The diagnostic value of the droplet digital PCR for the detection of
bovine Deltapapillomavirus in goats by liquid biopsy
Abstract
In the present study, the highly pathogenic bovine Deltapapillomavirus
(δPV) was investigated by liquid biopsy in blood samples of 168
clinically normal goats using both droplet digital PCR (ddPCR) and
quantitative real time PCR (qPCR). Overall, ddPCR detected BPV E5 DNA in
~61.3% of the blood samples examined, while real time
qPCR revealed the virus in ~10.7% of the same samples.
Moreover, ddPCR showed BPV E5 DNA in ~78.8% of blood
samples from goats that were in close contact with cattle and in 20% of
blood samples from goats living in closed pens without any contact with
cattle. In addition, ddPCR revealed a single BPV genotype in
~59.2% and multiple genotypes in
~40.8% of goats harboring BPV DNA, while real time qPCR
detected single genotypes in ~17% and multiple
genotypes in ~1%. Of the BPV co-infections detected by
ddPCR, 28 (~67%) involved two genotypes, eight
(~19%) three genotypes, and six (~14%)
four genotypes. In contrast, real time qPCR revealed BPV co-infection by
two genotypes in only one sample and failed to detect co-infection by
three or four genotypes. BPV2 and BPV13 were the most prevalent viruses
responsible for single and multiple co-infections, respectively. The
present study showed that the ddPCR technique has much higher
sensitivity and specificity in the detection of these viruses, and
suggested that animal husbandry practices contribute to cross-species
transmission of BPVs.