Nope. The amount of water in alcohol doesn't affect it's ability to kill germs at all.
If you are using, for example, 20% alcohol, it is as effective as 1/5 of the 100% alcohol. Just use more of it.
Actually, just washing things down with water and a bit of soap is just as effective for practical cases. While it doesn't destroy the virus, it does remove it. Just put it the sewer. If the water is hot enough, it will destroy the virus, even without soap.
Another way to destroy the virus is to expose it to UV light, such as that contained in sunlight. UV-A is sufficient to destroy the virus. Sunlamps also work, but UV LED devices are generally not going to do much, due to their low power.
My bad. isopropyl alcohol does not go that low. It begins at the 70% level.
Ethyl @ at least 60% and Isopropyl @ at least 70% will kill viruses, funguses & bacteria, but only the 70% level of Isopropyl will kill the spores.
Play it safe and always opt for the 91% and 99% Isopropyl.
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