A “marked increase” has been noted in the national herd incidence for bovine TB (bTB) for the first three months of 2020, according to the latest figures from the Department of Agriculture, Food and the Marine.

In an update this week, the department noted that, on Sunday, March 29, national herd incidence for bovine TB stood at 3.26% for the year to date, up from the 2.64% that was recorded for the same period in 2019.

It was noted that from Wednesday, January 1, to Sunday, March 20, 3.26% – working out as 853 of 26,164 herds tested for TB so far – have had at least one animal test positive.

This is an increase of about 23%, the authority said.

This continues the trend of a gradual ongoing increase in bTB incidence in Ireland in recent years, the department warns.

“While levels are still considerably lower compared to pre-2013, it is clear that further efforts are needed by all stakeholders to arrest and reverse this recent pattern,” the department said.

Map and county breakdown

While bTB levels in many areas overall are low, there are areas with higher levels of bTB in the north-east of Ireland – namely Monaghan, Cavan, Louth and north Meath, as well as parts of Clare, Cork, Wicklow and some other districts, the department highlights.

The number of reactors identified through a combination of skin testing and gamma interferon blood testing (GIF) for the first quarter of 2020 was 4,276.

This is an increase of 1,413 reactors when compared to the first three months of 2019, up approximately 49%.

“Rising herd incidence and reactor numbers are of concern to all stakeholders,” the department said in a statement.

“Senior Department of Agriculture officials at policy and operational level are closely reviewing national and regional trends in order to determine the main factors influencing these changes,” the department stressed.

Image source: Department of Agriculture, Food and the Marine

Image source: Department of Agriculture, Food and the Marine

“Continuing cooperation between farmers, private veterinary practitioners and department officials will be required to take action to reduce disease spread and target more effectively the high-risk factors associated with bTB transmission in order to bring disease trends back on a downward trajectory.

To tackle this, a targeted, high-impact bTB control plan is in place in Monaghan and parts of Cavan and Clare, which has been implemented in collaboration with stakeholders, the authority said.

In a breakdown of the figures, it was noted that Wicklow West, Wicklow East and Dublin have the highest herd incidence when compared to the national average of 3.26%.

However, these regions combined represent 1.7% of the national herd, it was noted.

On the other end of the scale, Waterford and Limerick had the lowest herd incidence at 1.22% and 1.75% respectively.