Thursday, May 25, 2006

H5N1: "We Must take it seriously"

Nick van der Leek speaks to Scientific Director of Retroscreen Virology, Professor John Oxford

I'm underground. Actually I'm in an underground art gallery attached to Olievenhuis in Bloemfontein. I'm sitting at a table filled with pharmacists and doctors. And Professor John Oxford, an expert on the virology surrounding avian influenza is the guest speaker.

We're actually here to launch Tamiflu, so I am surprised that Oxford paints such a rich background. He hardly mentions Tamiflu, and the young woman beside me (a pharmacist) confirms that at these launches (and they attended a smiliar one last week) the experts try not to bore their audience.

Oxford talks about a pre-emptive strike. And Tamiflu is part of how we combat bird flu. If there is an outbreak, and less than 50 people in a given area are infected, and one has a deluge of Tamiflu, you can break the back of this pandemic.

The counterargument for all this preparation is: If there are only 100 people dead, what are we all so worried about.

Well, I ask Professor Oxford where we are, compared to 1918, in terms of the evolution of the virus, which killed upwards of 40 million over an 18 month period (250 000 in South Africa). He placed us at about 1915. I was very suprised to get a specific answer out of him, as I have interviewed and exposed myself to other experts who are less certain. In that snippet is the implicit prediction: 3 years.

I watched the topic of bird flu discussed on Oprah, and Oxford also alludes to both the Tsunami (his 17 year old daughter was wandering around on a beach in Sri Lanka at the time)and New Orleans and recent examples of tragedies that could have been avoided by early warning systems. There is some infrastructure in place, but not enough. "We must take it seriously," he says. After all, a pandemic will trump all the major disasters we have seen in the past, put together: war, famine, Aids, etc.

The question does emerge then: how can a little virus that has 8 genes pull us - people who have 100 000 genes - into bed and kill us? The experts who came up with Tamiflu have found a way to prevent the virus from budding - a vital stage where the virus gets stuck to the surface of cells, so that the drug aborts the infection, and the immunse system then kicks into action.

Tamiflu is being launched in Bloemfontein. That should give you some idea of how much intensity is going on behind the scenes. I ask Professor Oxford if he is aware of the reports of human to human transmissions in Indonesia (reported in the last day or so). He tells me he received a call today with that information.

He also says: "For the history of humankind we have been powerless (against this sort of thing), but now we are not."

Newsbytes:
WHO confirms 31st death in Indonesia and the sixth death in Egypt. The global death toll stands at 123.

Experts looking for bird flu spread watch for deaths
Wed May 24, 2006 3:26 PM ET
(Page 1 of 2)
By Maggie Fox, Health and Science Correspondent

WASHINGTON, May 24 (Reuters) - A suspicious-looking cluster of human bird flu cases in Indonesia illustrates just how difficult it will be to detect the beginning of a pandemic, should one occur, scientists said on Wednesday.

The World Health Organization issued assurances on Tusday that the virus had not changed into a clearly dangerous form, but experts said if it had changed, the information would have come much too late.

In fact, they said, the only way anyone will know that a dangerous form of the virus is circulating will be when people start to become sick and die in large numbers.

"We are not going to know it until a lot of people are infected," said Dr. Eric Toner, an expert in emergency medicine at the Center for Biosecurity at the University of Pittsburgh Medical Center.

And the canaries in the mine will be people trying to cope with the outbreak.

"If it being transmitted efficiently, we would see health care workers being sick," Toner said.

High technology genetic sequencing may give some answers after the fact, but the only way to actually detect a beginning epidemic will be after it has already started, using old-fashioned epidemiology -- the study of a disease's impact on a population.

"We have to, because the genetics of the virus is going to come too late," said Dr. Arnold Monto, an expert in infectious disease epidemiology at the University of Michigan. It takes days or weeks to completely sequence the eight genes of a flu virus.

WHO hopes that countries will be able to quickly identify and isolate human cases of bird flu while investigators check to see how dangerous the strain is.

But the case in Indonesia shows this does not often happen in the real world.

"We are going to be making some crucial decisions based on very incomplete information and speed is of the essence here," said Michael Osterholm, an infectious diseases expert at the University of Minnesota.

And nothing happened speedily in Indonesia. "The first cases were in late April," Osterholm said. WHO issued its first definitive statement on the situation on Tuesday -- nearly a month later.

Had efficient and sustained human transmission been underway, that would be time for many people to have been infected.

The H5N1 avian influenza virus is still almost exclusively a bird virus. It has killed or forced the culling of hundreds of million of birds as it has moved through Asia, across Europe and into many parts of Africa.

It only occasionally infects people -- 218 in 10 countries, killing 124 of them. But only a few genetic changes would allow the virus to easily infect people, and it would likely sweep around the world if this happened, killing millions.

Scientists fully expect the occasional human case of avian flu. But they become more concerned when they see a cluster, like the case of the seven family members in the northern part of Indonesia's Sumatra island.

