I've gone an entire year without showering or bathing properly. Why? Well, this was after I was diagnosed with Kidney failure, and I had a catheter in my chest for dialysis. I was told that I could not get it wet at all, so while I had my catheter I avoided showering and bathing. I did kept myself clean by using a sponge to wash myself and dipped my head under the bathtub faucet to wash my hair. Since I've got rid of the catheter, I take showers more regularly. Longest I've gone without a shower has been several days though, sometimes a week if I'm lazy. *shrugs*