Email from Dr Ruth Watkins Feb 16 2007
The international trade legal, illegal, legal but poorly monitored, legal but cheating on the paperwork etc is just brilliant for spreading agents which are highly infectious round the world (if not attendant mosquitoes, midges, fleas and ticks etc.). It can happen innocently and unintentionally. Only a tiny amount, even one infectious particle or virion, can be sufficient to infect a susceptible host such as a fowl with HPAI H5N1.
I expect sheep 'breeds' were brought into the UK by the successive incomers from neolithic farming onwards with their attendant diseases. In the realm of human infectious disease as you know infection is taken along with the moving humans. In the case of humans we cannot prevent fairly free movement except in special circumstances because of disease e.g.SARS and of course we don't aim to cull every infected human. Bacteria as well as viruses are carried around the world. The latest strain of Clostridium difficile was brought over from Canada it seems - this is a new strain with a tenfold increase in toxin production. Now it is here in our hospitals too.
I can't see any reason for there being all this world trade in live and raw dead animals and their products. Perhaps cooked meat products. Perhaps occasional introduction of breeds to improve nutrition in other countries but with extra care and quarantine. Semen should be something that can be subject to thorough verification, quarantine and testing - i.e. being held in liquid nitrogen for 6 months while all is checked out.
This would be very hard on New Zealand that depends on export more than any other country I can think of - and has been accused of very little. Perhaps the review will have to be selective; address the spread of H5N1 by poultry, address the spread of PMWS etc. the export on cold ships of hung lamb carcasses and beef carcasses might be exempt. I am out of my depth on the territory of trade. However, I would have thought we cannot allow H5N1 and PMWS to spread unchecked.
Politics and farming interests interfere with virology sleuthing. I do commend Ian Brown ( chief avian virologist at VLA) for sticking to his guns over the recent H5N1.
Archive July and August 2005
Archive Jan 2005 - July 2005
Archive Oct 2004 - Dec 2004
Archive August 2004 -October
OTHER WARMWELL ARCHIVES(opens in new window)