Identificación de las cepas vacunales y las variantes de Parvovirus canino tipo 2 en muestras de caninos (Canis lupus familiaris)

Abstract

Canine Parvovirus type 2 (CPV-2) is a highly contagious viral disease that primarily affects young and unvaccinated dogs. It is characterized by an acute clinical presentation including vomiting, hemorrhagic diarrhea, fever, anorexia, panleukopenia, and severe dehydration, leading to high morbidity and mortality in the canine population. Its epidemiological dynamics are influenced by the emergence of variants (CPV-2a, CPV-2b, and CPV-2c), which increase the infective capacity of the virus and may compromise the effectiveness of traditional vaccination programs. The aim of this study was to differentiate vaccine strains from field strains of CPV-2 and subsequently identify CPV-2 variants in dogs suspected of infection using an ARMS-PCR assay. A total of 41 canine rectal swab samples were collected, from which genetic material was extracted for analysis using conventional PCR and ARMS-PCR. In an initial process control, 32 samples were deemed viable for amplification. PCR diagnosis revealed that 28 of these samples (87.5%) were positive for CPV-2. Subsequently, ARMS-PCR assays enabled the differentiation between vaccine and field strains and the determination of the viral variant present. Most cases corresponded to field strains. Among the 26 samples in which variants were identified, CPV-2c was the most prevalent (80.76%), followed by CPV-2b (15.39%) and CPV-2a (3.85%). In conclusion, the ARMS-PCR technique is an effective tool for distinguishing whether viral shedding in feces corresponds to vaccine or field strains, as well as for identifying circulating CPV-2 variants. These findings provide valuable information for optimizing prevention, control, and vaccination strategies against this disease.