Diabetics who are infected with TB become ill with the disease at three times the ratio of the general population because their immune systems are compromised, said Dr. Seaworth, who is also a professor of medicine at the University of Texas Health Science Center-Tyler.

WSJ: TB's Global Resurgence Amplifies U.S. Risk

However, Carnegie notes that the fiscal budgets of many oil-exporting countries were rising prior to the citizen revolution due to a lack of non-oil revenues, rapid population growth and generous welfare systems.

FORBES: Oil Producers Keen To Defend Crude Price

Ill-designed pension systems magnify the effect of population ageing by creating incentives for people to retire ever earlier.

ECONOMIST: Time to grow up | The