Public health assessment Avian flu A(H5N1) situation Feb 9, 2004

Human infections with Avian influenza YearPlaceSubtypeCasesDeaths 1997HKH5N HKH9N HKH5N NetherlandsH7N HKH9N (as of Feb 6) Viet Nam Thailand H5N

Areas reporting avian influenza H5 outbreaks in poultry VietNam Thailand South Korea Japan Cambodia Taiwan (H5N2) Laos Indonesia China 廣西, 湖北, 湖南, 廣東, 雲南, 安徽, 江西, 陝西, 甘肅, 河南, 浙江

Transmission in current outbreak Exposure to infected poultry predominant Man-to-man transmission could not be ruled out in one family (Viet Nam) However, genes all avian in nature Positive PCR nasal from 2 pigs (Viet Nam); serology result awaited

Strategies – affected areas Stamp out infected poultry PPE and vaccination for poultry workers, monitor health Vaccination of poultry has to be coupled with biosecurity and surveillance Processed poultry products and eggs do not pose risk to pubic health

Strategies – Hong Kong Human Surveillance Influenza vaccination for poultry workers Communications with professionals and public Liaison with mainland, WHO, and other countries Contingency planning Poultry Surveillance Vaccination Biosecurity Import control Segregation Rest days Hygiene requirements in markets

Case definition A person with Positive viral culture for influenza A (H5), or Positive PCR for influenza A (H5), or > 4-fold rise in H5 specific antibody titer

Criteria for reporting (1) Person with acute respiratory illness, characterized by fever (temp > 38C) and cough and/or sore throat, AND EITHER Contact with case of influenza A (H5) during the infectious period, or Recent (less than 1 week) visit to a poultry farm in an area known to have outbreaks of HPAI, or Worked in a lab that is processing samples from persons or animals that are suspected from HPAI infection

Criteria for reporting (2) Person with severe pneumonia caused by influenza A and had contact with live birds/poultry within 1 week before onset of illness

Reported numbers 14 reports received as of Feb 9, from HA hospital 3 from private hospital 5 from public and private clinics

Laboratory investigations (1) Patient fulfilling the reporting criteria should be reported to DH and investigated for H5 infection (e.g., H5 PCR on an NPA specimen) Refer to A&E through ambulance If patient refuses transfer to A&E, inform DH which will take follow up action Patient will be admitted or given 3 days sick leave until lab result comes back

Laboratory investigations (2) Patients not fulfilling the reporting criteria do not require routine H5 test Doctor may perform rapid test on the above patients (e.g., Directigen) If Directigen positive for influenza A, may send to DH Public Health Laboratory Center for culture/typing

What if local human case Epidmiological investigation, esp. Mode of spread Man-man transmissibility Review reporting criteria and heighten surveillance ? Poultry culling If efficient man-to-man transmission occurs Contingency arrangements of medical services ? Presumptive treatment for influenza-like-illness

Outlook FAO/OIE/WHO, Feb 3-4: Outbreak is evolving, expected to expand in geographical distribution and incidence. Not under control yet. Future outlook ? Epidemic under control over next few weeks, no more human cases ? Avian flu returns to this region now and then ? New strain evolves capable of efficient man-man transmission

Useful links and resources WHO guidelines for the collection of human specimens for laboratory diagnosis of influenza A/H5 infection pecimens/en/ WHO guidelines for the storage and transport of human and animal specimens for laboratory diagnosis of influenza A/H5 infection rt/en/ Infection Control Guidelines for Health Care Facilities for Highly Pathogenic Avian Influenza virus (HPAI)

Useful links and resources Guidelines for the use of seasonal influenza vaccine in humans at risk of H5N1 infection uidelines/seasonal_vaccine/en/ UPDATE ON AVIAN INFLUENZA IN ANIMALS IN ASIA (from World Organization for Animal Health) LUENZA/A_AI-Asia.htm

Useful links and resources Hong Kong Government ’ s Avian Flu website htm. Department of Health ’ s website

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Recent trend of human influenza Hong Kong: Human influenza activity stable so far 2 institutional outbreaks (Jan 1-24, 2004) Both Panama and Fujian strains detected, no abnormal increase World: Rise in central and eastern Europe, Italy and Japan Downward trend in US and some parts of Europe