BRUSSELS (AP) — The greatest influx of people into Europe in decades is not just a humanitarian emergency, but also a potential stroke of luck for many countries facing the economic threat of an aging population. By contrast, weaker economies like Greece and Italy will take years, even decades, to see positive effects as they struggle to create jobs — though they too face the threat of a demographic time bomb. Daimler CEO Dieter Zetsche, whose German company makes Mercedes-Benz cars and trucks, made the case this week: "To take into Germany more than 800,000 people who need our help is without a doubt a Herculean task, but in the best case, it can also be the basis for the next German economic miracle." Sweden, which last year received 80,000 asylum seekers, second highest in the EU behind Germany, also views the newcomers as a net gain, though up-front costs may be stiff. Because we have an aging population," Kristina Persson, minister for Nordic cooperation, said, "we have to replace those who leave the labor market. Some states, including Poland, are worried not only about the immediate costs of welcoming refugees, but are also mindful of popular fears that foreign-born Muslims might not easily blend into society or that terrorists could lurk among them. A migration expert at the Organization for Economic Cooperation and Development in Paris, Jean-Christophe Dumont, said that it's costlier up front to integrate refugees than other categories of immigrants, because they often need language and vocational training as well as treatment for physical injuries or psychological trauma.