International tourist numbers surged by 5.2 percent to nearly half a billion people worldwide in the first half of 2013, beating earlier expectations, the United Nation\'s World Tourism Organisation said Monday. Some 494 million international tourists spent at least one night abroad in the first six months of the year, the Madrid-based agency said in a report of preliminary results for the period. As a result of the \"robust\" performance, the WTO said it was boosting its 2013 forecast. After originally tipping growth of three to four percent for the whole year, it now expects the increase to be at the higher end of that range \"or to slightly exceed it\". Europe enjoyed growth of 5.1 percent in international tourist numbers in the six months, it said. The Asia-Pacific region reported growth of 6.2 percent including an 11.6 percent surge in tourists going to Southeast Asia. But results were weaker than anticipated in the Americas, which posted growth of just 2.2 percent. International tourist numbers grew 3.1 percent in North America, but South America reported growth of just 0.3 percent and the Caribbean had growth of a meagre 0.1 percent. In Africa, international tourist arrivals rose by 3.8 percent. In the Middle East, tourist numbers soared by 12.9 percent, but these figures should be viewed \"with caution\" because of uneven results and limited data, the report said.