New research says 6.4 million lives could be saved in the next 10 years by boosting childhood vaccination rates in the poorest countries.

The three studies, published Thursday, said this would also save $6.2 billion in treatment costs and a further $145 billion in long-term productivity gains.

The studies, published in Thursday's Health Affairs, examined the potential impact if at least 90 percent of children in 72 of the world's most impoverished nations were vaccinated against preventable diseases like whooping cough, tetanus, measles, and pneumococcal pneumonia.

One researcher, Meghan Stack, says the findings give a better sense of the economic benefits of investing in vaccine programs. Another researcher, Helen Saxenian, says major assistance from international donors would likely be necessary to help the poorest nations reach all of their children with life-saving vaccines.

These vaccinations are routinely given in developed countries, but are often too expensive for developing nations.

Several major drug companies this week pledged to cut their prices for some vaccines delivered through the donor-funded Global Alliance for Vaccines and Immunization, or GAVI.

The United Nations estimates that 8 million children around the world die before their fifth birthday. About 1.7 million of them die from vaccine preventable diseases.