Bovine TB: Gamma interferon testing in Great Britain – monitoring data
The tables below present monitoring data of gamma interferon (g-IFN) testing in Great Britain since the use of the g-IFN test was extended on 23 October 2006 as part of a new policy designed to improve the testing of cattle for bovine TB.
Gamma interferon testing in Great Britain: 1 January - 31 August 2008
Type of Test |
|
England |
Scotland |
Wales |
GB Total |
Parallel |
Number of herds sampled |
723 |
36 |
384 |
1,143 |
Number of animals sampled |
9,688 |
2,843 |
2,658 |
15,189 |
|
Number of samples positive to g-IFN test |
1,957 |
284 |
784 |
3,025 |
|
% of samples positive to g-IFN test |
20.2% |
10% |
29.5% |
19.9% |
|
Samples for which no result obtained |
412 |
246 |
96 |
754 |
|
|
|
|
|
|
|
Serial |
Number of herds sampled |
4 |
0 |
5 |
9 |
Number of animals sampled |
74 |
0 |
27 |
101 |
|
Number of samples positive to g-IFN test |
4 |
0 |
0 |
4 |
|
% of samples positive to g-IFN test |
5.4% |
0% |
0% |
4% |
|
Samples for which no result obtained |
1 |
0 |
1 |
2 |
Gamma interferon testing in Great Britain: 23 October 2006 – 31 December 2007
- 1 January – 31 December 2007
(10 KB) - 23 October – 31 December 2006 (15 KB)
Note:
- All data is provided by the Veterinary Laboratories Agency (VLA) and is provisional, subject to change as more data becomes available;
- Cumulative data for 2008 will be reviewed and updated monthly;
- Parallel testing is designed to improve the sensitivity of diagnosis, whereas serial testing is designed to improve the specificity of diagnosis. The type of test used depends on the situation in question, in line with the prescribed circumstances for mandatory testing;
- Differences in positive rates between areas is likely to represent variations in the reasons for usage and different risks/disease prevalence between the various categories of animals to be tested;
- * Samples that fail VLA's stringent quality controls and do not give a reliable result, or that are unsuitable for testing when first submitted to the laboratory. In these cases, a resample is requested for the same animal, resulting in a new g-IFN test being added to the cumulative statistics. The original number of rejected blood samples has been recorded in this table, even if the animals in question were eventually resampled and yielded a positive or negative g-IFN test result.
Gamma interferon testing in Great Britain before 23 October 2006
Further detailed data on g-IFN testing carried out before 2006 is available in the following reports:
- Gamma interferon field trial (November 2002 - October 2005) (857 KB)
- Gamma interferon specificity trial (335 KB)
Page last modified:
10 October, 2008