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Health system cost of delivering routine vaccination in low- and lower-middle income countries: what is needed over the next decade?

On the eve of the 40th anniversary of launching of the Expanded Programme on Immunization (EPI) in 1974, during the twenty-seventh World Health Assembly (WHA), fundamental questions about the level of financing needed to sustain achievements and scale up the EPI in low- and lower-middle income countries continue to permeate the discourse on the economics of immunization. The answer to this question is all the more important in light of the fact that at the sixty-fifth WHA in 2012, ministers of health embraced the Global Vaccine Action Plan (GVAP) – a 10-year global strategic plan for immunization.1 But how much – and in what areas – are the investments needed for this decade? 
 
Today, improved transparency in pricing information allows for relatively accurate vaccine cost estimates.2 Unfortunately, trends in the health system costs of delivering vaccination beyond the cost of the vaccines themselves continue to be poorly understood. During the EPI’s first three decades of existence, they were fairly homogenous. The six basic antigens1 included in the EPI were inexpensive and health system inputs, such as the human resources for vaccination and the vaccine supply chain and logistics infrastructure, accounted for the largest share of total costs in country programmes.3 It was common knowledge that EPI vaccines represented 20% of overall investment in national immunization programmes in low- and lower-middle income countries.4 
 
With the turn of the millennium came a paradigm shift away from this earlier established trend as countries began introducing new vaccines, such as the pentavalent vaccine, a five–in-one combination of the antigens against diphtheria, tetanus and pertussis with those against hepatitis B (HepB) and Haemophilus influenzae type b (Hib).2 During the period from 2000 to 2010, countries rapidly scaled up the use of pentavalent vaccine and, as a result, the total cost of country immunization programmes doubled or tripled.5 Recurrent investments in vaccines suddenly comprised the bulk of immunization programme costs: an average of more than 50% of total investments, and in many cases, well over this average.6 Part of the reason for this rise in the component of the total costs comprised by vaccines was that the incremental health system (i.e. non-vaccine) costs of introducing the pentavalent vaccine were marginal, since this product, despite adding two new antigens – HepB and Hib – to EPI schedules, required no more injections than the previously administered trivalent diphtheria–pertussis–tetanus (DPT) vaccine. In addition, pentavalent vaccines required little additional storage space in the vaccine cold chain.7 
 
Looking ahead, the current decade will see the accelerated introduction into national EPI programmes of additional new, expensive, but highly effective vaccines, such as pneumococcal conjugate vaccine and the vaccines against rotavirus and human papilloma virus (HPV).3 These products are bulkier than the pentavalent vaccine and will require more cold chain storage space and more injections. The health system costs associated with delivering these newer vaccines are likely to outweigh the costs of the vaccines themselves – which reverses the trend in relative importance of vaccine to non-vaccine costs once again.