Map: ‘Marginal’ increase in national TB statistics for 2018

National herd incidence for bovine TB stood at 3.51% as of December 31, 2018, marginally up on 2017, according to the Department of Agriculture, Food and the Marine.

This means that since the beginning of 2018, of all the herds tested for TB, 3.51% have experienced a new breakdown, i.e., they have had at least one animal that tested positive for TB.

While TB is at historically low levels, progress towards eradication appears to have slowed since 2015, according to the department.

As the following map shows, TB levels overall are at a low level but there has been a relatively high level of TB concentrated in the north-east of Ireland throughout 2018 – i.e. Monaghan, Cavan, and north-Meath.

Source: Department of Agriculture, Food and the Marine

At a national level, the number of herds in Ireland was 112,105 representing a decrease of 1,592 – some 1.4% – relative to 2017.

During 2018, 3,874 herds experienced a restriction. As of the end of December 2018, there were 2,176 herds restricted. Both of these figures were broadly unchanged from 2017, according to the department.

Herd incidence in 2018 was 3.51%. While TB levels remain at historically low levels, herd incidence in 2018 was nonetheless similar to levels in 2014.

The number of reactors identified in 2018 was 17,491. This is the highest number of reactors since 2012. The increased use of Gamma Interferon (GIF) blood testing, however, has been a significant factor in higher reactor numbers over the past few years.

In 2018, GIF testing accounted for over 20% of reactors.

Regional incidences

The herd incidence in Monaghan of 8.91% and Cork North of 5.66% (which is significantly higher than the national herd incidence of 3.51%) are particularly relevant as they have higher cattle densities than other counties and this therefore indicates greater amounts of TB, according to the department.

Cork North had the highest number of reactors at 2,086; Monaghan had the second highest at 1,677 followed by Tipperary North with 1,296 reactors.

A targeted TB control plan has been in place in Monaghan during 2018 in collaboration with stakeholders. Its focus is to identify and eradicate disease in that area as quickly as possible.

While Wicklow East had the highest herd incidence at 9.51% – some 596 reactors – this region has less than 1% of the national herd, according to the department.

Donegal and Limerick had the lowest herd incidence at 1.70% and 1.79% respectively.