NO not always. Some varieties are resistant.

"Wilt" is not contagious. There is a very large body of thought that contends that wilt is not a disease or fungal issue at all but rather the inability of the vine (through insufficient root mass or stem diameter) to support the considerable top growth. The fact that clematis wilt is seldom ever fatal and that most vines outgrow it after several years seems to support that contention.

Highly hybridized clematis - generally most of those that are included in the pruning group 2, like your 'Ernie' - are most prone to wilt and species clems or those very close to species are most resistant. If you have concerns, select from pruning group 3's or one of the viticellas or viticella hybrids. And if one were to plant a new vine prone to this problem (any group 2's) deeply enough in a well prepared planting hole and prunes hard for the first couple of seasons to encourage root and good stem development, you may never experience any wilt at all.

Ditto to what Gardengal said. Try growing the type IIIs to minimize the issue of wilt.

Thank you all for your posts! Other than Ernie and Nelly Moser I don't have any Type 2s and have avoided them for this exact reason. I almost ordered some yesterday but decided to stick with the Type 3s. I was just concerned that wilt might transfer by contact even to a Type 3 but I'm glad to read the information you have all posted. I am not very experienced with Clematis when it comes to some of these issues. Thanks!
Kim