HL Deb 09 March 1998 vol 587 cc4-6WA
The Countess of Mar

asked Her Majesty's Government:

What was the distribution of age at diagnosis of, and death from, BSE:

  1. (a) at the height of the epidemic; and
  2. (b) for the last six months of 1997
for England, Scotland, Wales and Northern Ireland; whether the incubation period of this disease is inversely related to the dose of the agent which initiates the infection; and whether there is any trend indicating that the dose initiating the infection is considerably reduced in the most recent data. [HL793]

Lord Donoughue

The following tables show the distribution of known age cases by their age at clinical onset of BSE for cases reported in 1992 and 1993, when the epidemic was at its peak, and for the last six months of 1997.

1992
Age England Wales Scotland Northern Ireland
1 1 0 0 0
2 26 1 1 1
3 1,401 156 66 39
4 10,544 1,073 547 140
5 7,119 707 308 127
6 2,264 214 91 47
7 670 55 23 18
8 276 19 4 0
9 103 3 2 2
10 14 3 0 1
11 12 0 0 0
12 4 0 0 0
13 0 0 0 0
14 2 0 0 0
Total 22,436 2,231 1,042 375

1993
Age England Wales Scotland Northern Ireland
1 0 0 0 0
2 14 3 0 1
3 874 103 46 6
4 5,070 518 283 90
5 9,653 1,049 685 225
6 4,031 463 221 96
7 934 102 53 25
8 322 23 13 8
9 124 12 6 2
10 52 2 4 1
11 15 1 2 1
12 4 0 0 1
13 1 0 0 2
14 0 0 0 1
15 0 0 0 0
16 0 0 0 1
Total 21,094 2,276 1,313 480

July to December 1997
Age England Wales Scotland Northern Ireland
1 0 0 0 0
2 1 0 0 0
3 53 2 1 0
4 314 25 6 6
5 455 47 14 3
6 273 28 9 1
7 157 12 7 1
8 95 7 8 0
9 52 3 2 0
10 24 1 2 0
11 7 1 0 0
12 1 0 0 0
13 0 0 1 0
14 1 0 0 0
Total 1,433 126 50 11

Note:

For the last six months of 1997 GB figures are preliminary. As at 27/2/97 over 250 results were outstanding. NI figures are complete.

The incubation period of field cases of BSE is not known as the date of exposure to the disease agent is not known. In experimental studies of transmissible spongiform encephalopathy agents there is an indication that lower doses result in longer incubation periods, but the relationship is not exact.