Farewell to polio in the Western Pacific
Tony Adams1
29 October 2000 will go down in history as the day on which the world celebrated the end of poliomyelitis in the Western Pacific Region a vast area stretching from the western borders of China to the eastern reaches of Polynesia, comprising 37 countries and areas and a quarter of the worlds population. This matches the achievement announced on 20 August 1994 when the Pan American Health Organization declared the Americas to be polio-free. Now two of the World Health Organizations six regions have been declared polio free, meaning that in them the transmission of indigenous wild poliovirus has been totally stopped.
In 1990 the independent International Commission for the Certification of Poliomyelitis Eradication in the Americas was established to provide an impartial and critical overview of the eradication process and its results. WHO set up the Global Commission for the Certification of Poliomyelitis Eradication in 1995. In its turn, the Western Pacific Regional Office of WHO (WPRO) established the Regional Commission for the Certification of Poliomyelitis Eradicationa (RCC) and this body met for the first time in 1996 in Australia.
Four years later, at its sixth meeting held in Japan, the RCC was able to conclude that the circulation of indigenous wild poliovirus had ceased throughout the Region. Since the last indigenous case had been detected in Cambodia, on 19 March 1997, a period of over three years had elapsed, during which conditions of high quality surveillance had been maintained throughout the region. The RCC met six times during those three years, and watched the number of cases of polio steadily drop in response to national, sub-national and targeted immunization activities conducted in endemic and recently endemic countries.
WHO WPRO worked with national governments to work out special tactics to reach underserved populations in which wild poliovirus continued to circulate despite national immunization activities. In intensive operations targeting the last known areas of wild poliovirus circulation in several countries, mobile teams went from house to house and boat to boat to immunize mobile and difficult-access populations.
As cases declined, the number of specimens from acute flaccid paralysis (AFP) cases subjected to virological examination rose dramatically, providing ever-increasing confidence in the surveillance system. The regional polio laboratory network, established by WHO as part of the global network, ensured that virological examination of samples from suspected polio cases was undertaken quickly and effectively.
To give an idea of how dramatic the fall in the number of poliomyelitis cases has been, in 1990 nearly 6000 cases were reported in the region, and since the reporting system was incomplete the true number of new cases per year was estimated to be closer to 60 000. By 1993, with a complete and reliable surveillance system in place, this had dropped to 1147. For the remaining years of the 1990s the figures were: 744 in 1994, 481 in 1995, 198 in 1996 and, finally, 9 in 1997.
The Global Commission has set criteria and guidelines for the certification process that have to be followed by the Regional Commissions. The Western Pacific RCC spelt out these criteria in detail in order to make our expectations as clear as possible to the National Certification Committees as they prepared their final documents. Between RCC meetings many members had the opportunity to observe immunization activities in action, reviewing AFP surveillance activities and meeting with National Certification Committees. The sheer effort, enthusiasm and organization that went into the national immunization days left an indelible imprint on the minds of those of us fortunate enough to have observed them. Most recently, Chinas remarkable response to the importation of wild poliovirus from a neighbouring endemic country into remote Qinghai province was truly impressive. The response to this emergency which could happen anywhere in the world at any time until global eradication is attained cost the Chinese Government millions of dollars, and thousands of health workers enormous effort. The world should pay heed to this experience and use the expensive lessons learnt to push for a rapid completion of the eradication effort in the regions that still harbour wild poliovirus. The Western Pacific Region shares borders with several countries in other regions where wild poliovirus is still circulating. All polio-free countries must therefore maintain the ability to detect and respond to imported cases.
The Global Commission has set as one of its requirements for global certification the destruction or high security containment of all biologically derived specimens that may contain wild poliovirus currently being held in laboratories and research institutes around the world. The RCC in the Western Pacific made evidence of significant progress towards containment a condition for regional certification, and such progress has been made.
It is impossible to name everyone who has made this victory in the Western Pacific possible. National ministry of health staff, many of whom have toiled for years in difficult and often dangerous conditions, have done the real work of poliomyelitis eradication. An international partnership, coordinated by WHO and including UNICEF, the governments of Australia, Canada, Finland, France, Italy, Japan, the Republic of Korea, Sweden, the United States of America, and Rotary International, and many others, has provided constant and well-coordinated support. Together with their national colleagues, the partners have not only helped to wipe out poliomyelitis but they have supported the strengthening of fundamental public health infrastructures across a significant part of the world.
The members of the Regional Certification Commission salute their work and thank them for their morale-boosting achievement, which gives us all hope that the global goal will be reached by 2005. 
1 Chairman, Regional Commission for the Certification of Poliomyelitis Eradication in the Western Pacific Region, National Centre for Epidemiology and Population Health, Australian National University, Canberra ACT 0200, Australia.
a Members of the Regional Commission for the Certification of Poliomyelitis Eradication in the Western Pacific (RCC): Dr Anthony Adams (Chairman), Dr Carlyle Guerra de Macedo, Dr Nguyen Dinh Huong, Dr Olen Kew, Dr Peter Patriarca (Rapporteur), Dr Aida Salonga, Dr Shudo Yamasaki (Vice Chairman), Dr Hui Zhuang.
Ref. No. 00-1037