So far everyone known to have been infected was either in close contact with an infected bird, or in very close contact with an infected person -- and in fact, with a blood relative, which suggests some people may be genetically susceptible to infection.

But in Indonesia it is not yet clear how the first victim in this cluster, a 37-year-old woman, became infected.

Scientists were reassured by the first genetic analysis of virus samples taken from some of the Indonesian patients, although no one is certain of all the genetic changes that would be needed to allow the virus to infect many people.

"We do know some of the things to look for -- we know some of the virulence elements," Monto said.

"But I think the proof in the pudding is watching what happens in the region."

WHO: No urgent meeting on bird flu

Wednesday, May 24, 2006; Posted: 9:50 a.m. EDT (13:50 GMT)
story.bird.flu.indonesia.ap.gif
The only remaining member of a family killed by bird flu is treated in Indonesia's Northern Sumatra province.
World Health Organization (WHO)
Bird flu

JAKARTA, Indonesia (Reuters) -- Limited human-to-human transmission of bird flu might have occurred in an Indonesian family and health experts are tracing anyone who might have had contact with them, the World Health Organisation said.

But a senior WHO official said in Jakarta this was not the first time the world was seeing a family cluster and said that fresh scientific evidence has shown the virus in Indonesia has not mutated to one that can spread easily among people.

WHO said on Wednesday it had no immediate plans to call a meeting of experts to discuss raising its global bird flu alert.

"Right now it does not look like the task force will need to meet immediately, but this is subject to change depending on what comes out of Indonesia," WHO spokeswoman Maria Cheng said, when asked to comment on press reports of an imminent meeting.

Financial markets, however, were spooked on fears the Indonesia cluster could be the start of a pandemic. Currencies in Asia, where most bird flu cases have occurred, fell. U.S. commodity prices came under pressure while European markets slipped as investors turned jittery.

Concern has been growing about the case in north Sumatra in which seven family members from Kubu Sembilang village died this month. The case is the largest family cluster known to date.

WHO and Indonesian health officials are baffled over the source of the infection but genetic sequencing has shown the H5N1 bird flu virus has not mutated, the U.N. agency said on its Web site (http://www.who.int) on Tuesday.

Nor was there sign of the virus spread among villagers.

"To date, the investigation has found no evidence of spread within the general community and no evidence that efficient human-to-human transmission has occurred," the WHO said.

Sick poultry have been the source of bird flu infection for most human cases worldwide. Pigs are susceptible to the virus.

Clusters are looked on with far more suspicion than isolated infections because they raise the possibility the virus might have mutated to transmit efficiently among humans.

That could spark a pandemic, killing millions of people.

The WHO statement came after one of the family members, a 32-year-old father, died on Monday after caring for his ailing son, who had died earlier. The agency said such close contact was considered a possible source of infection.

Closing in

But Firdosi Mehta, acting representative of the WHO in Indonesia, urged against any over-reaction, saying this was not the first cluster that the world has known.

Limited transmissions between people are caused by close and prolonged contact when the sick person is coughing and probably infectious. Experts in Kubu Sembilang were acting to contain any further spread.

"We are going wide, contacting the various contacts, putting on (anti-viral) Tamiflu whoever has had close contact, basically putting family members who have not been affected on Tamiflu as a precaution," Mehta told Reuters in an interview in Jakarta.

"There is active surveillance in the village, fever surveillance to look for any more cases that are occurring outside this immediate family cluster," he said.

But another WHO spokesman said the agency was worried.

"This is the most significant development so far in terms of public health," Peter Cordingley, spokesman for the West Pacific region of the WHO, said in the Philippine capital on Wednesday.

"We have never had a cluster as large as this. We have not had in the past what we have here, which is no explanation as to how these people became infected."

"We can't find sick animals in this community and that worries us," he added.

Bird flu has killed 124 people in 10 nations since it re-emerged in Asia in 2003. It is essentially a disease in birds and has spread to dozens of countries in wild birds and poultry.

In China, where the virus has been entrenched for the last 10 years, fresh trouble may be brewing as authorities confirmed an outbreak of the H5N1 among wild birds in its remote far-western Qinghai province and Tibet.

About 400 wild birds had been found dead "recently", its state Xinhua news agency said, quoting the Agriculture Ministry.

An outbreak of the H5N1 killed thousands of birds in Qinghai Lake this time last year and this strain of the virus has since turned up in parts of Europe, Africa and the Middle East.

Markets are also nervous about a suspected cluster in Iran.

An Iranian medical official told Reuters on Monday that a 41-year-old man and his 26-year-old sister from the northwestern city of Kermanshah had tested positive for bird flu.

But Health Minister Kamran Lankarani denied this although international health officials are still investigating.

The two siblings were among five members of a family who became sick and the other three remain in hospital.

Copyright 2006 Reuters. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed.

No comments: