Immunisation is the introduction of vaccines into our bodies so that antibodies will be produced to give us immunity against diseases. Vaccines can be given by mouth or by injection.
The reason for immunisation is to decrease the chance of children from getting infectious diseases. Moreover, if the majority of people are immunised and obtain the immunity, infectious diseases will not be easily spread in the community. As a result, the health and lives of individuals and the community are protected. REF http://www.fhs.gov.hk/english/health_info/child/14828.html
Myth 1: Better hygiene and sanitation will make diseases disappear – vaccines are not necessary. FALSE Fact 1: The diseases we can vaccinate against will return if we stop vaccination programmes. While better hygiene, hand washing and clean water help protect people from infectious diseases, many infections can spread regardless of how clean we are. If people are not vaccinated, diseases that have become uncommon, such as polio and measles, will quickly reappear.
Myth 2: Vaccines have several damaging and long-term side-effects that are yet unknown. Vaccination can even be fatal. FALSE Fact 2: Vaccines are very safe. Most vaccine reactions are usually minor and temporary, such as a sore arm or mild fever. Serious health events are extremely rare and are carefully monitored and investigated. You are far more likely to be seriously injured by a vaccine-preventable disease than by a vaccine. For example, in the case of polio, the disease can cause paralysis, measles can cause encephalitis and blindness, and some vaccine-preventable diseases can even result in death. While any serious injury or death caused by vaccines is one too many, the benefits of vaccination greatly outweigh the risk, and many more injuries and deaths would occur without vaccines
Myth 4: Vaccine-preventable diseases are almost eradicated in my country, so there is no reason to be vaccinated. FALSE Fact 4: Although vaccine preventable diseases have become uncommon in many countries, the infectious agents that cause them continue to circulate in some parts of the world. In a highly inter-connected world, these agents can cross geographical borders and infect anyone who is not protected. In western Europe, for example, measles outbreaks have occurred in unvaccinated populations in Austria, Belgium, Denmark, France, Germany, Italy, Spain, Switzerland and the United Kingdom since 2005. So two key reasons to get vaccinated are to protect ourselves and to protect those around us. Successful vaccination programmes, like successful societies, depend on the cooperation of every individual to ensure the good of all. We should not rely on people around us to stop the spread of disease; we, too, must do what we can.
Myth 8: It is better to be immunized through disease than through vaccines. FALSE Fact 8: Vaccines interact with the immune system to produce an immune response similar to that produced by the natural infection, but they do not cause the disease or put the immunized person at risk of its potential complications. In contrast, the price paid for getting immunity through natural infection might be mental retardation from Haemophilus influenzae type b (Hib), birth defects from rubella, liver cancer from hepatitis B virus, or death from measles.