Madrid - International tourist numbers surged by 5.2% to nearly half a billion people worldwide in the first half of 2013, beating earlier expectations, the United Nations' World Tourism Organisation said Monday. The growth was higher than expected, with 494 million international tourists spending at least one night abroad in the first six months of the year, it said in a report of preliminary results for the period. As a result of the "robust" performance, the organisation said it was boosting its 2013 forecast. After originally tipping growth of three-four percent for the whole year, it now expected the increase to be at the higher end of that range "or to slightly exceed it". Europe enjoyed growth of 5.1% in international tourist numbers in the six months, it said. But results were weaker than anticipated in the Americas, which posted growth of just 2.2%. International tourist numbers grew 3.1% in North America but South America reported growth of just 0.3% and the Caribbean had growth of a meagre 0.1%. In Africa, international tourist arrivals rose by 3.8%.