(Update) Avian Flu at Final Phase ?

Commentary
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H5N1 2005 Pandemic at Phase 5 or 6?

Recombinomics Commentary
May 22, 2005



The commentary (by WHO) on lack of human-to-human transmission simply misrepresents the available data. The association with poultry, especially in 2005, is similar to observations that virtually all index cases in clusters woke up on a Tuesday and developed bird flu symptoms within 7 days.

Most of the associations between index cases of clusters with poultry have been extremely weak. Blood pudding meals, meals at neighbors, proximity to slaughter houses etc, provide little evidence for a causal relationship. Others who ate the same meal had no symptoms or evidence of exposure, and the index cases generally developed symptoms too soon or too late after the suspect meal.

The evidence for human-to-human transmission was overwhelming in 2004. Common exposures generally produce symptoms at the same time, while human-to-human transmission produce a bimodal distribution of disease onset dates. The familial clusters at the beginning of 2004 were bimodal, strongly suggesting human-to-human transmission in all or most clusters. Last summer larger clusters in Vietnam and Thailand left little doubt that the familial clusters were generated by localized human to human transmission, which placed the pandemic at phase 4.

In 2005 the size of the bird flu clusters grew larger and the clusters began to cluster, moving the 2005 pandemic to phase 5, which is define by larger localized clusters. The real question at this time is whether level has moved to 6, due to widespread community transmission that is not recognized by because of lack of testing or reporting.

The genetic changes currently being reported in northern Vietnam are due to additional recombination. These changes are far from random and accumulate in the population due to selection advantages.

H5N1 has been evolving via changes in genes due to recombination. There has been no reassortment with human genes and little reason to expect such recombination. Human pandemics last century were driven by a change in the hemagglutinin gene. 1918 was caused by H1. 1957 was caused by H2. 1968 was caused by H3. There is no reason to expect the pandemic of 2005 to be caused by a reassorted H1 or H3. H5 is being modified to cause the 2005 pandemic. No reassortment required.

WHO has stopped proclaiming the absence of human genes in H5N1 isolates. The "novel human pathogen" is H5, with an expanded host range, not H5 swapped back to H1 or H3. Such a mechanism has never made any sense, and it is unfortunate that the editor of a widely read newsletter like ProMed would continue to post such comments at this stage of H5N1 evolution.

Human-to-human transmission of H5N1 is well established. The only real question is whether the current pandemic is at phase 5 or the final phase 6.

http://www.recombinomics.com/whats_new.html

Thanks, please keep us posted.

All hands on deck as bird flu reappears in China
By Hamish McDonald Herald Correspondent in Beijing
May 24, 2005

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The Chinese Health Minister yesterday cut short a visit to Japan as China's health and agriculture agencies began emergency measures to stop an outbreak of a deadly avian influenza strain spreading from wild birds.

The Vice-Premier, Wu Yi, who also holds the health portfolio, cancelled a meeting with the Japanese Prime Minister, Junichiro Koizumi, citing urgent duties back in China.

Although some reports said this might have been a snub related to Mr Koizumi's visits to the controversial Yasukuni shrine honouring Japan's war dead, Japanese officials told reporters they had been specifically assured by the Chinese this was not the case.

Ms Wu, the highest-ranked woman in the Chinese Government and a career trade negotiator, was put in charge of the health ministry after her predecessor was sacked for helping to cover up the spread of severe acute pneumonia syndrome, or SARS, two years ago.

But as Ms Wu returned to supervise the latest battle against a dangerous virus, China still seemed caught between openness and secrecy.

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AdvertisementAgriculture and health officials announced at the weekend that the deadly H5N1 avian flu virus had been found in 178 migratory geese found dead in a remote lake on the Tibetan plateau in early May.

But yesterday Hong Kong newspapers said thousands of dairy cattle were being slaughtered on the outskirts of Beijing because of an outbreak of foot-and-mouth disease that government agencies were covering up. The avian flu cases are the first discovered in China since outbreaks were brought under control last year through the mass culling of infected flocks and vaccination of domestic fowl.

But the disease has kept hold in South-East Asia, with Vietnam yesterday reporting the death of a 46-year-old man from Khoai Chau district, bringing the death toll in Vietnam to 38 from 78 human infections detected since December 2003. A further 12 people have died in Thailand from the same virus and four in Cambodia.

The World Health Organisation is warning that a mutation might be near that allows the virus to jump from human to human, creating a deadly epidemic that could kill millions before vaccines are brought into mass production.

Chinese authorities yesterday rushed 3 million doses of vaccine against the H5N1 strain to protect domestic bird flocks in Qinghai province, where the dead bar-headed geese were found.

