Three Palestinians in the West Bank have died in the past week from the H1N1 influenza strain known as swine flu, the Palestinian health ministry said on Thursday.

"There were three deaths in the past week, and more than 50 people sickened by the virus," Assad Ramlawi, the ministry's director general of health care for the West Bank, told AFP.

He said the deaths occurred in the northern cities of Jenin, Qalqilya and Tulkarem, but played down the significance of the fatalities.

"The situation is not out of the ordinary. This virus spreads at the beginning of winter season," he said, adding that those who had died "had weak immune systems, which is what caused their deaths."

The health ministry said medical staff had been trained to detect and treat the virus.

The virus has affected Israel and the Palestinian territories in the past, killing dozens of people.