Boosting vaccination programs for children in 72 poor and middle income countries would save the lives of 6.4 million children in 10 years, and save over $151 billion in treatment and lost productivity, two studies said Thursday. Such immunization efforts and associated benefits will not likely be seen without fuding strategies for poorer countries, involving international donors and commmitments from developed countries, according to a third study. The two studies published Thursday in the June issue of Health Affairs journal examined the impact if vaccines were extended to 90 percent of children in 72 countries, including vaccines to protect against pneumococcal pneumonia, diphtheria, whooping cough, tetanus and measles. \"These findings show the importance of measuring the economic benefits of immunization beyond treatment savings,\" said Meghan Stack, who lead the first study, at the Johns Hopkins Bloomberg School of Public Health, in Baltimore, Maryland. \"Policymakers at both the national and international levels can use these results to get a more complete picture of returns on investment,\" she and colleagues said in a statement. \"By averting lost productivity of the workforce due to avoidance of premature death, $145 billion in long-term economic gains would be achieved,\" said their study. In addition $6.2 billion could be saved in treatment costs as some 426 million cases of illness could be avoided. Diseases that can be prevented with vaccines kill some 2.4 million children each year, according to the World Health Organization (WHO). The second study, from researcher Sachiko Ozawa and colleagues also at the John Hopkins school, meanwhile found that the 6.4 million lives saved through scaled-up vaccine development translated \"into an economic value of $231 billion.\" Using this analysis, called \"value of statistical lives saved,\" the researchers arrived at \"an economic value of life by asking people how much they would be willing to pay in order to avoid a particular risk of death.\" The study found that a global investment \"gives the world\'s poor a health benefit for which they would have paid $231 billion,\" figures that researchers said should inform policy decisions. The third study from GAVI Alliance, with the Results for Developmental Institute, notes that the \"poor countries will be hard-pressed to pay for expanded vaccine delivery without substantial outside support.\" In 2010, the Bill and Melinda Gates Foundation pledged $10 billion over the decade to expand childhood immunization in developing countries, and urged other donor agencies to join the initiative. \"Without major assistance from international donors, the poorest countries will be hard-pressed to pay the costs to reach all of their children with life-saving vaccines,\" said study author Helen Saxenian. Researchers found that low-income countries could pay a small share of vaccine costs -- $0.20 per dose -- and intermediate-income countries could start with $0.20-a-dose charge and increase their payments each year.