Schistosomiasis (also known as Bilharzia, snail fever, or Katayama fever) is caused by flatworm parasites that live in the blood vessels of the bladder and intestines. Schistosomiasis - also known as bilharzia, snail fever, or Katayama fever - is caused by flatworm parasites that live in the blood vessels of the bladder and intestines. Health Matters
A Tornado warning means A tornado has been  spotted/touched down in your alert area. You should take  cover if a tornado warning is issued for your area;  go into a cellar, or the lowest, most inner part of your house  where there are no windows (a downstairs or basement bathroom is  ideal).
The key is whether your family would know where to go and what to do. when the big one potentially hits. Paul Shipman, of the American Red Cross, says that no matter how you get a severe weather warning -- from television, the radio or your smart phone or tablet -- itâs time to spring into action once you see a tornado warning.