Each year, 27 million children in poor countries do not receive basic preventive vaccines. As a result, serious diseases that were eliminated long ago in industrialized countries remain widespread in the developing world and cause more than 1 million child deaths annually.
Many of today’s childhood vaccines still require:
- Multiple dosages: Most vaccines must be given multiple times over weeks or months, posing a hardship for families who must travel long distances to the nearest health clinic.
- Refrigeration: Most vaccines must be constantly refrigerated, and many communities lack electricity. In 2007, an estimated 151 million vaccine doses delivered to developing countries will spoil without proper refrigeration.
- Delivery by injection: Most vaccines are delivered by injection, which increases the risk of transmitting HIV, hepatitis, and other infections through unsterile or reused syringes and needles. Needle-free vaccines could prevent an estimated 500,000 serious infections in 2007.
Recent advances in chemical engineering and other scientific disciplines could lead to a new generation of childhood vaccines that are effective after a single dose and do not require refrigeration or needles.