janeiro. Five Anaplasmataceae positive samples but negative for E. canis and A. platys, from microfilaremic animals, were chosen for sequencing. These sequences, when compared to Gen et Bank database, showed 88% to 100% similarity with Wolbachia spp. denoting an interference in the detection of DNA from other members of Anaplasmataceae, possibly due to a high concentration of Wolbachia spp. DNA.(AU)

Wolbachia spp. interfere na detecção molecular de Ehrlichia canis e Anaplasma platys em cães com microfilaremia / Wolbachia spp. interferes with molecular detection of Ehrlichia canis and Anaplasma platys in microfilaremic dogs

This report aimed to study the interference in molecular testing for Ehrlichia canis and Anaplasma platys in blood of 155 dogs from the coastal region of Rio de Janeiro. Five Anaplasmataceae positive samples but negative for E. canis and A. platys, from microfilaremic animals, were chosen for sequencing. These sequences, when compared to Gen et Bank database, showed 88% to 100% similarity with Wolbachia spp. denoting an interference in the detection of DNA from other members of Anaplasmataceae, possibly due to a high concentration of Wolbachia spp. DNA.(AU)

Comparison of three laboratorial tests for diagnosis of canine parvovirus infection / Comparação de três testes laboratoriais para diagnóstico da infecção pelo parvovírus canino

The aim of this study was to evaluate the rapid tests currently used for canine parvovirus (CPV) diagnosis: hemagglutination test (HA), enzyme immunoassay (EIA) and polymerase chain reaction (PCR). A total of 112 fecal samples collected from diarrheic puppies up to one year of age were tested. The EIA was able to detect CPV antigen in 44 samples. By HA, 32 samples tested highly positive with titers >128, eight tested weakly positive (titers 32 and 64) and 72 were negative (titers <16). Using PCR, 57 samples were found positive including 13 EIA-negative and 19 HA-negative samples. The best correlation was observed between EIA and PCR (88.4%). These tests were able to detect all types of CPV, including CPV-2c. Considering that 23%-33% of dogs presenting enteritis did not show infection by EIA nor HA, negative results from the antigen detection tests should be confirmed through molecular methods.(AU)

Avaliaram-se os métodos rápidos rotineiramente utilizados para diagnóstico da infecção por parvovírus canino (CPV): teste de hemaglutinação (HA), ensaio imunoenzimático (EIE) e reação em cadeia pela polimerase (PCR). Um total de 112 amostras fecais de cães diarreicos com até um ano de idade foi testado. O EIE foi capaz de detectar o antígeno do CPV em 44 amostras. Por HA, 32 amostras foram consideradas fortemente positivas com títulos >128, oito fracamente positivas (títulos 32 e 64) e 72 negativas (títulos <16). Por PCR, 57 amostras foram positivas incluindo 13 EIE-negativas e 19 HA-negativas. A melhor correlação foi observada entre EIE e PCR (88,4%). Os testes foram capazes de detectar todos os tipos de CPV, incluindo o CPV-2c. Considerando-se que em 23%-33% dos filhotes com enterite a infecção por CPV não foi diagnosticada pelos testes de EIE e HA, os resultados negativos nos testes de detecção de antígeno devem ser confirmados por meio de métodos moleculares.(AU)

Partial VP2 sequencing of canine parvovirus (CPV) strains circulating in the state of Rio de Janeiro, Brazil: detection of the new variant CPV-2c

Canine parvovirus (CPV) is the most important enteric virus for dogs and it seems to be undergoing continuous evolution, generating new genetic and antigenic variants throughout the world. The aim of this study was to analyze the distribution of CPV variants from 1995 to 2009 and to investigate the circulation of the new variant CPV-2c in Rio de Janeiro, Brazil. In addition, the clinical features of CPV infection were also reported. After CPV laboratorial confirmation by HA/HI and PCR, thirty-two fecal samples were analyzed by sequencing a 583-bp fragment of the VP2 gene. One sample, collected in 2008 was typed as the new type CPV-2c. All samples from 1995 to 2003 were identified as "new CPV-2a". From 2004 to 2006, both "new CPV-2a" and CPV-2b were observed. From 2006 to 2009, most of the samples were characterized as CPV-2b. The classical signs of CPV enteritis were observed in 16/18 CPV-2a and 5/13 CPV-2b infected puppies. These results show that continuous epidemiological surveillance of CPV strain distribution is essential for studying the patterns of CPV-2a and 2b spread and for determining whether the new variant CPV-2c has become permanently established in Brazilian canine population.

Clinical and epidemiological aspects of canine parvovirus (CPV) enteritis in the State of Rio de Janeiro: 1995 - 2004 / Aspectos clínicos e epidemiológicos da enterite por parvovírus canino (CPV) no estado do Rio de Janeiro: 1995-2004

This paper relates the clinical and epidemiological aspects of canine parvovirus infection (CPV) in the State of Rio de Janeiro from April 1995 to March 2004. A total of 341 fecal samples were collected from up to 6-months-old puppies with gastroenteritis. The diagnosis of CPV infection was confirmed by hemagglutination/ hemagglutination inhibition tests, enzyme immunoassay, virus isolation in cell culture or polymerase chain reaction. One hundred and fifty-seven samples (46 percent) were positive for CPV. No correlation among sex, breed or age and the occurrence of CPV infection was observed. The classical signs of parvoviral enteritis (anorexia, lethargy, vomiting and hemorrhagic fluid diarrhea) were observed in 70 percent of CPV-positive and in 60 percent of CPV-negative puppies. Although CPV could be detected throughout the studied period, its occurrence was significantly higher from June to September and November to December. These results show that CPV is still circulating in the State of Rio de Janeiro.(AU)

Este trabalho relata os aspectos clínicos e epidemiológicos da infecção pelo CPV no Estado do Rio de Janeiro, no período de abril de 1995 a março de 2004. Coletaram-se 341 amostras fecais de cães com até seis meses de idade que apresentavam gastrenterite. O diagnóstico da infecção pelo CPV foi confirmado através dos testes de hemaglutinação/inibição da hemaglutinação, ensaio imunoenzimático, isolamento viral em cultura de células ou reação em cadeia pela polimerase. Cento e cinqüenta e sete amostras (46 por cento) foram consideradas positivas para CPV. Não foi observada correlação entre sexo, raça ou idade e a ocorrência da infecção por CPV. Os sinais clínicos clássicos de parvovirose (vômito, anorexia, apatia e diarréia líquida hemorrágica) foram observados em 70 por cento dos animais positivos e 60 por cento dos animais negativos para CPV. O CPV foi detectado ao longo do período estudado, entretanto observou-se um aumento do número de casos positivos nos períodos de junho a setembro e novembro a dezembro. Estes resultados mostram que o CPV ainda circula no Estado do Rio de Janeiro.(AU)