Send to:

Choose Destination
See comment in PubMed Commons below
Vector Borne Zoonotic Dis. 2014 May;14(5):317-23. doi: 10.1089/vbz.2013.1424. Epub 2014 Apr 18.

Evaluation of the performance of a rapid enzyme-linked immunosorbent assay in the detection of Anaplasma phagocytophilum antibodies in horses.

Author information

  • 11 Department of Bio-Pathological Sciences and Hygiene of Animal and Food Production, Faculty of Veterinary Medicine, University of Perugia , Perugia, Italy .


The aim of this study was to evaluate the performance of a commercially available rapid enzyme-linked immonosorbent assay, the Snap® 4Dx test, in the detection of Anaplasma phagocytophilum antibodies in horses. Two hundred apparently healthy horses (asymptomatic) and 244 animals showing clinical symptoms (symptomatic), were tested for A. phagocytophilum immunoglobulin G (IgG) antibodies using both the Snap® 4Dx kit and an indirect fluorescence antibody test (IFAT), with the latter serving as a comparative test. Horses belonging to the symptomatic group were also tested for evidence of active infection with A. phagocytophilum by analysis of IFAT IgM titers and PCR assay amplifying a specific fragment of the 16S rRNA gene. The overall agreement between the results obtained using the two tests, as well as the relative performance exhibited by the Snap® 4Dx test in the two groups, was assessed. Forty of the 45 animals (89%) testing positive for IgG antibodies using IFAT were correctly identified using Snap® 4Dx testing. The agreement between the results of the two tests was very high (k>0.9), with almost identical performances in both symptomatic and asymptomatic animals. Conversely, within the symptomatic group, only 44% (no. 11/25) of Snap® 4Dx positives appeared to be associated with a state of active infection, whereas the remaining 56% (no. 14/25) were related both to not infected animals (no. 1) and to horses whose status of infection needed further evaluations to be confirmed (no. 13/25). This study suggests that the Snap® 4Dx test could represent a valid screening method for use during epidemiological surveys of equine populations. Nevertheless, in-clinic application of the test does not appear to be merited.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Mary Ann Liebert, Inc.
    Loading ...
    Write to the Help Desk