At least 10 people in northwestern China have contracted a highly infectious strain of polio, in the first outbreak of the disease in the country for 12 years, a United Nations group said Thursday.

Six children and four adults in the Xinjiang region have been diagnosed with the wild poliovirus type 1 (WPV1) strain, a spokeswoman for the United Nations Children's Fund in China told AFP.

Tests showed that WPV1, which is more contagious and more likely to cause paralysis than other types of polio, shared similar characteristics to the strain currently circulating in Pakistan, which borders Xinjiang, Liu Li said.

UNICEF is working with Chinese authorities to handle the outbreak, the first in China since 1999, she said.

"Up until today the Ministry of Health has confirmed 10 cases of WPV1. Six of the cases are in children under five years of age and four of the cases are in adults," Liu said.

There has been one reported death so far, the health ministry said on its website, adding that it was "closely monitoring the outbreak".

The ministry has dispatched three teams of experts to the remote region, which is home to the mainly Muslim Uighur minority, and vaccinated "priority groups".