Timeline of bird flu spread

1890 First recorded recent influenza pandemic

1918 The Spanish Flu pandemic, caused by the H1N1 influenza virus, kills more than 40 million people. The origin of H1N1 remains a mystery, but may have involved incubation in an intermediate host, such as the pig, or another as yet unidentified animal host.

1957 Asian flu pandemic kills 100,000 people, due to the H2N2 influenza virus.

Hong Kong flu pandemic kills 700,000 people, due to the H3N2 virus. Both H2N2 (1957 pandemic) and H3N2 are likely to have arisen by exchange of genes between avian and human flu viruses, probably following dual infection in humans.

May 1997 Bird flu virus H5N1 is isolated for the first time from a human patient in Hong Kong. The virus infects 18 patients after close contact with poultry, with six deaths. Fortunately the virus does not spread from person to person. Within three days, Hong Kong's entire chicken population is slaughtered to prevent further outbreak.

Sept 1998 Trial results announced for two new influenza drugs that target the viruses neuraminidase enzyme, Relenza and Tamiflu.

1999 Two new flu drugs, Relenza and Tamiflu, are licensed in US and Europe.

2001 The World Health Organization (WHO) outlines its new global laboratory proposal, aimed at improving the range, speed and quality of influenza virus surveillance.

Feb 2003 Alarm bells are again raised when the avian virus H5N1 infects two people in Hong Kong, one died.

Feb 2003 Outbreaks of chicken flu occur in The Netherlands due to the H7N7 avian flu virus. By April the virus has spread to nearly 800 poultry farms and resulted in the culling of almost 11 million chickens. The virus infects 83 people causing conjunctivitis and flu-like symptoms, and kills one man. The drug Tamiflu helps protect people against further spread of the virus.

Dec 2003 South Korea has its first outbreak of avian flu in chickens, caused by H5N1.

Jan 2004 Japan has the first outbreak of avian influenza (H5N1) since 1925.

Jan 2004 WHO confirms H5N1 infection in 11 people, eight fatal, in Thailand and Vietnam, but no cases of person to person transmission. The virus has wreaked havoc among poultry in Thailand, Vietnam, Japan and South Korea, and has also appeared in a duck farm in China. WHO is developing vaccine candidates using H5N1 viruses isolated in 2003 and 2004, at laboratories in the U.S. and U.K.

Feb 2004 United Nations Food and Agriculture Organization advises governments in affected areas that mass culling of birds is failing to halt the disease and that vaccination of targeted poultry flocks is required as well.

March 2004 Avian H5N1 flu virus becomes more widespread among bird flocks in Asia, and has caused 34 human cases, with 23 deaths.

6 April 2004 Avian influenza virus H7N3 confirmed in two poultry workers in British Columbia who developed flu-like symptoms.

June 2004 Tests on chickens and mice show that avian flu H5N1 virus isolated from ducks in 2004 is more virulent and harmful to mammals than in recent years.

July 2004 Several countries, including Thailand, Vietnam, China and Indonesia, report new infections in poultry with H5N1.

Aug 2004 H5N1 is reported to have killed an additional three people in Vietnam.

Chinese scientists report H5N1 avian flu infection in pigs, raising concerns that the virus could exchange genes with human flu strains in this 'mixing vessel'.

H5N1 virus has spread throughout most of SE Asia, resulting in the culling of over 100 million chickens. In Vietnam and Thailand, the virus has infected at least 37 people, with 26 deaths.

Oct 2004 UK authorities suspend manufacturing of this years routine influenza vaccine at the Liverpool factory of Chiron, owing to sterility concerns. The move leads to vaccine shortage particularly in the U.S. where Chiron supplies 50 per cent of the market, and highlights the need for alternative manufacturing sources.

Nov 2004 WHO warns that the H5N1 bird flu virus might spark a flu pandemic that could kill millions of people, and is concerned that "much of the world is unprepared for a pandemic" and needs to enhance preparedness to reduce its potential impact.

WHO officials meet with vaccine makers, public-health experts and government representatives in a bid to speed up the production of flu vaccines to avert a global pandemic.

Dec 2004 WHO reports the first human case of H5N1 in Vietnam since early September.

Sequencing of the chicken-genome (published in Nature 9 December 2004) may help provide insight into which genes prevent the spread of bird flu from person to person.

