premise: Two Egyptians were taken to hospital Saturday after testing positive for the deadly H5N1 strain of bird flu in the central Nile delta region, the health ministry said.
  The latest cases brings to 17 the total number of Egyptians infected, including seven who were killed by the virus.
  The two Egyptians from the village of Hanut in the Gharbiya governorate contracted the disease after coming into contact with infected ducks they had been rearing in their homes, according to a ministry statement carried by the official MENA agency.
  All the birds in the house and in neighbouring homes were slaughtered and the area disinfected, MENA said.
  Egypt -- the Arab world's most populous state -- is on a major route for migratory birds and has seen the third highest number of H5N1 cases after Indonesia and China according to Dr David Nabarro, the UN official charged with battling bird flu.
   What can happen if a person is infected by the virus?
hypothesis: coming into contact with infected ducks