Timeline of major events H5N1 avian influenza (Part 1)

Early Events

1. 1996 : Events in Animals : Highly pathogenic H5N1 virus is isolated from a farmed goose in Guangdong Province, China.

2. 1997 : Events in Animals : Outbreaks of highly pathogenic H5N1 are reported in poultry at farms and live animal markets in Hong Kong.

3. 1997 : Events in Humans : Human infections with avian influenza H5N1 are reported in Hong Kong. Altogether, 18 cases (6 fatal) are reported in the first known instance of human infection with this virus.

4. Feb 2003 : Events in Humans : Two human cases of avian influenza H5N1 infection (one fatal) are confirmed in a Hong Kong family with a recent travel history to Fujian Province, China. A third family member died of severe respiratory disease while in mainland China, but no samples were taken.


Subsequent Events
1. 25 Nov 2003 : Events in Humans : A fatal human case of avian influenza H5N1 infection occurs in China in a 24-year-old man from Beijing and is attributed to SARS. This case is retrospectively confirmed in August of 2006 (as the 20th human case in China).

2. 12 Dec 2003 : Events in Animals : Republic of Korea first reports H5N1 in poultry. Outbreaks continue through September 2004.

3. Dec 2003 - Jan 2004 : Events in Animals : Viet Nam first reports H5N1 in poultry. Outbreaks continue to be reported on a regular basis. investigation identifies a H5N1 virus similar to that circulating in poultry. This is the first report of influenza causing disease and death in big cats.

4. 8 Jan 2004 : Events in Animals : Viet Nam first reports H5N1 in poultry. Outbreaks continue to be reported on a regular basis.

5. 11 Jan 2004 : Events in Humans : Viet Nam identifies H5N1 as the cause of human cases of severe respiratory disease with high fatality. Sporadic human cases are reported through mid-March.

6. 12 Jan 2004 : Events in Animals : Japan first reports H5N1 in poultry, outbreaks continue in commercial poultry through March 2004.

7. 19 Jan 2004 : Events in Animals : Hong Kong reports H5N1 in a dead wild bird (first report in birds since poultry outbreak in 1997)

8. 23 Jan 2004 : Events in Animals : Thailand first reports H5N1 in poultry. By the end of January, 32 provinces (throughout the north and several in the south) report outbreaks in many types of poultry, including fighting cocks, and outbreaks continue to be reported throughout the year. The virus appears closely related to the isolates from human cases in Viet Nam. Thailand prohibits vaccination of poultry.

9. 23 Jan 2004 : Events in Humans : Thailand reports two laboratory-confirmed cases of human infection with H5N1. Sporadic human cases are reported through mid-March.

10. 24 Jan 2004 : Events in Animals : Cambodia first reports H5N1 in poultry.

11. 27 Jan 2004 : Events in Animals : Lao PDR first reports H5N1 in poultry.

12. 1 Feb 2004 : Events in Humans : Investigation of a family cluster of H5N1
cases, which occurred in Viet Nam in early January, cannot rule out the possibility of limited human-to-human transmission.

13. 2 Feb 2004 : Events in Animals : Indonesia first reports H5N1 in poultry in 11 provinces. Outbreaks continue to be reported. Vaccination is allowed.

14. 4 Feb 2004 : Events in Animals : China first reports H5N1 in poultry. During February-March, 16 mainland provinces are affected, and approx. 9 million poultry culled. Government-subsidized vaccination initiated.

15. 20 Feb 2004 : Events in Animals : A report from Thailand confirms that a domestic cat was infected with H5N1 after eating an infected pigeon.1

16. 18 Mar 2004 : Events in Humans : Research2 Case studies of 10 patients in Viet Nam point to close contact with infected poultry as the probable source of infection in most cases, but conclude that, in two family clusters, limited human-to-human transmission within the family cannot be ruled out.

17. Jun/Jul 2004 : Events in Animals : China reports recurrence of H5N1 in poultry. Outbreaks continue to be reported in Indonesia, Viet Nam and Thailand.

18. 8 Jul 2004 : Events in Animals : Research3 Research identifies the dominant Z genotype in poultry, considers possible role of wild birds in spread, and concludes that H5N1 has found a new ecological niche in poultry, but is not yet fully adapted to this host.

19. 13 Jul 2004 : Events in Animals : Research4 Research shows that H5N1 has become progressively more lethal for mammals and can kill wild waterfowl, long considered a disease-free natural reservoir.

20. Jul 2004 : Events in Humans : Research5 A case report is published indicating atypical human H5N1 infection in Thailand (from March 2004), with fever and diarrhoea but no respiratory symptoms. The report suggests that the clinical spectrum of disease may be broader than previously thought.

21. 12 Aug 2004 : Events in Humans : Viet Nam reports 3 new human cases, all fatal (first cases since February). Dates of hospital admission are from 19 July to 8 August.

22. 19 Aug 2004 : Events in Animals : Malaysia (peninsular) first reports H5N1 in poultry. Outbreaks and positive avian surveillance samples continue to be reported through September 2004.

23. 20 Aug 2004 : Events in Animals : Research6 Chinese researchers report preliminary findings of H5N1 infection in pigs. No evidence suggests that pig infections are widespread, and the finding appears to have limited epidemiological significance.

24. 2 Sep 2004 : Events in Animals : Research7 Research shows that domestic cats experimentally infected with H5N1 develop severe disease and can spread infection to other cats. Prior to this research, domestic cats were considered resistant to disease from all influenza A viruses.

25. 7 Sep 2004 : Events in Humans : A 4th fatal human case is reported in Viet Nam.

26. 9 Sep 2004 : Events in Humans : Thailand confirms its third fatal case of human infection.

27. 28 Sep 2004 : Events in Humans : Thailand confirms 2 further human cases.

28. 4 Oct 2004 : Events in Humans : Thailand confirms its 4th human case.

29. 18 Oct 2004 : Events in Animals : Two healthy Hawk-Eagles smuggled from Thailand are seized at Brussels International Airport. HPAI H5N1 is isolated.

30. 20 Oct 2004 : Events in Animals : A second outbreak of HPAI H5N1 in zoo tigers in Thailand occurs. It is attributed to tigers having been fed fresh chicken carcasses and whole chickens. Altogether, 147 tigers out of a population of 441 die or are euthanized. No virus is detected in birds in zoo or local area.

31. 25 Oct 2004 : Events in Humans : Thailand confirms its 5th human case.

32. 29 Oct 2004 : Events in Animals : Research8 Research confirms that domestic ducks can act as silent reservoirs, excreting large quantities of highly pathogenic virus yet showing few if any signs of illness.

33. 3 Nov 2004 : Events in Animals : Hong Kong SAR reports H5N1 in a dead wild bird (last report January 2004).

34. Dec 2004 : Events in Animals : Poultry outbreaks continue in Indonesia, Thailand, and Viet Nam and possibly also in Cambodia and Lao PDR. Reported outbreaks continue more or less continuously in Indonesia through August 2006, in Thailand through November 2005, and in Viet Nam though December 2005.

35. 30 Dec 2004 : Events in Humans : Viet Nam confirms a new case.