Since the beginning of 2004, bird flu has caused the deaths of 32 people in Vietnam and Thailand, and millions of chickens across Asia.

Jan 2005 Chinese authorities announce they have developed a new rapid test for bird flu that produces results in hours rather than days.

Jan/Feb 2005 13 additional cases of bird flu have occurred in Vietnam since December 2004, 12 fatal.

Feb 2005 First report of a bird flu case from Cambodia.

A report of probable person to person transmission of bird flu in Vietnam is published (New Engl. J. Med, 333 340)

WHO has made prototype H5N1 vaccine strains available to a number of institutions and companies and several vaccines have been developed for clinical testing.

March 2005 15 additional cases of H5N1 infection in Vietnam, and one additional case in Cambodia, are reported.

Bird flu has spread to 10 countries, including Democratic People's Republic of Korea, and killed around 50 million chickens.

April 2005 Vietnam has reported a total of 60 laboratory confirmed human cases of H5N1 avian influenza since the outbreaks began, with 35 deaths; Thailand has confirmed a total of 17 infections of which 12 have been fatal, while Cambodia has confirmed two fatal cases.

May 2005 Rumors of human deaths in China from H5N1 remain unconfirmed, while the virus has killed more than 1000 migratory birds. Indonesia's government confirms reports of H5N1 infection in pigs.

19 May 2005 WHO reports 97 cases and 53 deaths from bird flu in Vietnam, Cambodia and Thailand since January 2004.

June 2005 Indonesia confirms a man exposed to sick chickens has been infected with a deadly strain of avian flu virus. The farm laborer shows no symptoms, but his blood carries antibodies to the H5N1 strain.

Bird flu becomes resistant to the low-cost Amantadine family of antiviral drugs. Chinese farmers' use of the compound in chickens is blamed, a claim formally denied by Chinese authorities who pledge to investigate the claim.

July 2005 At the end of a three-day conference in Malaysia, World Health Organization officials announce that $150 million is needed to fight the spread of the disease in people and another $100 million to stop its spread in animals in Asia.

The Philippines, so far the only Asian country unaffected by bird flu, report their first case in a town north of the capital, Manila, but do not confirm whether it is the H5N1 strain.

July 20 Indonesia confirms its first deaths from bird flu.

July 26 Japan says a fresh outbreak of bird flu has been discovered on a chicken farm in east Japan. All outbreaks in the Ibaraki prefecture were confirmed as the weak H5N2 strain.

Aug 10 Bird flu virus has been found in Tibet, the world animal health body OIE says.

Aug 15 Russia reports an outbreak of bird flu in the Urals region of Chelyabinsk.

Aug 23 Outbreak of the H5N1 bird flu strain in seven villages in Kazakhstan is confirmed as dangerous to humans.

Sept 1 Vietnam reports one new human death from bird flu, taking its total to 44. 65 people have died in Asia in total, including 12 in Thailand, five in Indonesia, four in Cambodia.

Oct 8 Turkey reports cases of avian flu, and Romania reports suspected avian flu. Both kill birds to prevent the disease from spreading.

Oct 10 Bosnia, Croatia, Bulgaria, Switzerland announce a ban on poultry imports from Turkey and Romania. The European Commission bans imports of live birds and feathers from Turkey to the 25-nation EU.

Oct 15 British tests identify H5N1 in three ducks found dead in Ceamurlia de Jos in Romania, the first incidence in mainland Europe of H5N1. Oct 17 Greece says H5 bird flu -- which can range from a mild form to H5N1 -- has been detected on the Aegean island Chios, the first such case in an EU member state. Oct 21 Hungary says a vaccine against the deadly strain of bird flu has proven effective. Scientists also detect the H5 avian flu virus in wild swans found dead in eastern Croatia. Oct 23 Britain says that a parrot that died in quarantine in Britain has been found to have the deadly H5N1 strain. Oct 25 Indonesia reports the death of a man from bird flu which, according to the World Health Organization, brings the human death toll throughout Asia to 62, comprising 41 in Vietnam, 13 in Thailand, four in Indonesia and four in Cambodia. Oct 29 Director of hospital in Vietnam says two people showing symptoms of the bird flu virus have die. A third person is being treated in a hospital.