Fidel Castro blamed the United States and other rich nations on Wednesday for policies that encourage an international brain drain of doctors and scientists from Africa and Latin America. "Encouraging this type of emigration has become an official state policy in a number of (developed) countries, which use incentives and procedures especially tailored to suit this end," Castro wrote in the latest of the essays he has been writing every few days. Castro cited a 2000 US law that increased the number of temporary work visas issued to highly qualified immigrants to entice them America's technology sector, and said Canada, Australia, Germany and the United Kingdom have similar measures. Castro said the "unjust policy" of the United States has deprived Cuba of 5.16 percent of the 805,902 professionals who have graduated since his 1959 revolution began. And he said claimed Africa, the Caribbean and Central America have fared worse, losing more than 30 percent of their college graduates.