Question

Why is it difficult to develop some vaccines

Answer 1

it is difficult for many of us today to appreciate the dangers of childhood viral infections. In the 1950’s, hundreds of children were crippled by polio, and as recently as the 1970’s, hundreds more died every year in South Africa from measles. Polio and measles are now rare thanks to successful vaccination programmes, and, because the serious consequences of such diseases are no longer familiar, we have ceased to fear them. Thus we can become blasé about the need to vaccinate our children, or dwell on possible vaccine side effects, both real and rumoured. However, the incidence of polio and measles is still significant in neighbouring countries such as Zimbabwe, Angola and Mozambique, where vaccination programmes have broken down through war and social upheaval. These diseases can rapidly re-enter South Africa if they are given the opportunity - and the opportunity they require is simply enough unvaccinated children.