Many German Horses Carry Antibodies Against Tapeworms, ELISA Study Finds

A new study from Germany, published open access in the journal Parasites & Vectors, set out to estimate how many horses in the country are positive for tapeworm antibodies, combining antibody tests with coproscopy and questionnaire data.

The researchers collected data in six federal states: Brandenburg, Bavaria, Lower Saxony, North Rhine-Westphalia, Saxony and Schleswig-Holstein. Coproscopy was performed using the Mini-FLOTAC technique on 970 samples. Antibodies against the Anoplocephala perfoliata excretory-secretory 12–13 kDa antigen complex were measured with two ELISA formats, one saliva-based (969 horses) and one plasma-based (957 horses), with 923 paired samples available. Questionnaire responses were used to assess risk factors associated with infection.

The contrast between the two diagnostic approaches was striking. Tapeworm eggs were detected in only 0.7% of faecal samples, that is 7 of 970 horses. By comparison, the saliva-based ELISA identified positive tapeworm results in 20.1% of horses, with 60.4% of the yards sampled having at least one positive animal. The plasma-based ELISA returned lower figures, with 11.0% of horses and 47.4% of yards testing positive.

The authors conclude from these ELISA results that horses in Germany are more frequently positive for Anoplocephalidae than indicated by Mini-FLOTAC. The antibody-detection approach, they note, has significant advantages for estimating the proportion of horses positive for tapeworms precisely because faecal routine examinations are often limited by low sensitivity.

Geography emerged as a major determinant of infection risk. In a multivariable analysis using generalised estimating equations for binomial data, based on the saliva ELISA results, horses from Brandenburg had the highest odds of testing positive, with an odds ratio of 18.7 and a positivity proportion of 42.1%. Horses from Lower Saxony, Saxony and North Rhine-Westphalia also showed significantly higher odds than the reference state, with odds ratios ranging from 4.1 to 12.4 and proportions between 17.4% and 32.2%.

Schleswig-Holstein, with a positivity proportion of 4.0%, served as the comparison group. Bavaria was the only state that did not differ significantly from it, showing an odds ratio of 2.7 and a proportion of 9.0%. These strong regional differences in saliva test positivity form a central finding of the study.

Age also mattered. Horses under one year old had significantly lower odds of testing positive, with an odds ratio of 0.41, as did horses older than five years, with an odds ratio of 0.43, compared with horses aged one to five years. Both differences were statistically significant at P < 0.001, suggesting that young adult horses carry the greatest infection burden in this dataset.

Co-infection patterns provided another signal. Strongyle faecal egg counts increased the odds of an individual horse being Anoplocephala-positive, with the odds rising 1.07-fold for every increase of 100 eggs in the count, also significant at P < 0.001. This association links the intensity of strongyle egg shedding with the likelihood of tapeworm antibody positivity in the same animals.

The relatively low number of horses treated against tapeworms, together with the pronounced regional variation the study documented, underpins the authors’ conclusion that applying tapeworm diagnostics in control programmes is important. Because antibody tests captured a far larger fraction of positive horses than egg counting, the findings argue for incorporating ELISA-based diagnostics rather than relying on coproscopy alone when assessing tapeworm exposure in German horse populations.

The study’s scope should be kept in view: it covered horses in six German federal states, used two antibody assays with somewhat different positivity rates, and identified risk factors through statistical modelling of cross-sectional data. The reported odds ratios and proportions describe associations within this sampled population, and the saliva and plasma ELISAs yielded different positivity estimates, with the saliva test producing the higher figure (20.1% vs 11.0%).

Subject of Research: Antibody-based detection of tapeworm infections in horses in Germany

Article Title: High proportion of horses in Germany positive for antibodies against Anoplocephalidae

Article References: Schmidt, J. S., Krücken, J., Matthews, J. B., Austin, C. J., Lightbody, K. L., Bartz, J., & von Samson-Himmelstjerna, G. (2026). High proportion of horses in Germany positive for antibodies against Anoplocephalidae. Parasites & Vectors. https://doi.org/10.1186/s13071-026-07731-4

Image Credits: AI Generated

DOI: 10.1186/s13071-026-07731-4

Keywords: horses, tapeworms, Anoplocephala perfoliata, ELISA, Germany, parasites, diagnostics, Mini-FLOTAC, risk factors, veterinary medicine, High, proportion