The shortage of rabies vaccines was a very serious thing a few years ago, but was rumored to have been remedied. Used to have monthly meetings with our dept. of health and others in my old job and thought this issue was at least a few years old. I'd recommend anyone in this field have a doctor that understands your work, your exposures and risks and tests you for appropriate respiratory and other issues on a yearly basis. Realizing many don't have health insurance and that many will just be hoping that something bad doesn't happen.
Rabies shots can give you a strong titer for up to a decade or longer, I know many who have reported this in my old job where we were tested routinely. However, it is important to have them checked and your doctor should be able to tell you how often as CDC and others provide info to the medical community, whether they stay up to speed is much the same as any industry, don't expect all doctors to be up to date on the latest in zoonotic risks.
Also, it seems the take home message from most on the above thread, is check with your state or county health dept. No one wants you to be a statistic and when you explain that you work with wildlife daily in close quarters, you shouldn't get any resistance to you needing shots, or to check your titer.
Here is a link from the AVMA (on how often to have titer checked) to use as a bit of a reference, but again, find a good doc!
https://www.avma.org/News/JAVMANews/Pages/101001p.aspxJustin