The Soviet Union had the highest physician/patient ratio in the world. USSR had 42 doctors per 10,000 population compared to 24 in Denmark and Sweden, and 19 in US:
https://sci-hub.se/http://www.sciencedirect.com/science/article/pii/0735675784900482
USSR defeated a smallpox epidemic in a matter of 19 days
https://www.rbth.com/history/331857-how-ussr-defeated-black-smallpox