Soviet apartments had a separate rooms for the toilet and the area with a bath/shower/sink. The area behind the toilet was usually a hinged wall that could be opened to reveal the entry point for utilities.

I assume toilet hands were an unspoken issue, because there was no possible way to traverse from the toilet room to the washroom without touching anything.

For a complete tangent, I’ll mention that Soviet toilets had a “poop shelf” so that people could eyeball their stool to gauge their health. One flaw of this design is that there was no odour suppression offered by toilets that immediately immerse stool in water.