This time last year Hong Kong’s SFH (Secretary of Food & Health), Dr. Ko Wing-man was taking a lot of heat from mainland Chinese officials over his insistence on performing both serological and PCR spot checks on shipments of imported poultry from neighboring provinces (see Dr. Ko Wing-man On H7N9 Testing Of Poultry).
While serological tests can determine if a bird has ever been exposed to and infected by a specific virus (very handy for viruses like H7N9 that produce no symptoms in birds), PCR testing must be used to determine if a bird is actively infected, and able to spread the virus.
Mainland officials have lobbied extensively against serological testing, feeling that a positive result would unfairly malign their poultry industry, and cause unnecessary culling of their product.
In the past 24 hours, a new batch of poultry arrived in Hong Kong and a handful of tested samples showed a positive result via serology, but negative by PCR. The positive serological results were viewed (rightfully so) as a red flag, which led Hong Kong to perform PRC testing on a larger number of birds, and last night the results were announced (see Imported Poultry PCR Positive For H7 Avian Flu).
Today Hong Kong is busy culling birds, and doing contact tracing and surveillance on those people who may have been exposed to infected birds. Two reports, first a statement by Dr. Ko Wing-man on the situation, followed by a progress report on local contact tracing efforts.
Following is the transcript of remarks made by the Secretary for Food and Health, Dr Ko Wing-man, at a media session on result of H7 Polymerase Chain Reaction (PCR) tests (genetic testing) of imported live chickens at the lobby of West Wing, Central Government Offices, this morning (December 31):
Reporter: (On the testing result of samples from a consignment of imported live chickens)
Secretary for Food and Health: On December 30, the Government found in a consignment of imported live chickens a number of samples tested positive in H7 avian influenza (AI) serology tests, whilst all swab samples collected from the same consignment of live chickens were tested negative in H7 Polymerase Chain Reaction tests. According to our risk management mechanism, we collected 120 additional swab samples from the same consignment of live chickens to conduct PCR tests. Shortly before now, the results were back. A number of samples were tested positive for H7 AI. Accordingly, we kicked off a number of public health measures to prevent the risk of spreading of H7N9 virus.
Firstly, the Agriculture, Fisheries and Conservation Department (AFCD) has declared the Cheung Sha Wan Temporary Wholesale Poultry Market as an infected place. It will be closed for 21 days. This will mean that supply of live poultry from the Mainland will also have to be suspended for the same period of time. After the 21-day suspension period, the index registered farm of this particular consignment of poultry has to be verified that it is safe in terms of bio-security measures before resuming supply of live chicken to Hong Kong.
AFCD will also arrange to cull all the live poultry, around 15 000 in total, in the Cheung Sha Wan Temporary Wholesale Poultry Market, starting this morning.
AFCD will then conduct inspections and collect additional samples for testing from all of the 29 registered live poultry farms in Hong Kong to ensure that they are not affected by H7 AI. We will then channel the local live chickens to the Ta Kwu Ling Checkpoint before they could be dispatched to the retail points.
Reporter: (On whether the Mainland authorities could step up their inspections at poultry farms)
Secretary for Food and Health: Hong Kong Government is always in very close collaboration with the relevant Mainland authorities. Our Mainland counterparts have been doing a lot in terms of safeguarding the health of live poultry to be supplied to Hong Kong. In fact, the supply chain of live poultry for Hong Kong is entirely segregated from other live poultry on the Mainland. You are right that this is not the first time that we have detected a positive H7 AI specimen from the live poultry supplied from the Mainland. This time is special. It is the first time that we have utilised the serology tests which helped us in detecting a batch of live poultry affected by H7 virus.
(Please also refer to the Chinese portion of the transcript.)
Ends/Wednesday, December 31, 2014
Issued at HKT 09:23
The Centre for Health Protection (CHP) of the Department of Health today (December 31) reported the latest updates on contact tracing after samples of live chickens imported from the Mainland tested positive for avian influenza A(H7) virus, and again urged the public to maintain strict personal, food and environmental hygiene both locally and during travel.
In collaboration with the Food and Environmental Hygiene Department and the Agriculture, Fisheries and Conservation Department, the CHP's epidemiological investigations have so far identified one close contact who is a poultry worker at Cheung Sha Wan Temporary Wholesale Poultry Market (CSWTWPM), and 77 other contacts including a lorry driver who transported the involved consignment of live chickens, poultry workers and staff at CSWTWPM and Man Kam To Animal Inspection Station, and workers involved in the poultry culling operation.
The CHP is tracing these contacts and will monitor their health conditions. Among them, a member of staff at CSWTWPM developed sore throat and his specimen tested negative for influenza A virus.
"Enhanced surveillance of suspected human cases in public and private hospitals is ongoing," a spokesman for the CHP remarked.
"Poultry workers, who have prolonged exposure to live poultry, might have higher risks of contracting the virus from infected poultry and hence increased risks of genetic reassortment of the virus. Poultry workers have been recommended by the CHP's Scientific Committee on Vaccine Preventable Diseases as one of the priority groups and have been covered in the Government Vaccination Programme under which they are eligible for free influenza vaccination. We advise them to get vaccinated early as it is one of the effective means to prevent influenza-associated complications and hospitalisations," the spokesman added.
Letters to doctors and hospitals will be issued to alert them to the latest situation.
The National Health and Family Planning Commission and the health authorities of Guangdong and Macau have been informed.
Poultry workers and cullers in doubt may call the CHP's avian influenza hotline (2125 1111) for enquiries and it operates from 9am to 6pm.
Ends/Wednesday, December 31, 2014
Issued at HKT 18:11