vaccines- which protect against disease by assuring (ทำให้เชื่อมั่น)immunity-are widely and routinely given around the world. This practice is based on the idea that it is better to keep people from falling ill than to focus only on helping them recover (รักษาได้)once they are ill. Suffering, disability and death are avoided. immunization is thought to prevent two to three million childhood deaths each year. In addition, infection is reduced, strain on health-care systems eased, and is money is frequently saved that can be used for other health services.