Molecular prevalence of Porcine Circovirus 2 infection: foremost report in Southern states of India

Abstract

: Porcine circovirus 2 (PCV2) is the emerging viral pathogen in the swine associated with multi-systemic clinical and subclinical outcomes. This study aimed to detect molecular and serological prevalence of PCV2 infection from southern states of India. A total of 434 random samples comprising of serum (n=273), pooled postmortem tissues (n=109) and rectal, vaginal and nasal swabs (n=52) and were collected from PCV2 suspected and healthy swine populations of Tamil Nadu, Kerala, Andhra Pradesh, Telangana and Puducherry states in India during 2019 to 2021 were screened for PCV2 by specific polymerase chain reaction (PCR) assay. Of 434 samples screened, 12.2% (n=53) showed positivity to PCV2 genome. Statistical analysis of molecular prevalence of PCV2 within breed, age, sex and vaccination status revealed no significant (p>0.05) difference but there was a significant (p<0.05) difference in the prevalence of PCV2 among healthy and suspected swine populations. Suspected pigs had significantly higher prevalence of PCV2 in comparison to healthy. ELISA based PCV2 antibody screening in 176 non-vaccinated serum samples revealed sero-positivity of 44.8% (n=79). The molecular and seroprevalence of PCV2 is alarming in southern states of India, which necessitates the need for genotypic characterization and phylogenetic analysis and development of candidate vaccine for implementation of suitable prevention and control measures.