Besides, according to these statistics 60% of children/adults and 90% of the elderly should be dying of smoking related diseases right now by your assumption:
Cytomegalovirus - Wikipedia, the free encyclopedia
"58.9% of individuals aged 6 and older are infected with CMV while 90.8% of individuals aged 80 and older are positive for HCMV"
People ARE dying from CMV! Even your Wickipedia page admits that "CMV seems to have a large impact on immune parameters in later life and may contribute to increased morbidity and eventual mortality." And the quacks with lifestyle questionnaires are either blaming whatever's politically correct or incorrect with the privileged class (who are less likely to have CMV), or just saying they don't know.
http://www.smokershistory.com/CMVimmun.html