Prevalence of Fasciola hepatica in dairy herds in England and Wales measured with an ELISA applied to bulk‐tank milk

Abstract

An ELISA developed to diagnose Fasciola hepatica infection in cattle by detecting serum antibodies was adapted and validated for use with samples of bulk-tank milk. The prevalence of the infection in 61 dairy herds was established by using serum antibody levels or faecal egg counts measured in a proportion of the cows in each herd. The correlation between the results of the ELISA and the herd seroprevalence was 0.83. Using a cut-off value of 27 per cent positive, the bulk-tank ELISA identified herds in which more than 25 per cent of the cows were infected with a diagnostic sensitivity of 96 per cent (95 per cent confidence interval 89 to 100 per cent) and a diagnostic specificity of 80 per cent (95 per cent confidence interval 66 to 94 per cent). By applying the ELISA to 623 herds in England and 445 herds in Wales, the prevalence of F hepatica infection in England was estimated to be 48 per cent (95 per cent confidence interval 46 to 54 per cent), and in Wales 86 per cent (95 per cent confidence interval 84 to 90 per cent).

Fasciola hepatica: epidemiology, perspectives in the diagnostic and the use of geoprocessing systems for prevalence studies

“…The great advantage of sampling milk is the ease of obtaining the sample compared to the invasive form (the collection of blood and/or faeces). In England and in Wales the number of diagnosed cases of fasciolosis in cattle increased significantly, especially in dairy cattle, although most chronic infections were diagnosed by the egg count method (SALIMI-BEJESTANI et al, 2005).…”

“…Early diagnosis of fascioliasis (during the prepatent period) using tests for the detection of antibodies may be essential to prevent the negative impact of the disease on productivity (SANCHEZ-ANDRADE et al, 2000;DIXIT;YADAV;SHARMA, 2004). Among the immunodiagnostic tests available, the enzyme linked immunosorbent assay ELISA is widely recommended for epidemiological studies (BOSSAERT et al, 2000).…”

“…Serological tests for the diagnosis of infection by F. hepatica were developed (SANCHEZ-ANDRADE et al, 2000) and are an alternative diagnostic to indirect methods of assessing the effectiveness of control methods. The advantages of the serological analysis are outstanding, since early chemical intervention reduces tissue damage caused by the migration of immature stages of the parasite and the fecal excretion of eggs by the hosts (MOLLOY et al, 2005).…”

Distribution of Fasciola hepatica in Swedish dairy cattle and associations with pasture management factors

“…Although the sensitivity of BTM-ELISA is considered to be lower than that of ELISA based on serum and/or individual milk samples (Duscher et al, 2011), a high positive correlation between F. hepatica-specific BTM antibody levels and herd seroprevalence has been demonstrated (SalimiBejestani et al, 2005). Minimum in-herd prevalence in flocks for F. hepatica antibodies to be detectable in BTM samples varies from 20% to 60% (Reichel et al, 2005;Salimi-Bejestani et al, 2005;Duscher et al, 2011).…”

Herd-level prevalence of selected endemic infectious diseases of dairy cows in Great Britain

“…In addition to these ongoing recording systems, oneoff surveys are often carried out (Davison et al, 2005;Salimi-Bejestani et al, 2005;Woodbine et al, 2009b); although useful, their results should be interpreted with caution because of issues such as nonprobabilistic selection of studied farms (Paton et al, 1998;Woodbine et al, 2009b;Williams and Winden, 2014) and failure to adjust prevalence estimates for the study design (Paton et al, 1998) or for test performance (Davison et al, 2005;Woodbine et al, 2009a;Williams and Winden, 2014). Furthermore, one-off studies are only useful for a limited period of time, as the prevalence can change as a result of the implementation of control measures and changes in the dairy industry, the more apparent of which are increased herd size, genetic selection, and application of new technological innovations (Barkema et al, 2015).…”