Vaccines are considered one of the greatest achievements of biomedical science and public health, and immunization probably is the most cost effective intervention against infectious diseases to date. Despite recent public concerns about safety, immunization is much safer than accepting the risks for the diseases these vaccines prevent.

The World Health Organization introduced its Expanded Programme on Immunization (EPI)
in 1974 to strengthen effective vaccine delivery and to decrease mortality due to vaccine preventable causes.

The national immunization schedule gives coverage for polio, tuberculosis, diphtheria, pertussis, tetanus, hepatitis B, HiB and measles. The BCG vaccine and polio drops are given birth usually at the hospital and then the follow up out patient vaccines start at 6weeks and continue at various intervals up to the age of 5years.This article will cover vaccines required or recommended for 5year old pre-school children.

What are vaccines made of?
Most vaccines contain purified fragments taken from killed bacteria or viruses. Some vaccines contain live viruses, but these do not cause disease.

How do vaccines work?
Vaccines “teach” the immune system how to recognize and fight bacteria and viruses before an infection occurs.

At 5year immunization the child should be vaccinated with DT and OPV. The DT is an injection for diphtheria and tetanus, and the OPV is oral drops for the prevention of polio. Polio vaccination is also available in an injectable form alone or in combination with other vaccines, such as Tdpolio.

Polio is a highly infectious disease affecting the nervous system. Complications of the disease include deformity and paralysis. Diphtheria is an acute disease caused by a toxin produced by the bacteria. The illness is characterised by inflammation of the upper respiratory tract(throat and larynx). It can result in suffocation, paralysis, heart failure and death. Tetanus toxin also produces an acute often fatal disease. The toxin results in the muscles becoming rigid and going into spasm(lockjaw).

There are several important vaccines that are not included in the EPI SA schedule. These include the influenza, hepatitis A, MMR(measle, mumps and rubella), pneumococcal(for the prevention of meningitis, pneumonia and ear infections) and chicken-pox vaccines. Parents and care-givers should be aware that there are slight variations in immunization schedules between government institutions and private clinics, as well between the different private clinics themselves. It is therefore important that the “road to health card”/immunization card be taken with at every visit.

Measles vaccine is included in the national schedule, but mumps and rubella vaccines are not. Congenital rubella remains an important preventable problem in South Africa. Mumps, specifically in adults, can cause orchitis and infertility whilst meningo-encephalitis and deafness can occur in chilhood. If financially possible it is advisable to substitute the 15-18month measles with the MMR. A booster MMR is then given at 5years. Studies have found that there is NO association between MMR and autism.

It is important to check and up-date your child's immunization card. If you are concerned that your child has missed any vaccines or would like to know more about the other vaccines use this opportunity to consult your health practitioner. Remember the old adage “prevention is better than cure”!