Making the world better, one answer at a time. a superbug is a micro-organism that is resistant to most anti-biotics. the superbugs in recent history are imune to all anti-biotics,except one.
Both electronic and paper versions of Series I savings bonds are purchased at face value and earn interest until they are redeemed or reach maturity. You must hold Series I bonds for at least 12 months before redeeming them. Series I savings bonds will continue to earn interest for up to 30 years. They will cease paying interest once they have matured.
After 30 years, these bonds stop earning more interest. A $50 Series EE savings bond with a picture of President George Washington that was issued in January 1986 was worth $113.06 as of December. The bond will earn a few more dollars in interest at the next payment in January 2016.