AUGUST 6 2008 19:52h
`They have bird flu symptoms such as fever and breathing difficulties,` Ginting was quoted as saying.
Sinar Ginting, a spokesman for the Adam Malik hospital in North Sumatra's capital Medan, was quoted by Kompas.com as saying that two patients from the group had been transferred to the hospital early on Wednesday morning.
The other 11 from Air Batu village were being treated in a local hospital, he said.
"They have bird flu symptoms such as fever and breathing difficulties," Ginting was quoted as saying.
Not all the patients were believed to have had contact with fowl, which is the most common way of contracting the virus, but Ginting said some chickens in the area had died suddenly and were found to have had the deadly H5N1 virus.
Indonesian health ministry officials could not immediately be reached for comment.
The Southeast Asian country has had 111 confirmed human bird flu deaths, the highest in the world.
Suspected cluster cases happening in the same vicinity can raise concerns about rare human-to-human transmission.
Although bird flu remains mainly an animal disease, experts fear the H5N1 virus might mutate into a form easily passed between humans, causing a pandemic.