Vaccines in practice - 2010


Monitoring and regulation of vaccine safety
Kenneth Barry Walker
pp 1-4
Mass vaccination strategies have been one of the most successful public health interventions, significantly reducing childhood (and adult) morbidity and mortality (see Figure 1 for an example). However, where clinical intervention in the form of mass vaccination is used, and where the target group is healthy young children, it is imperative that the quality and efficacy of the vaccine be above question. There is always a balance to be struck between the minute risk of using a vaccine and the substantial benefit, to both the individual and society, of immunity induced by a vaccine.
Comment: Is the honeymoon over?
Peter M English
pp 3-3
Vaccines in practice recently included an article explaining herd immunity and the honeymoon effect, which occurs when a vaccine is introduced to protect a population against a disease to which a high proportion of the population is already immune. One of the paradoxes of immunisation is that as you vaccinate children against ‘childhood diseases’, the diseases may start to affect older people. As there is so little of the disease around, children who are unvaccinated, or who remain vulnerable despite vaccination, are, unlike pre-vaccination generations, much less likely to catch the disease as children, and may instead catch it as adolescents or adults.
Bacterial conjugate vaccines: an update
Clarissa Oeser and Shamez Ladhani
pp 5-7
Many pathogenic bacteria have a polysaccharide capsule which allows the organism to evade the host immune system. Polysaccharide vaccines using extracted and purified forms of the bacterial outer polysaccharide coat have been shown to prevent invasive infection in older children and adults. The duration of protection, however, is usually limited to three to five years because polysaccharide vaccines activate B-cells through a T-helper cell-independent pathway. This leads to the formation of plasma B-cells and antibodies which are predominantly of the IgM isotype, with little development of memory cells.
Immunisation policy: health inequalities
Vanessa Baugh
pp 8-9
Health inequalities largely result from social inequalities. The UK government recognises that life expectancy is influenced by socioeconomic status and that health service access is inequitable across parts of the country. In response, it has called for a narrowing in the gap between the health status across the various social groups.
Should the UK lower the influenza vaccination age?
Catherine Heffernan
pp 10-11
Epidemics of seasonal influenza typically occur from late autumn to early spring in the UK. While rates of infection are highest in children, rates of serious illness and death are highest in those aged over 65 and in those with underlying medical conditions. The most effective way of reducing morbidity and mortality in those most at risk of complications, and in healthy working adults, is immunisation.