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.
A Series EE savings bond continues to earn interest for up to 30 years if it is not redeemed. Even after a bond reaches its face amount at the 20 year point, interest is still credited to the value. Savings bonds older than 30 years should be redeemed as they are no longer earning interest.