Turkey ? The World Health Organization, eager to get a better understanding of the deadly bird flu strain spreading across Turkey, said Friday it has asked the government for permission to send teams into villages to take blood samples, swab throats and interview families.

Gueneal Rodier, a communicable diseases expert at the U.N. agency, told The Associated Press that WHO is particularly keen to investigate whether the virus is mutating into a form that could become easily transmissible from person to person.

So far, health experts have focused on 18 cases in Turkey of people confirmed to be infected with the deadly H5N1 strain and on others hospitalized with flu-like symptoms. Among the 18 cases confirmed by Turkish authorities, three were siblings who died last week.

The three were the first known deaths from the virus outside of East Asia, where at least 77 have been killed by an outbreak of bird flu since 2003. The WHO said Friday that a 29-year-old Indonesian woman who died this week had tested positive for bird flu, bringing its toll worldwide to at least 79 people. WHO has so far only confirmed two out of the three deaths in Turkey were from the H5N1 strain.