While the HPAI virus afflicts animals rather than humans, there have been isolated cases of animal-to-human transmission in instances characterised by close and repeated human interaction with infected poultry. The migration of the virus from poultry to humans typically occurs through human contact with fecal materials, and while a high mortality rate has been observed in infected persons, there is no evidence that HPAI can be transmitted amongst humans like the common human flu. However, the World Health Organisation (WHO) has expressed concern that HPAI, and particularly the H5N1 strain found in several Asian countries, could mutate into a form that is highly infectious to humans and spreads easily from person to person. Such an occurrence could produce a pandemic of potentially serious consequences.

While the more serious H5N1 strain has never been found in the US, the country has suffered three known outbreaks of HPAI over the past century, in 1924, 1983-1984, and 2004. The 1924 outbreak, involving the H7 strain of HPAI, was detected in and eradicated in East Coast live bird markets. The 1983-84 outbreak, involving the H5N2 strain, resulted in the destruction of approximately 17 million chickens, turkeys, and guinea fowl in the north-eastern US. The H5N2 strain resurfaced in the southern region of the country in 2004, but because of the quick response and close co-operation among federal, state, and local authorities the outbreak was limited to only one flock.

Mindful of the hazardous effects of the H5N1 strain of HPAI, the US established a temporary prohibition on 4 February 2004 on the importation of unprocessed bird and poultry carcasses, parts, and products from countries where the H5N1 strain has been found to exist, namely Cambodia, mainland China, Hong Kong, Indonesia, Japan, Laos, South Korea, Thailand, and Vietnam, except for approved shipments for scientific, educational, or research purposes. Hong Kong was removed from this list on 10 March 2004, while Kazakhstan, Malaysia, Romania, Russia, and Turkey were added in 2005.

Poultry imports from these countries had been tightly controlled well before the H5N1 prohibition became effective due to the presence of Exotic Newcastle Disease (END). Only a handful of countries in Europe, Latin America, and Oceania are considered free of END. The restrictions listed below apply to END-affected countries, including Hong Kong. These restrictions also apply to mainland China but they are currently superseded by the H5N1-related embargo.

• Carcasses of game birds may be imported if eviscerated, with heads and feet removed. Viscera, heads, and feet removed from game birds are ineligible for entry into the US.

• Carcasses, or parts or products of carcasses, of poultry, game birds, and other birds may be imported for consignment to any museum, educational institution, or other establishment which has provided the US Department of Agriculture (USDA)'s Animal and Plant Health Inspection Service (APHIS) with evidence that it has the equipment, facilities, and capabilities to store, handle, process, or disinfect such articles so as to prevent the introduction or dissemination of END into the US.

• Carcasses, or parts or products of carcasses, of poultry, game birds, and other birds, may be imported if packed in hermetically sealed containers and if cooked by a commercial method after such packing to produce articles which are shelf stable without refrigeration.

• Carcasses, or parts or products of carcasses, of poultry, game birds, and other birds may be imported if thoroughly cooked, and if, upon inspection by a USDA representative at the port of arrival, the carcasses or parts or products thereof have a thoroughly cooked appearance throughout.

• Poultry carcasses or parts or products of poultry carcasses that originated in a region considered to be free of END and are processed (cut, packaged, and/or cooked) in a region where END is considered to exist may be imported under certain conditions.

• Carcasses or parts or products of carcasses, of poultry, game birds, and other birds that do not otherwise qualify for importation may be imported only if the importer applies to and is granted a permit by APHIS authorising such importation. Permission will be given only when APHIS determines that such importation will not constitute a risk of introduction or dissemination of END into the US.

One of the questions that has confounded US textile and apparel importers is whether feathers and down can be imported without restriction from countries affected by the H5N1 strain of HPAI. A fact sheet issued by APHIS confirms that finished products containing feathers and/or down imported ready for retail sale/commercial distribution, such as mattresses, jackets, and pillows, can be imported into the US without an APHIS veterinary import permit, even if those shipments originate in a country where H5N1 has been deemed to exist. Shipments are however subject to inspection at the port of entry to verify that the feathers and/or down are clean, dry, and free from blood, skin, and manure. It would therefore be advisable to have a statement by the manufacturer demonstrating that the feathers and/or down have been disinfected and indicating the method of disinfection.

According to the International Down and Feather Testing Laboratory (IDFL), "if a virus of any type did exist in a raw down and feather shipment, the washing, sterilizing, and drying procedures are sufficient to destroy it." Down is first washed with a detergent to remove all dust, dirt, and organic matter, and the washed down is subsequently steamed at 120-130^ocentigrade for thirty minutes. It has been shown that the avian influenza virus can survive only 2-3 minutes at 56^oC, so the washing and steaming process detailed above would be more than sufficient to eradicate any trace of a virus in a down/feather shipment.

The US Federal Trade Commission (FTC) notes that one of the ways to determine the cleanliness of feather and down filling is achieved through the measurement of the oxygen number. Cleanliness should be consistent with an oxygen number of less than 10, no matter how that measurement is taken. IDFL also recommends that shipments be tested for turbidity to determine the amount of dust in feather and down products. Clean products must have a turbidity greater than 300 mm.

Bulk shipments of feathers/down from mainland China require a permit from APHIS prior to importation into the US. The feathers/down need to be treated prior to exportation (i.e., washed at 130^ocentigrade for at least 30 minutes). The importer would then need certification that this treatment has been undertaken as a basis for requesting an APHIS permit. Since Hong Kong is not currently included in the list of H5N1-affected countries, it can export bulk shipments of feathers/down to the US without an APHIS veterinary permit. These shipments should be accompanied by proof of country of origin of the birds from which the feathers were sourced to ensure that they did not originate from an H5N1-affected country. An official government certificate confirming that the feathers/down were sourced in Hong Kong constitutes sufficient evidence of origin.

Growing concerns over avian influenza led President Bush to establish a National Strategy for Pandemic Influenza (NSPI) on 1 November. This strategy has three fundamental objectives and is sustained by three pillars.

NSPI Objectives

• Stopping, slowing, or otherwise limiting the spread of a pandemic to the US.
• Limiting the domestic spread of a pandemic and mitigating disease, suffering, and death.
• Sustaining infrastructure and mitigating impact to the economy and the functioning of US society.

NSPI Pillars

• Preparedness and communication, including planning for a pandemic, communicating expectations and responsibilities, producing and stockpiling vaccines, anti-virals, and medical material, establishing distribution plans for vaccines and anti-virals, and surveillance, advancing scientific knowledge and accelerating development.
• Using surveillance and detection methods to rapidly report any outbreaks and limit spread.
• Containing and responding to outbreaks by leveraging US medical and public health surge capacity, sustaining infrastructure, essential services, and the economy, and ensuring effective risk communication.

The NSPI does not in any way change the existing regulatory framework for the control and processing of poultry and poultry products. However, it is possible that CBP may exercise additional scrutiny to ensure that H5N1-infected animals do not enter the flow of commerce. A CBP official noted on 1 December that CBP will soon conduct a practical exercise to evaluate options and further develop policies for regulating commerce in the event of an avian influenza-related problem or incident.