Ireland bovine tuberculosis reactor numbers drop despite local surges

Mid-Year Figures and the Shift in Blood Testing Strategies

Earlier this year, Department of Agriculture statistics delivered an encouraging drop in bovine tuberculosis numbers. Figures published at mid-year recorded a 20% decrease in reactors removed in the 12 months up to the end of June compared to the same period in 2025, accounting for 34,886 reactors. Farmers received warnings that numbers would likely tick upward again as authorities deployed targeted blood testing for larger herd breakdowns. This diagnostic shift aimed to catch infected cattle earlier than standard skin tests permit. Newly released Department figures indicate that the 12-month total through August rose slightly to 35,569 reactors, though this count remains markedly below the levels recorded at the same stage in 2025.

Worsening Disease Hotspots in Wicklow and Louth

While national totals show an overall year-on-year reduction, several counties face escalating caseloads. Comparing the 12 months leading to August against August 2025 data reveals rising reactor numbers in Carlow, Donegal, Kildare, Laois, Limerick, Wexford, Wicklow, and north Cork. Furthermore, 12-month herd incidence increased in Carlow, Donegal, Kildare, Tipperary, Louth, Wexford, Wicklow, and Roscommon.

County Wicklow remains a primary disease hotspot. In the western part of the county, over one in five previously clear herds went down with the disease over the past year. This drove a 52% surge in reactor removals, climbing from 829 to 1,260 head. Eastern Wicklow saw reactors increase by 34% to 1,349, with herd incidence reaching 11.8% by the end of August. County Louth recorded the largest proportional jump nationwide, as herd incidence climbed to nearly 9.71% from 6.80%, accompanied by a more than 25% increase in reactor numbers.

Diverging Fortunes Across Tipperary

County Tipperary experienced starkly contrasting trends between its northern and southern districts. The north of the county drove herd incidence below 6%, while reactor numbers plummeted from over 2,600 head in the previous 12-month period to 1,400 head this year. Conversely, the south of the county saw herd incidence worsen to 8.11%, with reactor numbers rising 9% to 2,278.

Notable Improvements in Western and Southern Counties

Several regions recorded substantial progress against the disease. Galway closed out August with a 12-month herd incidence of 2.89% and a greater than 40% drop in reactor removals, falling to 1,381 head. County Sligo also reined in infection levels, dropping its herd incidence to 3.24% and almost halving its reactor count compared to 2025 figures.

County Leitrim extended its low infection rates, recording a herd incidence of 2.81% by the end of August while cutting reactor numbers by nearly half to 261. In south Cork, reactor numbers dropped by over a third to 1,523, accompanied by a herd incidence rate of 4.76%, marking a sharp improvement from the 3,238 reactors and 7.30% incidence recorded a year earlier.

Frequently Asked Questions

What is the difference between reactor removals and herd incidence?

Herd incidence measures the percentage of previously clear herds that test positive for the disease over a 12-month period.

Why did Department of Agriculture officials expect an uptick in TB numbers?

Authorities anticipated a rise due to an increased operational focus on blood testing during larger herd breakdowns, designed to identify infected cattle at an earlier stage than standard skin tests allow.

Which counties recorded the largest increases in herd incidence?

County Louth experienced the largest proportional jump, with herd incidence rising to nearly 9.71%, while counties including Wicklow, Carlow, Donegal, Kildare, Tipperary, Wexford, and Roscommon also saw incidence rates increase.