May 1997 - The first known human cases of the bird flu virus H5N1 are reported in Hong Kong. The virus infects 18 people working in close contact with poultry. Six of them die.
Dec 2003 - South Korea has its first outbreak of the virus at a chicken farm near Seoul and begins a mass cull of poultry as it spreads across the country.
Two tigers and two leopards die in a Thailand zoo after being fed fresh chicken carcasses. Subsequent tests confirm H5N1 virus is present. This is the first documented case of bird flu causing disease and death in big cats.
Jan 2004 - Bird flu is found on poultry farms in Vietnam, Japan, Thailand, Cambodia and Laos. Thailand reports two cases of humans infected with H5N1 by poultry.
Feb 2004 - Indonesia and China report H5N1 in poultry farms.
Jul-Aug 2004 - Vietnam reports three new fatal cases of humans infected by the H5N1 virus. Malaysia reports H5N1 in poultry farms.
Sep 2004 - Thailand confirms a fatal case of human infection.
Feb 2005 - Cambodia reports first human case of H5N1. The case is also fatal.
Jul 2005 - Indonesia reports first human case.
Russia reports cases of H5N1 in poultry and migratory birds in western Siberia.
August 2005 - Kazakhstan reports outbreak of H5N1 in poultry adjacent to Siberia.
China reports poultry outbreak in Tibet region.
Mongolia reports death of 89 migratory birds infected with H5N1.
Roche Pharmaceuticals donates 3m doses of the drug Tamiflu to the WHO to build stockpiles to prevent or contain a possible pandemic.
Sep 2005 - Sanofi-Pasteur, a French Pharmaceutical company, enters into a $100m contract with the US Department for Health and Human Services to produce doses of a vaccine protecting against avian flu.
Oct 2005 - Turkey reports the first case of bird flu in poultry farms, later confirmed as the dangerous H5N1 strain, marking the first case in mainland Europe.
The European Commission announces a ban on imports of live birds and feathers from Turkey to the European Union. Later, British tests identify H5N1 in dead ducks in Romania and Croatia confirms H5N1 in wild birds.
Chiron Pharmaceuticals enters into a $65.5m agreement with the US to supply avian flu vaccine.
Nov 2005 - At a talk in Geneva, health experts agree to a billion-dollar strategy to minimise the virus threat.
Kuwait reports bird flu in a culled flamingo–its first case of H5N1-and China reports its first two cases in humans.
Dec 2005 - Ukraine sends troops to patrol exclusion zones in Crimea where the virus was detected in poultry.
Jan 2006 – Roche Pharmaceuticals donates a further 2m doses of Tamiflu to the WHO.
UK, France, Finland, Iceland, Ireland, Luxembourg, the Netherlands, New Zealand, Norway and Switzerland all order quantities with the intention of stockpiling the drug for 20% – 40% of their populations.
Cyprus confirms lethal H5N1 strain in poultry.
Iraq reports first human case of H5N1.
Turkey reports that two teenagers from the same family have died from bird flu.
Feb 2006 - Austria, Azerbaijan, Bulgaria, Bosnia-Herzegovina, Denmark, Egypt, France, Georgia, Germany, Greece, Hungary, India, Iran, Italy, Niger, Nigeria, Poland, Russia, Slovakia, Slovenia, and Sweden all report the H5N1 strain in birds.
Chinese corporation Skystar Bio-Pharmaceutical announces plans to develop avian flu vaccine by early 2007.
The EU bans imports of untreated feathers and pledges €2m for surveillance programmes of the virus.
The UK enters agreements with pharmaceutical companies Baxter and Chron to build up stockpiles of vaccine.
GlaxoSmithKline announces plans to investigate development of vaccine.
Mar 2006 - Afghanistan, Albania, Cameroon, Czech Republic, Israel, Jordan, Myanmar, Pakistan, Poland, and Switzerland confirm H5N1 in birds.
Azerbaijan reports three fatal human cases of H5N1, and Egypt confirms its first human case of bird flu.
Roche, maker of Tamiflu, announces plans to increase production of the avian flu treatment from 300m to 400m by the year.
Apr 2006 - Burkino Faso confirms H5N1 in poultry, as Germany confirms its first case of H5N1 in domestic fowl.
The UK reports its first case of H5N1 in a dead swan in Scotland.
May 2006 - The Côte d’Ivoire and Sudan confirm H5N1 in poultry.
Russia begins human clinical trials of a bird flu vaccine, and Thailand announces it will conduct its own vaccine trials.
Jun 2006 - The EU offers European farmers up to €65m to cope with bird flu.
Jul 2006 - Spain detects its first case of bird flu in an autopsy of a great crested grebe. Thailand bans poultry imports from neighbouring countries to prevent new outbreaks.
Aug 2006 - Reports suggest that the spread of the virus is slowing worldwide and efforts to contain the illness are partially succeeding
Feb 2007 - Tests in Britain show H5N1 killed 2,500 turkeys on a farm in eastern England. This is the first outbreak in British poultry. Tens of thousands of turkeys are gassed to prevent the spread of deadly bird flu.
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