Roman wine / would the mix really kill germs?

Factual Questions
1

It’s said in most of the Roman dock-dramas that the Romans used to mix red wine 1/3 with water partly because the alcohol made the 2/3 water safe to drink. Really? Thats a pretty dilute solution only about 4 percent alcohol? If I mix Roman style wine in say Thailand where the tap water is not safe to drink, is it safe to use the water from the tap to dilute red wine 2/3 then drink it? Is that 4 percent alcohol enough to kill the nasties and does it do it quickly enough that you can mix the wine and drink it straight away or would you have to let it sit for a period?

(I am actually in Thailand right now, but no Don’t need answer fast, I was curious if it would be safe).

2

Previous thread.

If you dilute it and leave it for a while, then yes, it will kill bacteria in water. There is a reference here to work done at the Pasteur Institute which established that dilute red wine kills typhus in four hours.

3

And a drop of vineger for flavor.

4

Right, and I’m pretty sure I have read that the romans DID in fact used to mix their wine then let it sit for a number of hours.