The syllabus states "process, analyse and present information from secondary sources to evaluate the effectiveness of vaccination programs in reventing the spread and occurrence of once common diseases, including smallpox, diphtheria and polio."
I took that to mean to evaluate just one, but I am now thinking that you are correct.
For polio, the disease caused the paralysis of thousands of children who were infected. In the mid 1950s, like 1955, a vaccine was developed which was injected, however in the early 1960s, one was developed which could be taken by mouth. Although outbreaks still occur (due to varying views of immunisation), incidence are far less common. In fact, numbers are down by 80%. The ease of administering the innoculation made it very suitable. Polio is found in six countries in some major hot spots. Although the vaccine is effective, many countries have stopped performing preventive immunisation campaigns.
Six countries in the world were polio-endemic at end-2003, the lowest-ever number. They are Nigeria, India, Pakistan,
Niger, Afghanistan and Egypt.
• In 2004 (as of 13 April 2004), 89 cases have been reported, 63 of which are in Nigeria. Of note is the significant
decrease in cases in India - 8 cases have been reported in 2004, compared to 68 for the same period in 2003.
• Of further note is the absence of polio cases in Egypt in 2004 (last positive environmental sample on 6 January 2004).
• The majority of polio cases globally can be linked to just six states or provinces — Kano (Nigeria), Uttar Pradesh and
Bihar (India), North West Frontier Province, Sindh and Punjab (Pakistan).
• The goal of the Global Polio Eradication Initiative, spearheaded by national governments, the World Health
Organization, Rotary International, the US Centers for Disease Control and Prevention and UNICEF, is to interrupt
transmission of wild poliovirus by end-2004 leading to global certification by 2008.
However, diptheria is a bacterial infection. According to the WHO "it was a cyclical epidemic disease but, with rising immunisation levels in all countries, epidemics gave way to sporadic cases and intermittent outbreaks of low intensity. This change occurred in the 1940s and 1950s in most industrialized countries, coinciding with an increased use of DTP. No longer was diphtheria thought of as a child killer. Tropical countries are more likely to experience cases of skin infection than the outbreaks of diphtheria which, in cooler climates, tend to be nasopharyngeal infection.
"Recent large epidemics of diphtheria in several countries of Eastern Europe again called attention to this disease. They highlighted the need for the following five major activities in diphtheria control: adequate surveillance; high levels of routine immunization in appropriate age groups; prompt recognition, appropriate case management and the availability of adequate supplies of antibiotics and antitoxin; rapid case investigation and management of close contacts; outbreak management.
They continue in saying "The priority for every country is to reach at least 90% coverage with three primary doses of DTP as early as possible in the schedule. DTP is the core vaccine in childhood immunization services. Since 1990 the global coverage for this triple vaccine has only been around 80%.
Where resources permit, additional doses of DTP should be given after completion of the primary doses. However, the need and timing for such additional booster doses should be addressed by individual national programmes.
In countries where pertussis is no longer a public health problem, bivalent vaccine in its paediatric form (DT) may be used for booster doses in preschool children. The adult form (Td) should be used for booster doses in children aged seven years and over and in adolescents and adults. The following three DTP immunization schedules are in widespread use:
"Three doses: three primary doses of DTP vaccine given during the first year of life; four doses: primary series of three doses reinforced with a booster dose usually administered around the second or third year of life; five doses: primary series of three doses reinforced with a first booster dose in the second year of life and a second booster given before entering school at the age of four to six years."
In all these instances, a public health campaign was initiated by a global health organisation (WHO). They have reduced the incidence of once common diseases dramatically and instead they are just sporadic and usually isolated cases. Although side effects result from immunisation, this can be expected, but overall, vaccination programs are effective based on the above criteria.
