The bovine tuberculosis cluster in north County Sligo during 2014–16

Table 1 Number (%) of bTB restrictions, by restriction severity and risk classification of the breakdown test. Herds within the study area were determined based on the District Electoral Division of the herd number

Risk classification of the breakdown test	Restriction severity (Number of SICTT^a reactors/animals with bTB lesions at slaughter)			Total
Risk classification of the breakdown test	1	2–3	≥4	Total
Low-risk ^b	14 (51.9)^c	9 (33.3)^c	4 (14.8)^c	27 (37.5)^d
High-risk ^e	16 (35.6)^f	10 (22.2)^f	19 (42.2)^f	45 (62.5)^d
Total	30 (41.7)^d	19 (26.4)^d	23 (31.9)^d	72

^aSingle intradermal comparative tuberculin test
^bThe initial breakdown test was classified as ‘low-risk’ if conducted on unrestricted ‘low’ risk herds. All unrestricted ‘low’ risk herds are tested annually with single intradermal comparative tuberculin tests (SICTT) conducted on all animals > 6 weeks of age (the annual test; test type [TT] 1)
^c% of restrictions that were first detected with a low-risk test
^d% of all restrictions
^eAll other breakdown tests using SICTTs were defined as ‘high risk’ tests, including inconclusive retests (TT3), contiguous (TT8), high risk (TT5A/F), post de-restriction (TT7B) and factory lesion tests (TT9A and TT10A; that is, following detection of a factory lesion during abattoir surveillance)
^f% of restrictions that were first detected with a high-risk test

ISSN: 2046-0481