NIGERIA is adding South Africa to its "red list" of countries for which there are stringent restrictions for arriving passengers, officials said during a briefing. Nigeria is introducing the restrictions due to the spread of the Delta variant in South Africa, Chikwe Ihekweazu, the head of the Nigeria Centre for Disease Control, said. The country joins India, Brazil and Turkey on the list. "In Nigeria, we haven't found the Delta variant yet," Ihekweazu said during the briefing. Non-Nigerian passport holders and non-residents who visited the countries on the list within 14 days are barred entry from Nigeria, while passport holders…