Used to be mandatory, but we're talking decades ago. After the breakup of USSR, many republics went back to MIddle Ages, mostly due to finances, and many being moslem on top of that.
As much as I am not a fan of Russia's health industry, for many reasons, one thing they do right, IMO, is how they approach vaccinations. In addition to what we get here, they vaccinate against some other medical issues, including Hep B, I think. And also vaccinate for certain things every 25-30 years as they claim a body needs to be re-vaccinated again after a period.