Study Proves Faecal Antigen Testing Alone Finds 2x More Parasitic Infections

While innovation in some areas of veterinary medicine has been quickly adopted, other more traditional methods, such as using faecal flotation for routine screening and diagnostics, persist in practices. Although the faecal floatation test was a significant advancement for faecal testing at the time, it's remained largely unchanged for more than 100 years, resulting in false negatives and an increased risk of zoonotic disease.

Veterinary practices today can enhance their parasite diagnostics by switching to faecal antigen testing, which improves both the scope and accuracy of faecal testing results. This testing method employs antibodies to detect specific proteins that are unique to certain organisms. The targeted protein is secreted or excreted by a parasite within the intestinal lumen of the infected animal, regardless of the parasite's egg production.

  The future of parasites is they have no future. Learn more about Faecal Dx antigen testing.

The fact that this method of testing does not require the identification of eggs is a crucial aspect of its efficacy as an accurate screening test for infected dogs or cats that are asymptomatic or may exhibit a range of clinical signs potentially associated with parasite infection.1-3

The Antigen Study

All small animal veterinary practices recognise the importance of faecal screening for both canine and feline wellness, but there's significant variability in the age and frequency of recommendations. The European Scientific Counsel Companion Animal Parasites (ESCCAP) takes a risk-based approach, recommending faecal examination or deworming at least four times per year for dogs and cats whose individual infection risk cannot be clearly assessed — with higher-risk animals potentially requiring monthly testing.4

Regardless of the frequency, the choice of diagnostic method matters. A recent faecal antigen study demonstrated significant results supporting the value of advanced diagnostic testing. In this retrospective study6, investigators compared faecal antigen testing and centrifugal flotation in 898,300 wellness testing samples. The samples were divided by age and species into six groups.

Within these age groups and species, all six antigen results were compared to any ova and parasite result from a standard faecal flotation test. The antigen test accurately screens for the most common and clinically relevant intestinal parasites, including roundworms, hookworms, whipworms, flea tapeworms, and Cystoisospora.5

Summary of Results

This vast retrospective study6 revealed several significant findings, including the following:

  • Overall, faecal antigen testing alone detected up to twice as many infections compared to centrifugal flotation alone.
  • Results were consistent across all age groups. While parasitism was identified more frequently in younger animals by both methods, parasitism is generally more common in younger age groups. Observing the number of parasites found by faecal antigen testing as pets age is more informative, and they should be on routine monthly parasite prevention.
  • Lastly, flotation rarely detects incremental, clinically relevant infections (0.2%–0.6% of all patients when common treatments are considered). However, faecal antigen testing was much more effective at identifying clinically relevant infections (9.4%) where treatment was indicated. As a clinician, this highlights the significant clinical information being missed during our patients' wellness exams.

What This Means for Veterinary Practices

In any study, it's crucial not only to understand the setup and results but also to know how to apply those findings to daily practice. Here, these discoveries can enhance the quality of faecal wellness and illness screening and diagnostic tests while contributing appropriate incremental revenue from the diagnostics profit centre of your practice.

These study results indicate that faecal antigen testing alone can identify 11 additional clinically relevant parasite infections per veterinarian per month (or 141 per year) in patients who otherwise appeared healthy and would not have detectable infections using flotation alone.

Take a moment to absorb that statistic. Eleven additional clinically relevant infections each month means 11 patients with a disease requiring treatment are currently being overlooked. It also implies 11 more patients may remain contagious to other animals in the house or neighbourhood or even to the humans in the home through zoonotic transfer. Furthermore, it emphasises 11 more animals that need a more comprehensive discussion regarding their monthly parasite prevention strategy.

As veterinary practices continually strive to enhance the quality of their medicine through innovation and efficiency, faecal antigen testing can help achieve both with a single sample sent to the reference lab. It's this type of innovation that needs to be embraced today, replacing the traditional methods of the past, to improve diagnostic accuracy and disease prevention.

References:

  1. Elsemore DA, Bezold T, Geng J, Hanna R, Tyrrell P, Beall M. Immunoassay for detection of Dipylidium caninum coproantigen in dogs and cats. J Vet Diagn Invest. 2023;35(6):671–678. DOI:10.1177/10406387231189193. https://pubmed.ncbi.nlm.nih.gov/37491878/.
  2. Elsemore DA, Geng J, Flynn L, Cruthers L, Lucio-Forster A, Bowman DD. Enzyme-linked immunosorbent assay for coproantigen detection of Trichuris vulpis in dogs. J Vet Diagn Invest. 2014;26(3):404–411. DOI: 10.1177/1040638714528500. https://pubmed.ncbi.nlm.nih.gov/24670954/.
  3. Elsemore DA, Geng J, Cote J, Hanna R, Lucio-Forster A, Bowman DD. Enzyme-linked immunosorbent assays for coproantigen detection of Ancylostoma caninum and Toxocara canis in dogs and Toxocara cati in cats. J Vet Diagn Invest. 2017;29(5):645–653. DOI:10.1177/1040638717706098. https://pubmed.ncbi.nlm.nih.gov/28424002/.
  4. ESCCAP. Worm Control in Dogs and Cats. ESCCAP Guideline 01, Seventh Edition. June 2025. Available at: https://www.esccap.org/uploads/docs/biu0jhej_0778_ESCCAP_GL1__English_2025_v21_1p.pdf
  5. Sweet S, Hegarty E, McCrann DJ, Coyne M, Kincaid D, Szlosek D. A 3-year retrospective analysis of canine intestinal parasites: faecal testing positivity by age, U.K. geographical region and reason for veterinary visit. Parasites and Vectors. 2021;14(1):173. DOI:10.1186/s13071-021-04678-6. https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-021-04678-6.
  6. Burton KW, Michael H, Drake C. The utility of coproantigen testing in screening populations. Vet Parasitol. Published online April 4, 2025. doi:10.1016/j.vetpar.2025.110459.

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Faecal Antigen Testing Study Overview

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A recent study demonstrates how veterinary practices today can enhance their parasite diagnostics by switching to faecal antigen testing.

Natalie Marks
DVM, CVJ

Dr. Marks is a veterinarian, previous veterinary hospital owner, consultant, media expert, national and international educator, and angel investor with over 20 years experience. She is a passionate communicator within multiple media formats, such as industry magazines and national conferences. She has won many industry awards, including the Dr. Erwin Small First Decade Award, given to the veterinarian who has contributed the most to organised veterinary medicine in his or her first decade of practice. Other notable awards that she has received are Petplan’s nationally recognised Veterinarian of the Year (2012), America’s Favorite Veterinarian by the American Veterinary Medical Foundation (2015), and Nobivac’s Veterinarian of the Year for her work on canine influenza (2017). The views and opinions in this piece are the author's own and do not necessarily reflect the views of either The Vetiverse or IDEXX.


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