I live in British Columbia and it is well known that, in the late 19th century, there was a massive crash of the native population. Up to 90% in some particularly unfortunate areas (Haida Gwaii, for example). A lot of this was due to smallpox.
I'm aware of the timeline of early Western medicine, around Pasteur and Koch, so I always assumed that, whatever the intentions were on the US, British and Canadian side, there wasn't much that they could have done about it, had they chosen to help.
However, on visiting Maui, I was extremely surprised to see that some of the missionaries there, around 1865, were trying to vaccinate the Hawaiians against smallpox. Looking it up https://en.wikipedia.org/wiki/Smallpox_vaccine, it turns out that smallpox was atypical as it was known, even with limitations of Western medicine at the time, that you could take steps to protect populations at risk.
Hawaii aside, when did large-scale effort start, in either the US or in Canada, past the 1850s or so, to inoculate native New Worlders using what was then known about smallpox vaccination?
Just to be clear, this is not a question about intentional contamination, such as blankets issued for that purpose. Or even an episode such as www.macleans.ca.how-a-smallpox-epidemic-forged-modern-british-columbia/ , where it might (or not) have suited the authorities to have an epidemic.