Thanks, hedgehog. It's interesting: there's talk of the autistic spectrum, but in quotes which imply it's a new thing, in (Wing, 1993), but no mention of a spectrum in (Wing and Gould, 1979). The concept is presumably in (Wing 1988). (Einsenmajer et al, 1996) refer in passing to "autistic spectrum" in their last paragraph, which in turn cites (Wing, 1991) which I think is the chapter you're referring to as picking up Asperger's works. Wing writes about it in a book again in (Wing, 1996).
So my gut feel is that the concept of a spectrum emerged 1988-1991, but wasn't named until the mid-1990s. Wakefield publishes in 1998. So I stand by my contention that in 1998 the typical parent on the Clapham omnibus hadn't heard of the autistic spectrum, hadn't heard of Asperger's as a form of autism (or, probably, at all), but had heard of regressive, non-commnicative autism. Hence the scare: for people who didn't read the literature and didn't have access to a medical library (and I've just pulled up half a dozen medical papers from my office desk: imagine doing that in 1996 with a university ID card and a morning in a medschool) autism just mean Very Scary Bad Thing You Do Not Want.
Eisenmajer, R., Prior, M., Leekam, S., Wing, L., Gould, J., Welham, M. and Ong, B., 1996. Comparison of clinical symptoms in autism and Asperger's disorder. Journal of the American Academy of Child & Adolescent Psychiatry, 35(11), pp.1523-1531.
Wing, L., 1991. The relationship between Asperger’s syndrome and Kanner’s autism. Autism and Asperger syndrome, pp.93-121.
Wing, L., 1993. The definition and prevalence of autism: a review. European child & adolescent psychiatry, 2(1), pp.61-74.
Wing, L., 1988. The continuum of autistic characteristics (pp. 91-110). Springer US.
Wing, L. and Gould, J., 1979. Severe impairments of social interaction and associated abnormalities in children: Epidemiology and classification. Journal of autism and developmental disorders, 9(1), pp.11-29.
Wing, L., 1996. The autistic spectrum: A guide for parents and professionals. Constable.
Wing, L., 1997. The autistic spectrum. The lancet, 350(9093), pp.1761-1766.