could be, i think the last flu attack partly came from the water here, might of been a different virus then what the vacs were spreading
years ago i learned, no harmful virus is small then one micron, so if you have a filter that goes down that low, might be good thing to have, city water should be filtered anyway
now, that one micron was years ago that i read from a very reliable source (of whom i cant not say without a doxing rabbit hole), and maybe one micron was all natural viruses,
i dont know about man made ones if they can make a harmful one smaller then one micron