This is very common cause for blur vision,
Botulism 320 (sq 1655 8500 2324-1 4585 5196-8 6876-2 7124-2 9920) Hz
This set of frequencies has been updated with square wave non aliased.
This disease looking like big jaws at the side of the face,
Parotitis, Epidemic 130 300 830 2500 7500 (sq 2250 1420-2 2510-2 3255-8 4718-7) Hz
can also affect vision.
Grippe was another name for flu, now no longing in common use,
Grippe 80 250 570 7500 (sq 1053 1250 4000 3133-5 3200 6150) Hz
The scary thing is, the runny nose, sore throat.. go away but the virus remains to attack the kidneys, lungs, brain, etc.
Good grief.