Search

In dogs, canine parvovirus (CPV) enteritis is associated with high morbidity and fatality rates requiring early diagnosis to facilitate treatment and reduce its spread. In recent times, various commercial immunochromatographic (IC) test kits are available for its rapid diagnosis, which require an assessment of their accuracy. Therefore, precision of a point-of-care IC combination test kit for canine coronavirus (CCoV)/CPV faecal antigen detection was evaluated in this study. Multicentred random faecal samples from 115 dogs with gastroenteritis were checked for the presence of CPV antigens using the SensPERT IC combination test kit and the result was compared with polymerase chain reaction (PCR) as a reference test. Parvovirus was detected in 105 (91.3%) and 108 (93.9%) faecal samples by the point-of-care test kit and PCR, respectively. The point-of-care IC test kit showed 95.4% relative sensitivity, 71.4% specificity, 98.1% positive predictive value, 50.0% negative predictive value, and 93.9% accuracy comparable to conventional PCR in the samples tested. This point-of-care test kit also demonstrated a fair positive likelihood ratio (3.34), a very low negative likelihood ratio (0.07) and a moderate agreement (Kappa = 0.6) compared with conventional PCR. This test kit has shown to be very useful in the screening of dogs for CPV infection, and is a reliable alternative for diagnosing CPV both in conventional laboratories and remote areas without laboratories. Negative results in the IC testing with high suspicion of CPV infection should be further confirmed using superior test such as PCR., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Canine parvovirus (CPV) is a fast-evolving single-stranded DNA virus that causes severe and fatal gastrointestinal disease in dogs. Lately, several mutations affecting viral protein (VP) capsid resulting in highly pathogenic variants with distinctive immunological and clinicopathological characteristics abound. This study involved screening stools of 44 randomly selected clinical cases of canine gastroenteritis from 4 cities (Ibadan, Jos, Makurdi, and Zaria) in Nigeria for CPV antigen using an on-the-spot immunoassay test kit, as well as, molecular detection of viral nucleic acid by polymerase chain reaction. Subsequently, nucleic acid sequencing of 1195-bp amplicons encompassing the VP2 encoding region was done. The resultant 40 high-quality amino acid sequences obtained were analysed for the identification and grouping of the viruses into their discrete variants - CPV-2a, CPV-2b, or CPV-2c, using key amino acids substitutions - Asn, Asp, or Glu respectively at position 426 of the VP2 gene. One-third (11/40; 27.5%) of the analysed sequences were identified as CPV-2a and two-third (29/40; 72.5%) as CPV-2c. The original CPV and CPV-2b were not detected. Also, the "new CPV-2a variant" with mutation S297A identified had two additional mutations (Y324I and T440A) associated with selective pressure and vaccination failure in their sequences. Similarly, unique CPV-2c mutants carrying genetic markers (S297A, Y324I, and Q370R) that are highly related to CPVs of Asian origin were observed. These findings revealed a high level of divergence of existing CPVs in circulation; suggesting that CPV is rapidly evolving in Nigeria lately., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Canine parvovirus (CPV) the causative agent of canine parvovirus enteritis is an intractable pathogen of dogs characterised by mutations, evolutionary changes and eventual vaccine failure. The disease is a serious problem in dogs with limited studies conducted in Nigeria. Therefore, this study was designed to characterise the subtypes of CPV isolates in six commonly used vaccines and 157 clinical samples collected from seven states in Nigeria from June 2016 to March 2018. Faecal samples collected from the clinical cases were subjected to in-clinic immunoassay to detect viral antigens. Polymerase chain reaction (PCR) was used to amplify viral VP2 gene in the samples and commonly used vaccines in Nigeria. Thereafter, PCR products were sequenced and analysed. The result showed that 93.0% of the dogs tested positive for CPV in both assays; 72.8% were puppies less than six months old, with 58.3% of them vaccinated. Partial VP2 gene sequence and phylogenetic analysis of 11 random clinical samples showed that CPV-2c 7(63.6%) and CPV-2a 4(36.4%) were the predominant subtypes in Nigeria; with genetic signatures that are 98.7% to 99.9% closely related to Asian and European strains, respectively. No CPV-2b was detected. Amino acid mutation analysis divulged some imperative transmutation sites: D305Y, Y324I, Q370R, N375D, T440A, Y444S, I447M and Y451C in the isolates. The viruses in the vaccines were characterised as the wild-type CPV. The genetic variability, viral population heterogeneity and phylogenetic linkage with isolates from other countries probably suggest transboundary migrations and local differentiations are contributing to continuous CPV evolution and vaccine failure in Nigeria., (Copyright © 2020. Published by Elsevier B.V.)