URUMQI - Xinjiang is at the frontline of preventing the import of wild poliovirus and maintaining China's polio-free status, a public heath official has said.

"Polio eradication worldwide has reached the final stage, but Xinjiang is still at a high risk of wild poliovirus," Wang Yu, director of the Chinese Center for Disease Control and Prevention, told China Daily on the sidelines of a two-day international workshop on polio eradication, which ended on Friday in Urumqi, capital of Northwest China's Xinjiang Uygur autonomous region.

Of the four polio-endemic countries in the world, Afghanistan, India, Nigeria and Pakistan, Xinjiang neighbors three.

In 2006 and 2010, wild poliovirus cases were found in Myanmar, Russia and Tajikistan, escalating the risks of future outbreaks in Xinjiang and China, Wang said.

"China has been polio-free for 11 years. In a globalized world where viruses know no boundaries, international leadership and collaboration are vital to the success of the global effort to eradicate polio," he said.

Since the 2010 outbreak in Tajikistan, Xinjiang's health department has enforced "stringent polio immunization requirements" for travelers crossing its border.

"We collect stool samples from children under 15 who enter Xinjiang, take their temperatures and make detailed records, all in a bid to stop wild poliovirus importation," said Fu Liping, director of the region's epidemic prevention office.

This year and in 2010, supplementary immunization activities involving 5.6 million doses of vaccine were held for children who were from 2 months old to 4 years old, according to official statistics.

A total of 422 immigrant children from Tajikistan, Pakistan, Afghanistan and other neighboring countries received Oral Poliomyelitis Vaccine immunization and Acute Flaccid Paralysis surveillance in Xinjiang in 2010 and 2011.

The regional health department also held an Oral Poliomyelitis Vaccine immunization coverage survey and sero-survey for antibody levels among children under 5 in four border cities.

The recent influx of wild poliovirus has been "unexpected," Wang said. "We will therefore never relax our vigilance against future polio outbreaks."

He also said the latest wild poliovirus infection in China occurred in Qinghai in 1999.

Projects to maintain a polio-free border area are being conducted in Yunnan province, Xinjiang and Tibet autonomous regions. Risk assessments on wild poliovirus importation and simulated outbreaks have been conducted in all three areas to raise public awareness.

"The situation in Myanmar is fragile. We had polio eradication in 2003, but we lost again in 2007, since wild poliovirus was imported," said Htar Lin in Myanmar's disease surveillance office.

Polio is an acute infectious disease spread from person to person, primarily via the fecal-oral route. When entering the central nervous system, the virus will infect motor neurons, leading to muscle weakness and acute flaccid paralysis.

"Polio virus is like a devil locked in a box. Once we relax our surveillance, the devil will come out and harm children," Wang said. "China is working closely with other countries and I firmly believe, in the near future, every child in the world will say goodbye to polio."

China Daily

(China Daily 07/23/2011 page4)