Consideration of intersectoral costs and benefits in health economic evaluations of pneumococcal conjugate vaccines: a systematic review.

Immunization is an important investment to reduce the health and economic burden of infectious diseases worldwide (). Over the past decades, many countries have markedly invested in immunization programs (;). However, the introduction of new vaccines has remained a global concern, given budget constraints and competing investments inside and outside the healthcare sector (). Accordingly, health economic evaluations (EEs) are used to inform decision-making about which investment to fund or reimburse in comparison with the best alternative in terms of costs and benefits (). The impact of a vaccine (e.g., conjugate vaccine) is captured by including the benefits and externalities not only related to the treated patients but also to society. The latter, for instance, includes impacts in sectors outside the healthcare sector such as productivity gain, school attainment, and herd immunity (). These are generally referred to as societal, multisectoral, intersectoral (), or spillover impacts (;;) or intersectoral costs and benefits (ICBs) (). This systematic review will use the term ICBs when referring to these impacts of vaccines. Pneumococcal diseases (PDs) are infections caused by Globally, these diseases are associated with substantial health and economic burden, particularly in young children and the elderly in developing countries (;). The World Health Organization (WHO) reported that approximately one million children die of PDs annually (). PDs can yield a wide range of costs in sectors outside the healthcare sector, such as education and the labor market (e.g., productivity) (). In 2000, the 7-valent pneumococcal conjugate vaccine (PCV7) came to the market to prevent PDs in children and was first introduced in the United States. Higher-valent PCVs were licensed (e.g., 13-valent PCV) to cover additional nonvaccine serotypes and are currently available for all age groups (;). Given their wide range of impacts, the prevention of PDs (e.g., conjugate vaccine implementation) can have far-reaching economic implications and may have value to decision-makers beyond the healthcare sector. Therefore, EEs of new preventative interventions, such as PCVs, require an appropriate analysis perspective () for measuring the broader economic impacts of vaccines (). Some initiatives, such as the “Impact Inventory” framework, have been developed to guide researchers and address the full range of sector-specific consequences, including those outside the formal health care sector (). Existing EE studies of PCVs, however, have traditionally focused on a narrow perspective (e.g., a healthcare perspective, only including costs and/or benefits in the healthcare sector) rather than on a broader perspective (e.g., societal, including all relevant costs and benefits with and beyond the healthcare sector). Consequently, these EEs potentially underestimate the total impact of PCVs ().