Polio eradication has reached a major landmark with the two-year anniversary of the last case of polio in the Western Pacific Region.

According to the World Health Organization, which is leading the international effort to eradicate the disease, polio is unlikely to ever occur again in the most heavily populated WHO region which includes China.

Since the last case of polio was found in Cambodia on 19 March 1997 – a 15-month-old girl -- there has been no trace of wild poliovirus in the region. The highly infectious disease most commonly affects children under five and can cause paralysis in a matter of hours. Interrupting the spread of wild poliovirus among the population is key to the global eradication effort.

"We are out of the critical phase in this region," said Dr Bruce Aylward, Global Co-ordinator of WHO's Polio Eradication Initiative. "Today we celebrate this important date in the war against polio which brings us one step closer to the day when children no longer live at risk from this paralyzing disease."

Seven out of 30 countries in the Western Pacific Region were polio-endemic: Cambodia, China, Malaysia, Mongolia, Papua New Guinea, Philippines and Vietnam. Polio outbreaks occurred in the region as recently as the early 1990s with several thousand cases reported in China. The last case in China was found in 1994, following two years of intensified polio eradication activities.

WHO is spearheading the international effort to eradicate polio by the end of the year 2000. In 1991, the last case was found in the western hemisphere which was certified polio-free in 1994 after a three-year period of intensive surveillance. Only three major areas of transmission remain in the world: South Asia (Afghanistan, Pakistan, India), West Africa (mainly Nigeria) and Central Africa (mainly the Democratic Republic of the Congo).

As a result of mass immunization campaigns that reach hundreds of millions of children, the number of cases worldwide has fallen by almost 90 percent in ten years -- from 35,000 to 5,000 cases in 1999. Just a few vaccine drops guarantee a child life-long protection against the disease.

Speaking at a press conference held today in Manila, the Philippines, Dr Julian Bilous of the WHO Regional Office for the Western Pacific said: "Polio eradication will not only rid the world of polio and save the world US $1.5 billion annually but is also strengthening immunization services for prevention of other diseases.

"The legacy of this effort is strong national disease-reporting systems and well-trained health workers – all critical to effective disease prevention and control. Now that polio is gone from this region, we can adapt what we have learnt and concentrate on other diseases such as measles, malaria and TB."

WHO launched its global polio eradication initiative in 1988. Major partners are Rotary International, UNICEF, the Centers for Disease Control, and the governments of Australia, Canada, Denmark, Germany, Japan, the United Kingdom and the United States.

Polio eradication relies on four main strategies: high routine immunization coverage with Oral Polio Vaccine; National Immunization Days which vaccinate millions of children under five in a single day; effective surveillance for Acute Flaccid Paralysis and wild poliovirus; door-to-door immunization known as "mopping-up" campaigns.