IIRC, most plagues take off, due to the unsanitary conditions. Similiar to the AIDS/HIV epidemics.
You are comparing apples and oranges.
Plague is a bacterium. You are correct in assuming that proper sanitation gives some measure of protection against the bubonic bacterium. But, by no means, does it give complete protection. For example, the normal transmission vector for plague is rodent to flea to human. However, if the plague converts to the pulmonary form, all bets are off. The vector is then directly from human to human. Even in the absence of the pulmonary form, do you really want to bet your life that you can avoid all fleas? Are you going to kill all your pets?
The smallpox pox virus? You can be as clean as possible. Sterilize your sheets. Mop with boiling water. Sterilize your dinnerware. Spray DDT in layers on your property. The smallpox virus won't care. Not to say that boiling your sheets and dinnerware would not kill the virus...it just would not do enough to prevent infection.
This is the downside of not getting vaccinated to avoid the vanishingly small probability of serious reactions. Out of each ten of your family members, nine will become infected. Three of the nine will die. Six will live. (Remember this is the AVERAGE, if you're not lucky, your entire family might die) So your post smallpox epidemic family will look like this: There will be seven family members where there were once ten. Of the seven, six will have horrible and permanent scarring over their entire bodies...including their faces.
So, you're going to take your family and retreat into the mountain or desert to avoid the epidemic. Got a problem, guy. HIV virus dies in minutes in the open air. Hepatitis can survive for hours. Smallpox virii will survive for years or decades. You're going to be totally isolated in the mountain or desert for a very long time to be safe. In fact, children born there will be adults before they can safely meet outsiders. I hope you don't have problems with inbreeding.
Check out the probability of a serious reaction with the vaccination. Compare it with the infection and fatality rates for small pox. Make up your own mind as to the greater risk.
Now, personally, I don't think the government is being totally honest with us. Several weeks ago, I walked into the trauma room in the emergency department where I work. There was a new addition...a 3'X3' poster with color pictures taking you step by step in both the diagnosis of smallpox and the differentiation between smallpox and other poxes such as chickenpox. The conclusion I have drawn from this is: 1)either the government is playing CYA in the extremely unlikely event of a smallpox attack or 2) the government has received reliable intelligence pointing to the possibility of such an attack and is concealing it to protect "nation intelligence means and methods."
In view of the chaos in Russia during the past 13 years, I'm not willing to discount the second possibility. Are you willing to bet your life and the lives of your loved ones? Because that is exactly what you could be doing.
The CDC currently believes that the smallpox vaccination confers immunity for about ten years.