17 June = 2005

17 June 2005

H5N1 in=20 Thailand: Public Health and Political Response Temporally Linked with = Lack of=20 New Human Cases since October 2004.

Since=20 the first human infections with the H5N1 avian influenza virus in = Thailand 18=20 months ago, in January 2004,=20 Thailand has organized an admirable high-level public health and = political=20 campaign against the virus in poultry and humans. This intense nation-wide = effort to=20 control H5N1, publicly announced in October 2004 by the upper high = levels of the=20 Thai government, has been temporally linked with the absence of any = human cases=20 of H5N1 since October 8, 2004. =20 Webster and Hulse (=93Controlling avian flu at the source.=94 = Nature=20 May 26, 2005;435:415-16) commented that =93the culling of ducks in = Thailand (with=20 farmer compensation) has reduced the flocks of ducks that were positive = for H5N1=20 from almost 40% infected in October 2004 to almost undetectable levels = in March=20 2005. Thus, reducing H5N1 infection in poultry clearly reduces the = threat to=20 humans.=94

On=20 the website of the Thailand Ministry of Public Health (MOPH) Bureau of = General=20 Communicable Diseases, Department of Disease Control, is both a daily = update on=20 human surveillance for avian influenza and an archive of key documents = and=20 information regarding the national response over the past 18 months. For = example, on November 8, 2004 the MOPH published detailed guidance on = =93Avian=20 Influenza: Prevention and Control Measures in Humans=94. Village Health Volunteers were = directed=20 to monitor nationwide for ill or dead birds, and for patients with = flu-like=20 symptoms. Evidence of either ill poultry or humans was to be reported=20 immediately for prompt evaluation. All hospitals and health care = facilities were=20 directed to follow a specific algorithm for standardizing the epidemiologic = exposure=20 history for H5N1, the clinical specimens to be obtained and specific = diagnostic=20 tests to be performed, infection=20 control measures including use of single patient rooms for protective = isolation,=20 x-rays to be performed, and rapid treatment, including use of anti-influenza drug even = prior to=20 final results of H5N1 testing if the patient is ill. =

Medical=20 evaluation and monitoring for fever or flu-like symptoms for family = members and=20 health care workers who had contact with possible H5N1 patients was also = specified in this November 2004 guidance. Surveillance and Rapid = Response Teams=20 (SRRT) were mandated for Provincial Health Offices in both provinces and = districts across Thailand. These teams were to be on-call 7 days a week = to=20 respond to possible H5N1 single cases or outbreaks. Prompt lines of=20 communication were mandated from the level of the SRRT having mobile = phones, to=20 the Provincial Health Office(s), to the Bangkok Metropolis = Administration. Possible outbreaks in poultry = were to be=20 reported immediately to the appropriate corresponding government = organizations=20 related to livestock.

By=20 November 10, 2004 a =93Standard Operating Protocol=94 for evaluating = patients with=20 suspected avian influenza was published, and a clinical management = guideline for=20 such patients in both an outpatient and inpatient setting was revised on = December 2, 2004 by the MOPH Department of Medical Services working = group on=20 medical management. H5N1 patient case definitions were listed on the = Thai MOPH=20 website and the WHO Thailand website =20 for =93suspect=94, =93probable=94, =93confirmed=94, = =93excluded=94 and =93on=20 investigation=94. Between 1 January 2005 and 9 June 2005 the MOPH Bureau = of=20 Epidemiology daily H5N1 surveillance online reporting cited 587 persons = having=20 been evaluated for H5N1 infection, with 583 excluded and four still = being=20 investigated.

On=20 January 25, 2005 the National Cabinet of Thailand approved the = =93National=20 Strategic Plan for Avian Influenza Control=94. Summaries of this plan were = published on=20 websites ranging from the FAO Animal Production and Health Division = Avian=20 Influenza Emergency subsection, to the Tourism Authority of Thailand. = The plan=20 is for the three years from 2005-2007. It contains six strategies and = five=20 specific targets. For example, targets for the control of H5N1 include = no spread=20 of avian influenza in economic poultry within 2 years, and no spread = from=20 animals to humans within 2 years, as well as efficient pandemic = preparedness for=20 influenza within 1 year. = The high=20 level coordination for the =93war=94 on avian influenza in Thailand was = summarized=20 in slides presented May = 18, 2005 at=20 the World Health Assembly in Geneva regarding =93technical briefing on=20 strengthening pandemic preparedness and response=94 by Dr. Kumnuan = Ungchusak,=20 Director, Bureau of Epidemiology, Department of Diseases Control, = Ministry of=20 Health, Thailand. His = slides,=20 posted on the WHO website, portray the involvement of the Cabinet of = Thailand=20 via the National Avian Influenza response committee, which in turn = interacts=20 with the Ministry of Agriculture/Department of Livestock Development = (DLD), the=20 Ministry of Health, other ministries and the private sector. The National response = committee in turn=20 oversees the Government=92s Avian Influenza Operation Center and = coordinates with=20 both the DLD and MOPH operation centers that oversees the animal and = human H5N1=20 issues, respectively. The = budget=20 for the National Strategic Plan on Avian Influenza and Plan for Pandemic = Preparedness is $105 million.

With=20 regard to vaccines against H5N1, Webster and Hulse (Nature May 26, 2005. = p. 416)=20 observed that =93Thailand is now investigating the use of flu vaccines = for=20 backyard poultry, free-ranging ducks and fighting cocks (not commercial=20 poultry). This decision represents a major shift in policy. The use of = H5N1=20 vaccines for such =91open range=92 poultry is a prudent step, and should = be=20 encouraged in other countries in the region=94. No H5N1 vaccine studies = in humans=20 have been initiated to date in Thailand, although key discussions have = been=20 reported.

Daniel=20 R. Lucey, MD, MPH

Director,=20 Center for Biologic Counterterrorism and Emerging = Diseases

Department=20 of Emergency Medicine

Washington=20 Hospital Center

Adjunct=20 Professor of Microbiology and Immunology

Georgetown=20 University School of Medicine

Washington,=20 DC

e-mail:=20 Daniel.R.Lucey@Medstar.net=