The birds are among many migratory species that come in the northern spring to breed in the lakes and marshes of Qinghai, a high-altitude plateau sparsely populated by ethnic Tibetans. The bar-headed geese winter in India and fly across the Himalayas at altitudes as high as 9400 metres to breeding grounds in Central Asia.


http://www.smh.com.au/news/World/Al...a/2005/05/23/1116700652544.html?oneclick=true

Chinese authorities yesterday rushed 3 million doses of vaccine against the H5N1 strain to protect domestic bird flocks in Qinghai province, where the dead bar-headed geese were found.

Click to expand...

Anybody know where they got the vaccine?


tsk, tsk...

Monday, May. 23, 2005
Bird Flu Picks a Genetic Lock

Asia's H5N1 virus may be getting less virulent—but more dangerous
BY BRYAN WALSH

The most frightening aspect of avian flu has always been its astonishing virulence, but the human death rate in hard-hit northern Vietnam has fallen to 34% this year, down from almost 80% for the entire country in 2004. Good news? Not if you're an epidemiologist. Investigators for the World Health Organization (WHO) have raised concerns that even though the H5N1 bird-flu virus appears to be weakening, it may be adapting better to human beings—potentially opening the door to a flu pandemic.

Researchers have found that as the fatality rate dropped in northern Vietnam, there has been an increase in the number of cases clustered close together and in the age of those infected—signs that the virus may be finding more efficient ways to infect people, including human-to-human transmission, the principal barrier to a pandemic. The falling death rate could mean that this process of adaptation is accelerating. "In gaining the ability to go from one person to another, a virus may well lose its virulence," says Dr. Jeremy Farrar, director of the Oxford University Clinical Research Unit at the Hospital for Tropical Diseases in Ho Chi Minh City. The 1918 Spanish flu, for example, the worst pandemic in history, had a fatality rate of 2.5%. But it was extremely contagious, infecting hundreds of millions.

The data from Vietnam is still far from conclusive, and the reduced fatality rate may be due to more experienced investigators detecting the sort of mild cases they might have missed last year. But that wouldn't explain the difference between situations in Vietnam's north and in the south, where the death rate has remained high and infections have remained comparatively low. Either way, public-health experts are preparing for the worst. Says Dr. Peter Brown, a WHO epidemiologist: "If we wait until we definitely know there is a problem, it may be too late."



http://www.time.com/time/asia/magazine/printout/0,13675,501050530-1064512,00.html

Avian flu virus discovered on eggs from Vietnam



Matthew Lee


May 19, 2005



The deadliest form of the avian influenza virus was found in Guangdong for the first time last month on 45 eggs brought in by air from Vietnam by two passengers.

According to the Guangdong Entry-Exit Inspection and Quarantine Bureau report Wednesday, officials at the Guangdong airport discovered the eggs in the hand luggage of the passengers on separate flights from Vietnam on April 28.

Sniffer dogs detected the eggs, of which five were chicken eggs, five duck eggs, five goose eggs and 30 fertilized duck embryos. The eggs were immediately sent to the provincial and state laboratories for tests as they came from a bird-flu-infected area, the report said.

Most of the duck-embryo shells were cracked and the embryos dead.

The duck and goose eggs tested positive for the highly pathogenic H5N1 bird flu virus.

Scientists from the provincial laboratory said in the report the virus is virulent and can kill the embryos quickly. The death rate for poultry is up to 100 percent.

It was the first bird-flu-infected eggs discovered since several Southeast Asian countries were affected by the outbreak last year.

According to the World Health Organization, Vietnam has reported 68 cases of bird flu in humans since May 4 last year, of whom 36 have died since January this year.

Infectious disease expert Lo Wing-lok said the virus can survive on the surface of an egg for days.

"The Vietnam government stepped up bird flu control measures two weeks ago after studies revealed that 70 percent of waterfowl found in the Mekong River Delta area were carrying the virus,'' Lo said. "The measures include a massive cull of all waterfowls and a ban on hatching duck and goose eggs until February 2006.''

He suggested the measures were one possible reason for the export of the embryos from Vietnam.

"Although it is theoretically possible for the bird flu virus to penetrate the eggshell, so far, viruses like these have only been found outside the shell,'' Lo said.

"The risk of human infection from eating the eggs are relatively low because the eggs, unlike live poultry where the virus can multiply, only carry a fixed amount of the virus,'' he said, adding the virus on the eggshell can be washed away.

A Health, Welfare and Food Bureau statement said the Food and Environmental Hygiene Department has liaised with mainland authorities about the contaminated eggs in Guangdong.

"Imports of table eggs do not require prior approval. Samples are, however, taken at entry, wholesale and retail levels for testing. The results are satisfactory so far. Imported hatching eggs must be, however, be disinfected on arrival at local hatcheries,'' it said.

http://www.thestandard.com.hk/stdn/std/Metro/GE19Ak02.html