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1.
PLoS One ; 9(11): e111779, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25365348

RESUMO

Canine parvovirus (CPV), a fast-evolving single-stranded DNA virus, comprises three antigenic variants (2a, 2b, and 2c) with different frequencies and genetic variability among countries. The contribution of co-infection and recombination to the genetic variability of CPV is far from being fully elucidated. Here we took advantage of a natural CPV population, recently formed by the convergence of divergent CPV-2c and CPV-2a strains, to study co-infection and recombination. Complete sequences of the viral coding region of CPV-2a and CPV-2c strains from 40 samples were generated and analyzed using phylogenetic tools. Two samples showed co-infection and were further analyzed by deep sequencing. The sequence profile of one of the samples revealed the presence of CPV-2c and CPV-2a strains that differed at 29 nucleotides. The other sample included a minor CPV-2a strain (13.3% of the viral population) and a major recombinant strain (86.7%). The recombinant strain arose from inter-genotypic recombination between CPV-2c and CPV-2a strains within the VP1/VP2 gene boundary. Our findings highlight the importance of deep-sequencing analysis to provide a better understanding of CPV molecular diversity.


Assuntos
Evolução Molecular , Genoma Viral , Parvovirus Canino/genética , Filogenia , Recombinação Genética , Animais , Sequência de Bases , Cães , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Dados de Sequência Molecular
2.
Vet Microbiol ; 166(1-2): 214-9, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-23850438

RESUMO

Canine parvovirus (CPV) comprises three antigenic variants (2a, 2b, and 2c) that are distributed globally with different frequencies and levels of genetic variability. CPVs from central Ecuador were herein analyzed to characterize the strains and to provide new insights into local viral diversity, evolution, and pathogenicity. Variant prevalence was analyzed by PCR and partial sequencing for 53 CPV-positive samples collected during 2011 and 2012. The full-length VP2 gene was sequenced in 24 selected strains and a maximum-likelihood phylogenetic tree was constructed using both Ecuadorian and worldwide strains. Ecuadorian CPVs have a remarkable genetic diversity that includes the circulation of all three variants and the existence of different evolutionary groups or lineages. CPV-2c was the most prevalent variant (54.7%), confirming the spread of this variant in America. Ecuadorian CPV-2c strains clustered in two lineages, which represent the first evidence of polyphyletic CPV-2c circulating in South America. CPV-2a strains constituted 41.5% of the samples and clustered in a single lineage. The two detected CPV-2b strains (3.8%) were clearly polyphyletic and appeared related to Ecuadorian CPV-2a or foreign CPV-2b strains. Besides the substitution at residue 426 that is used to identify the variants, two amino acid changes occurred in Ecuadorian strains: Val139Iso and Thr440Ser. Ser(440) occurred in a biologically relevant domain of VP2 and is here described for the first time in CPV. The associations of Ecuadorian CPV-2c and CPV-2a with clinical symptoms indicate that dull mentation, hemorrhagic gastroenteritis and hypothermia occurred more frequently in infection with CPV-2c than with CPV-2a.


Assuntos
Doenças do Cão/virologia , Variação Genética , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Parvovirus Canino/isolamento & purificação , Animais , Sequência de Bases , Doenças do Cão/epidemiologia , Cães , Equador/epidemiologia , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Parvovirus Canino/classificação , Filogenia
3.
Arch Virol ; 158(6): 1133-41, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23297117

RESUMO

Canine parvovirus (CPV) comprises three antigenic variants (2a, 2b, and 2c) with different frequencies and genetic variability among countries. Current CPV populations are considered to be spatially structured with relatively little movement of viruses between geographical areas. Here we describe the evolution and population dynamics of CPV in Uruguay from 2006-2011 using full-length capsid viral protein 2 (VP2) sequences. CPV-2c was the predominant variant in Uruguay for 4 years (2006-2009). The estimated time to the most recent common ancestor suggested that the CPV-2c variant appeared in Uruguay around 2004-2005. Comparative phylogenetic analysis revealed that South American CPV-2c strains did not emerge de novo but may have a European origin. In 2010, a remarkable epidemiological change occurred as a consequence of the emergence of a novel CPV-2a strain in the previously homogeneous CPV-2c population. The frequency of the novel CPV-2a strain increased to 85 % in 2011, representing the first example of a CPV-2a strain replacing a predominant CPV-2c strain in a dog population. The CPV-2a strains detected in 2010-2011 were not phylogenetically related to any other strain collected on the American continent but were identical to Asiatic strains, suggesting that its emergence was a consequence of a migration event. Taken together, our findings suggest that in the last decade, Uruguay has experienced two successive invasions by CPV-2c and CPV-2a variants of European and Asiatic origins, respectively. These results support the hypothesis that CPV invasion events are not rare in certain geographic regions and indicate that some current strains may exhibit an unexpectedly high invasion and replacement capability.


Assuntos
Parvovirus Canino/genética , Animais , Proteínas do Capsídeo/genética , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Genótipo , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Filogenia , Uruguai/epidemiologia
4.
Vet Microbiol ; 155(2-4): 214-9, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22014372

RESUMO

Canine parvovirus type 2 (CPV-2), which causes acute hemorrhagic enteritis in dogs, is comprised of three antigenic variants (2a, 2b, and 2c) that are distributed worldwide with different frequencies. Variant prevalence was analyzed in 150 CPV-2-positive samples collected from the Uruguayan dog population in 2007-2010. Samples were analyzed with polymerase chain reaction, restriction fragment length polymorphism, and sequencing of the coding region for the largest and most variable loop of the VP2 capsid protein. CPV-2c was the only strain detected from 2007 to 2009. Uruguayan CPV-2c showed high homogeneity in both nucleotide and amino acid sequences, indicating a low level of genetic variability. In 2010, an unexpected epidemiological change occurred in Uruguay as a consequence of the appearance of a novel CPV-2a strain. This variant rapidly spread through the Uruguayan dog population and was detected in 20 of the 52 cases (38%) analyzed in 2010. CPV-2a sequences were identical in all field viruses analyzed, and in addition to the characteristic 426Asn residue, the sequences showed amino acid substitutions (267Tyr, 324Ile, and 440Ala) not observed in the Uruguayan CPV-2c. These data and the first detection in April 2010 suggest that the CPV-2a variant recently emerged in Uruguay and underwent clonal expansion. This observation is the first case in which a CPV-2a variant increased its frequency in a dog population where CPV-2c was prevalent. Our results emphasize the dynamic changes in CPV variants and highlight the importance of ongoing surveillance programs to provide a better understanding of virus epidemiology.


Assuntos
Doenças do Cão/virologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/classificação , Animais , Proteínas do Capsídeo/genética , Cães , Infecções por Parvoviridae/virologia , Parvovirus Canino/genética , Parvovirus Canino/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Análise de Sequência de Proteína , Uruguai
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