This is the VOA Special English Health Report , from voaspecialenglish.com | http United Nations estimates that the world reached seven billion people on October thirty-first. No one can be sure. The United States Census Bureau does not expect the seven billionth baby until March. Populations are growing faster than economies in many poor countries in Africa and some in Asia. At the same time, low fertility rates in Japan and many European nations have raised concerns about labor shortages. Popu...