The name coupon arose because in the past, paper bond certificates were issued which had coupons attached to them, one for each interest payment. On the due dates the bondholder would hand in the coupon to a bank in exchange for the interest payment.
Hib vaccine. Haemophilus influenzae type B vaccine is a vaccine used to prevent Haemophilus influenzae type b (Hib) infection. In countries that include it as a routine vaccine, rates of severe Hib infections have decreased more than 90%. It has therefore resulted in a decrease in the rate of meningitis, pneumonia, and epiglottitis.
Before Hib vaccine, Hib disease was the leading cause of bacterial meningitis among children under 5 years old in the United States. Meningitis is an infection of the lining of the brain and spinal cord. It can lead to brain damage and deafness.