Table 1.

Diversity of meningococci isolated from invasive disease over 20 years in England and Wales

	Number
	1975	1985	1995
Isolates	125	100	100
Sequence typed	123	100	100
Strain types	67	70	79
Serogroups	4	4	4
PorA VR1 variants	15	18	13*
PorA VR2 variants	20	25	21
FetA VR variants	23	19	22
STs	48	55	52
Clonal complexes	13	18	11
Isolates not assigned to a complex	4	5	6

*Including one isolate with a stop codon in VR1.