Health experts in an Indonesian village hit by an unprecedented bird flu outbreak have asked more than 30 people to quarantine themselves to contain any potential further spread, officials said yesterday.
People who had close contact with any of seven relatives who have died since last month in the North Sumatran village are being monitored for signs of illness, WHO spokesman Dick Thompson said.
“The focus right now is contact tracing, identifying those people who may have been in contact with this cluster,” Thompson said in a telephone interview.
“We will monitor their health and encourage them to self-quarantine themselves,” he said.
A day after another WHO spokesman, Peter Cordingley, said the UN body was “stumped” about the original source of the infection, Thompson said that contact with an infected bird was now considered the likely cause.
Cordingley also on Wednesday described the outbreak as “the mother of all clusters.”
One of the scientists’ concerns is that the virus may have spread to a third generation, where one person infects another who in turn infects another.
If that were the case, it would be the longest chain so far recorded. Previous suspected human-to-human cases have stopped with one person infecting one other in close contact.
But Thompson stressed that there was evidence that the virus had not mutated into a form that could be more easily spread from humans to humans.
“From what we see it takes very close and maybe prolonged contact with a sick individual,” he said.
Thompson said that while Indonesia’s cluster was the biggest so far, there had been “maybe four to five” close-contact infections since the latest outbreak of bird flu in late 2003. Since then 124 people in nine countries worldwide have died, 33 of them in Indonesia.
“It’s a very hard thing to say with absolute certainty,” he said about establishing proof of human-to-human infections.
He said samples of the virus taken from the cluster of victims had been sequenced in a Hong Kong laboratory and had not shown any signs of mutation into a more contagious form.
Indonesian Health Minister Siti Fadilah Supari denied that human-to-human transmission had occurred in the Sumatra cases.
“I reject this assumption. The virus has not passed between humans,” she told Detikcom news portal by telephone from Singapore.
“There’s no epidemiological evidence pointing to human-to-human transmission,” she said.
The WHO has sent a 10-member team to Kubu Simbelang village in Karo district to identify those who had close contact with the family. So far more than 30 people, including more relatives, have been traced and have been asked to quarantine themselves.
“We will monitor them for a week or two to see if they become sick. if they do they will immediately be put in isolation in a hospital,” Thompson said.
He said that the group under watch might be given Tamiflu, a drug that has shown to have some effectiveness in reducing the mortality rate of avian flu when administered early on.
Bird flu tests would be carried out on anyone who showed signs of sickness.
Six people in the family have been confirmed to have been infected with H5N1.
The WHO has concluded that the first person in the family to die was also a bird flu victim although she was buried before tests could be carried out.
The cases have brought Indonesia’s bird flu death toll to 33, with 22 of those this year.