Eleven people have died as a result of heat stroke in South Africa, authorities said on Sunday.All the deaths were reported in the North West province, Xinhua quoted the provincial health department as saying.The deceased were aged between 22 and 58 years, department spokesperson Tebogo Lekgethwane said.Some people suffering from heat stroke have been admitted to hospitals, he said.The Mahikeng Provincial Hospital alone accepted 16 people over the past three days.As a persistent heat wave continues unabated, the North West province has been declared a drought area under the Disaster Management Act.The heat wave has also worsened dry conditions in Free State and Limpopo -- both maize-producing regions.The dry conditions are believed to be caused by cyclones in the Indian Ocean which have absorbed the moisture from the subcontinent's interior.Crop farmers in the north-west have suffered an estimated loss of 4.3 billion rand (about $269 million) due to the severe drought.