Avian Flu - What we need to know

Vietnam update

In an impressive burst of action, Vietnam, once the epicenter for bird flu, has temporarily stamped out the disease: no people infected since November, and no poultry outbreaks since December.

The poor communist nation says it accomplished this feat by vaccinating millions of chickens and ducks, slaughtering millions more, by being honest with international health officials, and by educating its citizens.

There were even crackdowns on local delicacies, like duck blood pudding, believed to be the source of at least one death.

[...] Vietnam spent $18.9 million vaccinating 120 million birds last year and plans to immunize 160 million more birds, said Hoang Van Nam, deputy director of the Department of Animal Health. Eighty percent of the poultry sampled after vaccination had enough immunity to protect against the disease and none was found to be carrying the virus.

China claims to have vaccinated all of its 14 billion domestic birds, but it has continued to see outbreaks and human infections. Last week, Shanghai logged its first human bird flu death, bringing the human toll in China to at least 11, according to WHO.

Widespread immunization requires thousands of workers who must keep the vaccine chilled and return to farms to give booster shots three or four weeks after the first inoculation. A third injection is given four months later to poultry raised up to a year. But many birds have much shorter life spans, meaning the cycle constantly starts over.

Read more at CNN.

Avian flu vaccine safe but not very effective

The vaccine, which the United States already is stockpiling in the event of a pandemic, was given to 451 healthy adults between the ages 18 and 64, making it the largest such study to date.

[...] Of the participants given two shots of the highest dose of the vaccine 28 days apart, only 54 percent of them had adequate protection from the virus when researchers tested their blood for antibody response. Not all participants were given the same dosage.

Researchers were trying to determine if the vaccine is safe and what dosage would provide sufficient protection from the virus should it become pandemic. The ongoing clinical trials are being funded by the National Institutes of Health.

[...] the study, published in the March 30 edition of the New England Journal of Medicine, shows that while the shot is safe, only about half of those receiving the highest dose of the vaccine -- 90 micrograms -- produced enough antibodies to stave off H5N1 bird flu, if they were exposed.

The seasonal flu shot, by comparison, provides adequate protection in 70 to 90 percent of those receiving one 15-microgram dose of the vaccine.

Source, here is the NEJM paper (available for free). Effect Measure has more.

US to stockpile Relenza

The U.S. health department said it ordered about 1.75 million courses of Relenza on March 2 and another 2.2 million courses on March 26.

The department has already ordered 22 million courses of Tamiflu, which until the launch of Relenza was the only drug on the market with the capabilities to prevent influenza A and B and also be used as a treatment for people with the infection.

From CNN.

Avian flu stock index

Trend Macroanalytics, a research firm serving institutional investors, has taken its analysis a step further and created an "avian-flu index" comprising 17 stocks in the health-care sector that can be expected to see a surge in demand for their products should the flu become a threat to humans.

[...] Donald Luskin, chief investment officer at Trend Macro, said the index has gained 105% since its inception last Aug. 31 and is up 40.5% so far in 2006.

Source.

New York Times articles

Two contrasting pieces in the NYT yesterday, one by Elisabeth Rosenthal - The Skeptic, and another by Donald McNeil - The Worrier. If you like the worrier/skeptic debates you may also enjoy Revere's Effect Measure post taking on an article by Marc Siegel.

Using horse antibodies to fight bird flu

Chinese scientists have produced antibodies in horses that are an effective treatment for bird flu – at least in mice.

Jiahai Lu at Sun Yat-sen University in Guangzhou and colleagues repeatedly inoculated horses with a chicken vaccine against H5N1 bird flu to make them produce antibodies.

They then collected the horses’ blood, separated out the antibodies and split them to make them less likely to cause an allergic reaction when injected into a human. When they injected mice with a tenth of a milligram of these antibodies 24 hours after they had been given an otherwise lethal dose of H5N1, all the mice lived.

In theory, such antibodies could be made quickly against a pandemic strain of H5N1, potentially saving many lives and limiting the spread of the virus. The trouble is that most drug companies have stopped making antibodies this way.

This is because keeping horses is expensive and until now the markets for antiserum have been in poor countries and offer low financial returns. In addition, animal rights campaigners object to the technique.

Companies have instead invested in making modern, monoclonal antibodies using cell cultures. "It would be complex and expensive for a company to hugely scale up its monoclonal production to treat whole populations rather than a few people,” says David Fedson, founder of the vaccine industry’s pandemic task force.

Source.

New casualty in Egypt

A 30-year-old woman died of the H5N1 bird flu strain on Monday, Egypt's second human death from the virus since it appeared in the country last month, the health ministry announced. Czech authorities said they suspected their first case of H5N1 in a dead swan.

Fatma Mahmoud Youssef Sabra came from a village just north of Cairo, near Egypt's other human bird flu death, said Abdel-Rahman Shahin of the health ministry.

Source.

US government's flu website

If you haven't done so in a while it may be worth browsing through pandemicflu.gov, the government's flu website. Lots of information and preparedness advice.

The difficulty of containing bird flu

The speed of its migration, and the vast area it has infected, has forced scientists to concede there is little that can be done to stop its spread across the globe.

"We expected it to move, but not any of us thought it would move quite like this," said Dr. David Nabarro, the United Nations' coordinator on bird flu efforts.

The hope was once that culling millions of chickens and ducks would contain or even eradicate the virus. Now, the strategy has shifted toward managing a disease that will probably be everywhere. Officials are hoping to buy a little more time to produce human vaccines and limit the potential economic damage.

"We cannot contain this thing anymore. Nature is in control," said Robert G. Webster, a virologist at St. Jude Children's Research Hospital in Memphis, Tenn., who has been studying the virus since it emerged in 1997.

Read the full article here, and some commentary at Effect Measure.

Six new suspected cases in Asia

Three people were under observation in Cambodia today, suspected of having contacted bird flu:

The three -- one adult and two children -- are being treated for fever and respiratory problems at a hospital in the capital Phnom Penh, said Ly Sovann, head of the health ministry's department of infectious diseases.

The suspected cases come from a village neighbouring that of a three-year-old girl who died Tuesday after falling ill with the H5N1 strain of the virus.

Five other people who had contact with the suspected cases are also being tested, Ly Sovann said.

It is unknown how the three might have become infected with the deadly virus, Ly Sovann said.

Seven Cambodians thought to have caught bird flu after the girl died tested negative for the virus, Ly Sovann said earlier.

"All the seven suspected patients are negative ... all of them are better," he said.

AFP also reports two new suspected cases in Malysia:

A three-year old girl from northern Penang state and a 26-year-old man from neighbouring Perak state are in isolation while awaiting test results for the H5N1 virus, said the ministry's director for disease control, Ramlee Rahmat.

"They have been isolated pending further investigation. They are both stable," Ramlee told AFP. "The test results will come back in one or two days."

Finally, Indonesia reported today a one year old girl who died eariler this week tested positive for bird flu:

The girl, a resident of West Jakarta, died Thursday at Jakarta's Sulianti Saroso main state-run hospital for bird flu patients, said health ministry official Hariyadi Wibisono.

"The local tests for the girl came out positive. She had a history of contact with sick chickens near her house and suffered serious respiratory problems during hospitalisation," Wibisono told AFP.

Samples from the girl have been sent to a Hong Kong laboratory accredited by the World Health Organisation for confirmation, the official said.

If confirmed, the girl would be Indonesia's 23rd bird flu fatality. Results from local tests are usually accurate.