Jul 15, 2005 (CIDRAP News) – An Indonesian man and his two young daughters have died of suspected avian influenza, triggering alarm about possible person-to-person transmission of the H5N1 virus.

If the cases are confirmed to be avian flu, they will mark the first symptomatic human cases and first deaths in Indonesia. The island nation has had intermittent poultry outbreaks and one asymptomatic human case, reported last month. H5N1 infections in pigs have also been reported there.

The victims were a 38-year-old man and his daughters, aged 1 and 9 years, according to an Associated Press (AP) report today. They lived in a suburb of Jakarta and had had no known contact with poultry, Indonesian Health Minister Siti Fadilah Supari told reporters.

"These are suspected bird flu cases," Supari was quoted as saying at a news conference. "We have sent specimens to Hong Kong to confirm the [test] results, which will take seven to 10 days."

The three victims died within the past week and a half. Supari said one daughter died first and was not tested for avian flu. The father, named Iwan Siswara Rifei, died Jul 12, and the second daughter died Jul 14, according to an Agence France-Presse (AFP) report. Both were tested for avian flu, a Reuters report said.

Earlier this week, Indonesian officials had denied that the deaths were linked to avian flu. Supari blamed the first two deaths on acute bacterial pneumonia in a statement reported Jul 13 by the Chinese news service Xinhua.

"The first test showed negative for the H5N1 virus, then we conducted a second test, which showed signs of the H5N1 virus," Reuters quoted Supari as saying today. But she said there was some doubt about the results, prompting the decision to send samples to Hong Kong for confirmation.

Supari said there was concern about possible human-to-human transmission because there was no evidence the victims had contact with poultry, Reuters reported.

Rifei"e;s widow, their son, and the family"e;s two maids have shown no signs of illness, the AP reported. Authorities were testing blood samples taken from 315 people who had contact with the family, reports said.

The AP quoted a World Health Organization (WHO) official, Dr. Georg Petersen, as saying that further investigation could reveal that the victims did have contact with poultry. "In other countries, this is often the case," he said.

The virus has not yet shown any consistent ability to spread from person to person. Experts concluded that the virus probably passed directly from a 11-year-old Thai girl to her mother and an aunt in September 2004, and some family clusters in Vietnam this year raised suspicions of person-to-person spread.

But a team of international experts who studied H5N1 samples in Vietnam last month reported in late June that the virus had not improved its ability to spread among humans. The WHO cautioned at the time, however, that the risk of a human flu pandemic was still serious.

The only previous human case of H5N1 avian flu in Indonesia involved a poultry worker who was tested last March, though he had never been sick. He was found to have a low level of antibodies to the virus, according to results reported in June.

Indonesia has had a number of H5N1 outbreaks in poultry, going as far back as August 2003. In May of this year, some pigs on the island of Java were found to have asymptomatic H5N1 infections. The pigs lived near poultry farms that had been hit by the virus. Pigs are often described as a mixing vessel in which avian and human flu viruses could exchange genes, potentially spawning a new virus that could spark a human pandemic.