There's no reason to expect any parallels between variolation with these two unrelated viruses.
> The most directly relevant data is on SARS[2] and measles[3], where natural differences in doses were associated with factors of 3 and 14 in death rates, and[4] in[5] smallpox, where in the 1700s low “variolation” doses given on purpose cut death rates by a factor of 10 to 30.
It looks like the initial dose size has a huge impact on mortality for a wide range of diseases.
1. http://www.overcomingbias.com/2020/03/variolation-may-cut-co...
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3367618/
3. https://pubmed.ncbi.nlm.nih.gov/3723239/
4. https://www.nlm.nih.gov/exhibition/smallpox/sp_variolation.h...
5. https://www.npr.org/sections/goatsandsoda/2018/02/01/5823701...