To be effective, most vaccines require a series of injections over weeks or months, constant refrigeration, and sterile syringes and needles to guard against the transmission of HIV, hepatitis, and other illnesses.
For parents and children in poor countries, these are serious obstacles to immunization. They may live hours or even days away from the nearest health clinic. Their villages may not have reliable electricity. And if their clinic lacks sterile equipment on the day they arrive for immunization, children miss out on vaccines that have the potential to save their lives.
New discoveries in chemical engineering may lead to childhood vaccines that overcome these obstacles. Researchers are working on vaccines that can be sprayed into the nose or mouth. They're developing formulations that stimulate stronger immune responses so that a single dose is sufficient. And they are working on inexpensive compounds that can be added to vaccines to preserve their potency after exposure to high temperatures.
The overall goal for poor countries is to eliminate diseases that were conquered in rich countries decades ago — diseases that still kill about 1 million children worldwide every year.
