Thursday, November 4, 2010

Introducing new vaccines into poor African nations

The GAVI alliance (used to be called the Global Alliance for Vaccines and Immunizations) was founded in 2000 in order to help vaccinate children in poor nations. GAVI funds vaccines in any nation with a GNI per capita of less than $1,000. Glatman-Freedman et al. (published November 2010) investigated the factors involved in successful introduction of the Hib (Haemophilus influenza) and HepB (Hepatitis B) vaccines into poor nations.

The Hib and HepB vaccines are expensive. The basic battery of vaccines (Polio, Diphtheria, Pertussis, Tetanus, Measles and BCG) costs about $1 per child, but the Hib and HepB vaccines raise the cost to $7-13. Taking the new vaccines cost into account, it is very important to determine the best way to introduce them into poor nations.

The authors included in the study GAVI-eligible nations from the WHO African region (AFRO) with population bigger than half a million (35 countries overall).

The countries were included in one of three groups:

I. Countries where both Hib and HepB were introduced.
II. Countries where only HepB was introduced.
III. Countries where neither vaccine was introduced.

(Table and explanation from the original paper)

The authors looked at country-level governance indicators (political stability, government effectiveness, regulatory quality, rule of law, control of corruption and voice and accountability) and (as expected) found that mean scores for all indicators were highest at group I and lowest at group III.

Next, the authors tried to create a combined governance scoring, which consisted of the average of all the governance indicators of each country for each year. There was a significant difference.

Symbols represent means and error bars represent standard error of the mean. Grey plot background highlights the Pre-GAVI years, white plot background highlights the GAVI funding years. * p value smaller than 0.05, ** p value smaller than 0.01 (figure and explanation from the original paper).

Overall, the study indicated that the best way to predict poor African nations ability to introduce new vaccines is to determine their country-level governance. Good governance and political stability help nations attract both foreign aid and investments. Other than funding, the introduction of new vaccines requires trained personnel, cold chain capacity, the ability to reach remote locations, and safe disposal of needles and syringes. Hopefully, this study will be able to help GAVI to introduce new vaccines into poor nations more efficiently.

Glatman-Freedman, A., Cohen, M., Nichols, K., Porges, R., Saludes, I., Steffens, K., Rodwin, V., & Britt, D. (2010). Factors Affecting the Introduction of New Vaccines to Poor Nations: A Comparative Study of the Haemophilus influenzae Type B and Hepatitis B Vaccines PLoS ONE, 5 (11) DOI: 10.1371/journal.pone.0013802

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