Introduction
The introduction of Hib vaccine into national immunization programs in developing countries has suffered from a long delay following vaccine licensure and availability in developed countries. The delay was attributed to multiple factors, including lack of data on burden of disease or vaccine impact, as well as inadequate supply, cost and financing limitations, and lack of political will [1]. By 2004, only a few developing countries had included Hib vaccines in their national immunization programs, despite various efforts by WHO and GAVI, and despite the high effectiveness of these vaccines and their documented impact. However, between 2005 and 2009, a significant surge in Hib vaccine adoption took place, with the number of GAVI-eligible countries that introduced or were approved to introduce Hib vaccine increasing from 19 of 75 (25%) in 2005, to 66 (92%) of 72 in 2009 [2].
In the early years of GAVI support, and in order to avoid the same delays that were observed with hepatitis B vaccine introduction, an assessment of the obstacles to Hib vaccine introduction led to corrective measures that contributed to accelerating Hib vaccine uptake. First, data from multiple studies, ranging from resource-intensive vaccine probe studies to rapid assessment of burden using the WHO Hib Rapid Assessment Tool (HibRAT) [3], indicated that Hib disease constituted a significant public health problem globally, and led to the revision in November 2006 of the WHO position statement [4]. This revised statement clearly recommending global use of Hib vaccine enabled all GAVI-eligible countries to apply for vaccine introduction without having to provide evidence of local burden, which had been an obstacle for some countries in GAVI phase I. Though data on local burden of disease is desirable, countries were encouraged to use data from neighboring countries, with similar population and socioeconomic characteristics, and global estimates. Second, as part of GAVI's phase II, new co-financing guidelines offered financial commitment until 2015 along with a small country co-payment, which helped alleviate countries’ concerns about ability to sustain the long-term program. Third, additional Hib vaccine formulations became available, including a fully liquid combination vaccine (DTP-HepB-Hib), and new manufacturers entered the market, thus decreasing concerns about limited supply and increasing hopes that the vaccine's price would decline with time. Finally, the advent of the Hib Initiative (HI) in 2005, at a critical time or a “tipping point” when all these favorable conditions came together, helped maximize their impact on Hib vaccine adoption. The HI was a 4-year project, initiated and funded by the GAVI Alliance in 2005, with the main objective of accelerating evidence-based decisions for Hib vaccine introduction in low-income countries. The HI was a consortium of academic and public health and institutions (Johns Hopkins Bloomberg School of Public Health, the London School of Hygiene and Tropical Medicine, the World Health Organization, and the Centers for Disease Control and Prevention). The consortium brought together a set of diverse skills in research and surveillance, communications and advocacy and policy-support, and utilized the global mandate of WHO and its network of regional and country offices to provide direct support to ministries of health. Building on lessons learned from the introduction of other vaccines, principally hepatitis B, the HI developed a strategic plan to address the key barriers for introduction. The plan focused on three areas that were determined critical to overcome the barriers for vaccine introduction—communications and advocacy, research and surveillance, and coordination of programmatic activities such as finance, supply and vaccine logistics. This paper reports on the experience and approach of the HI and the many lessons learned in implementing its strategy, hoping that these lessons will be useful for ongoing efforts to introduce other new vaccines.