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LCQ18: Avian influenza virus detection
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    Following is a question by the Hon Emily Lau and a written reply by the Secretary for Food and Health, Dr York Chow, in the Legislative Council today (June 25):

Question:

    Following the announcement on June 7 that some samples taken from the poultry stalls in Po On Road Market in Sham Shui Po were tested positive of the H5N1 avian influenza virus, the authorities still allowed the sale of live chickens in the remaining markets throughout the territory, and the number of live chickens involved was about 100 000.  The authorities took 63 environmental samples from a number of markets on the same day for laboratory tests, and confirmed on June 11 that eight of the chicken faecal samples were tested positive of the H5N1 avian influenza virus.  It was not until then that the authorities destroyed all live chickens in markets throughout the territory.  The Agriculture, Fisheries and Conservation Department (AFCD) cannot locate the source of the infected chickens in question or rule out the possibility that some of them were smuggled into the territory.  In this connection, will the Executive Authorities inform this Council:

(a) given that it has taken as long as five days before the results of the avian influenza virus tests carried out by AFCD were available, and during this period, members of the public might have been infected with the avian influenza virus as a result of consuming chickens carrying the virus but showing no symptom, or exposure to the market environment, whether the authorities will consider carrying out regularly the avian influenza virus rapid tests with results available in just one day, so as to detect the virus as soon as possible and thereby reduce the chance of the public being infected with the virus; if not, of the reasons for that;

(b) of the new measures to intercept the smuggling of chickens into the territory; and whether the Food and Environmental Hygiene Department will carry out surprise inspections on live poultry stalls in markets, so as to curb these smuggling activities; if so, of the details; if not, the reasons for that;

(c) given that AFCD has adopted measures in various areas to monitor avian influenza, and yet some samples taken from the poultry stalls in markets were tested positive of the H5N1 avian influenza virus, whether the authorities will review if there is any loophole in the mechanism for monitoring avian influenza; if they will not, of the reasons for that; and

(d) given that the Food and Health Bureau advised in November last year that to implement the proposal of central slaughtering of poultry, the authorities were preparing the tendering documentation for the poultry slaughtering and processing plant, conducting the environmental impact assessment concerned and exploring how to reduce the impact of the implementation of central slaughtering on the trade, and they planned to submit the legislative proposal concerned to this Council in early 2008, and as the H5N1 avian influenza virus was recently detected in a number of poultry stalls, of the latest progress of the above work and the timetable concerned?

Reply:

Madam President,

(a) Performing viral genetic analysis by the use of the Reverse Transcription Polymerase Chain Reaction techniques (RT-PCR) is commonly known as the rapid method to detect the H5N1 virus genomes and it requires a processing time of about four to eight hours.  However, according to the suggestions given by the World Animal Health Organization (OIE), the application of direct RT-PCR tests is to confirm if a disease is spreading following an outbreak, where infection is known or suspected.  All positive specimens must be tested by the use of embryonated egg inoculation for further confirmation.

    Currently, virus isolation by embryonated egg inoculation is the worldwide recognised accurate method for avian influenza virus detection and confirmation. According to the OIE guidelines on avian influenza testing, the specific pathogen free eggs must be incubated for at least four to seven days, with its allantoic fluid harvested for virus detection.  Allantoic fluid showing negative reaction is then passaged into another batch of egg for virus detection.  This method is generally applicable in an environmental surveillance system, so as to ascertain more accurately whether H5 and other viruses are present in the environment.  Therefore, the method of virus isolation by embryonated egg inoculation is applied in testing environmental swabs.  This is in line with OIE guidelines. 

    The Veterinary Laboratory of the Agriculture, Fisheries and Conservation Department (AFCD) has been accredited by the National Association of Testing Authorities, Australia (NATA) to provide animal disease surveillance and diagnostic services consistent with international standards.  All avian influenza testing is performed according to the diagnostic methods recommended by OIE.

(b) Relevant government departments, including the Customs and Excise Department (C&ED), AFCD, as well as Food and Environmental Hygiene Department (FEHD), have maintained close liaison and exchanged intelligence relating to smuggling of poultry.  Joint operations are also carried out at various land boundary control points from time to time to intercept poultry smuggling activities.  Besides, the C&ED has stepped up vigilance by increasing cargo inspection at all land boundary control points and during sea patrols, so as to combat poultry smuggling activities.  The C&ED has also strengthened cooperation with the Mainland Customs Authorities, including intelligence sharing and carrying out of joint anti-smuggling operations.

    Customs and police officers will inform the AFCD of any poultry smuggling activities detected.  The AFCD will then take appropriate prosecution actions against the offenders.  As part of its publicity and educational efforts, the AFCD also distributes publicity leaflets at various smuggling blackspots from time to time.  To strengthen its efforts in combating smuggling, the AFCD regularly distributes or sends by post the "Illegal Import of Animals/Birds Information Envelope" to traders so as to gather intelligence on smuggling activities.

    The FEHD officers conduct inspections on chicken stalls twice a day and check the receipts to ascertain the sources of live chickens kept in the chicken stalls from time to time.  Upon receipt of complaints or intelligence concerning chicken stalls involved in chicken smuggling activities, the FEHD will carry out investigation.  Over the past year (as at June 10), a total of 78 investigative actions were conducted by the FEHD intelligence team and no irregularities were found.

    Regarding the recent detection of avian influenza virus in the chicken faecal samples collected from the retail markets, the C&ED has conducted a special investigation with the AFCD and the FEHD to find out whether the incident is related to smuggled chickens and to step up anti-smuggling efforts.  C&ED officers have visited the markets and contacted the chicken traders to collect information, and distributed publicity leaflets calling on the trade and the public to provide information on poultry smuggling.

    In order to further combat poultry smuggling activities more effectively, the cooperation of the trade is of utmost importance.  If the trade can provide us with intelligence and information, this will greatly facilitate our anti-smuggling efforts.

(c) We have completed the review and announced the new measures on June 24, 2008.

(d) We have originally been preparing for the setting up of a Poultry Slaughtering and Processing Plant (the Plant).  We have also identified a site in Sheung Shui for the development of the Plant.

    Nevertheless, the Administration has decided to introduce legislative amendments to prohibit overnight stocking of live chickens at retail level.  The live poultry trade has also approached us at the same time on the ex-gratia payments for surrender of licences.  Implementation of central slaughtering is to achieve the objective of separating live poultry from humans so as to reduce risks posed by avian influenza.  We therefore need to review the necessity of developing the Plant, taking into account the situation after the implementation of the new measures and also the progress of the discussion with the trade on the buyout package.

Ends/Wednesday, June 25, 2008
Issued at HKT 16:38

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