In the fall of 1994, nearly a million people died in the Rwandan genocide when Hutu extremists massacred minority Tutsis. Those on both sides who survived the killings faced a second threat: a scourge of infectious diseases, including AIDS, tuberculosis, malaria and waterborne illness — less than 5 percent of the population had access to clean water.

Almost 20 years later, striking achievements in health care and health outcomes in Rwanda have set the country apart and made it a model for other poor African countries. Since the genocide, life expectancy in Rwanda has nearly doubled, from 28 years to 56. The country's gross domestic product has tripled in the last decade and more than a million Rwandans escaped poverty between 2005 and 2010 alone.

Paul Farmer, a medical anthropologist, physician and thought leader in the global health sphere, says Rwanda is the only country in sub-Saharan Africa that could meet a majority of the Millennial Development Goals in 2015 -- eight measurable objectives related to poverty, health and education crafted by the United Nations in 2000.

Rwanda's health achievements, specifically the country's drastic declines in maternal and childhood mortality, are the result of focused, intentional and "almost ruthless attention" to improving the delivery of live-saving interventions, says Dr. Gavin Yamey with the Global Heath Group at the University of California, San Francisco.

Accountability is the buzzword . Yamey says Rwanda's minister of health, Dr. Agnes Binagwaho, has demanded that a doctor or nurse phone and inform her any time a mother dies in Rwanda -- day or night.

"Some years ago she was getting eight or nine phone calls a day, and now she's getting one a day," Yamey says.

Rwanda received about $277 million in global aid in 2010 alone. But it was prudent spending that allowed the country to emerge as a health leader, Farmer said in a report published in the British Medical Journal.

Rwanda established universal health coverage through a program known as "Mutuelles de Santé," which required subscribers to pay 10 percent co-payments and yearly premiums. More than 90 percent of Rwandans enrolled in public health care and another 7 percent received coverage through the civil service, military or private insurers. Many preventive interventions like bednets and vaccinations -- as well as treatments for HIV, tuberculosis and certain cancers -- are fully covered.

In addition, Rwanda expanded its AIDS outreach to include rural regions where most Rwandans live, said Farmer. In doing so, Rwanda has maintained an HIV prevalence of only 3 percent for the last seven years. The outcome of these efforts signals hope for other poor countries.

But presidents and finance ministers need something more tangible than hope. The Global Health 2035 report, published by the Lancet Commission, a group of global health experts and economists, offers evidence.

Yamey is a member of the commission and lead author of the report, which is being officially unveiled Tuesday in San Francisco.

"We argue that there is good evidence that the health needs of the most vulnerable people can be most directly and most expediently addressed by investing within the health sector," Yamey says.

Sir Richard Feachem, director of the Global Health Group at the University of California, San Francisco, says the report gives reason to believe in better health outcomes throughout the developing world.

"With respect to the diseases of poverty, the people of the low-income and middle-income countries can have a health status similar to the people in the high-income countries in the next 20 years," Feachem says.

This concept of raising poorer countries' health outcomes to meet those of industrialized nations is known to the commission as the "grand convergence." The idea that focusing on health could benefit both the lives and the economic prosperity of poorer countries was borne out in an earlier report, now 20 years old.

Larry Summers, former chief economist of the World Bank, and Dean Jamison, an economist and professor at the University of Washington -- both are co-chairmen of the Lancet Commission -- wrote the seminal "World Development Report" in 1993. It's the document philanthropist Bill Gates credits with inspiring his interest in global health.

Dr. Matthew Dacso, director of the Center for Global Health Education at the University of Texas Medical Branch at Galveston, read the World Development Report in graduate school.

"It said if you invest in a health system to try to prevent disease and to keep people healthy, they'll be more productive as a population," Dacso says. "Life expectancy will go up and kids won't die under the age of 1." In the early '90s, this was a profound statement, Dacso says, but "now it's just something that we accept."

While Rwanda is certainly a model in sub-Saharan Africa, it hasn't yet achieved the grand convergence.

"Rwanda, while it's still made enormous progress, would still be well short of the kinds of standards that the United States had reached a generation ago," Summers says.

On the other hand, China, Chile, Cuba and Costa Rica -- collectively known as the 4Cs -- have converged and conformed to industrial living standards.

"All had historically high levels of mortality from infections, and maternal and child death, and all managed to reduce those levels of mortality, despite some of these countries facing a number of ongoing kind of systems challenge," Yamey says.

A generation after the '93 report, the 4C countries have eclipsed other low-income countries in health achievements.

"Obviously the countries are different, but what they share in common is an adequately resourced commitment to health," Summers says.

"They all take health seriously," Feachem adds. "The governments of those countries invest substantial sums in public health programs and preventative health programs. It's an important part of public policy."

Cuba, China, Chile and Costa Rica have invested 5 to 11 percent of their GDPs in health care. Costa Rica invests the most at 10.9 percent and China invests the least at 5.2 percent, according to World Health Organization data from 2011.

Summers says the countries also focused on measuring outcomes and committing resources to "places where you're getting the highest bang for the buck," such as childhood death and infectious diseases.

One of the key measures of health outcomes is the under-5 mortality rate, or the number of children out of 1,000 live births that live until they reach 5 years old. For reference, in Gabon, 62 children die each year before the age of 5, and the figure is slightly higher at 68 in Ethiopia, Yamey says.

Before its grand convergence, 61 children died in China for every 1,000 children that were born (the figures do not include stillbirths). Today, China has reduced its under-5 childhood mortality rate to 14 -- a rate roughly equal to those in the United Kingdom and the U.S. in the 1980s.

If a country like China or even Rwanda can improve health outcomes in a generation, why not Gabon? Why not Ethiopia? Low-income countries who focus on increasing access to the most effective treatments -- such as anti-retroviral medications for HIV -- or strengthen their prevention efforts -- by, for example, providing bednets to keep malaria in check -- can improve health outcomes, Yamey says.

"Countries that have aggressively scaled up these tools saw declines in their child-maternal mortality," Yamey says.

Such transformations are a result not only of health investments, but investments in education and sanitation as well. This point was demonstrated by a World Health Report in 1990.

"We know, for example, that female education is a very powerful way to improve female health," Yamey says, noting that educated women are more likely to seek out health services.

"They are also more likely to learn and practice healthy behaviors around water and sanitation," he says.

In addition to rapidly rising incomes, increased rates of female literacy and education also had a huge impact in China.

"If you go back more than 20 years, go back say 50 years, the status of women in China is completely transformed," Feachem says.

However, the health community could have its greatest impact on health outcomes by focusing more specifically on improving the systems for delivering health tools, rather than becoming water and sanitation experts, Yamey says.

Feachem also says it's hard to think of certain countries as models for others.

"It's not a question of copying because each country is different. It's a question of learning and designing a package of investments and interventions that suit your particular country," he says.

In addition to customizing an approach for each low- and middle-income country, these projects must have adequate financial support. The incremental cost of achieving convergence for low-income countries is an average of about $25 billion per year and an average of about $45 billion per year for lower middle-income countries, Yamey says.

Still, the commission forecasts strong economic growth in lower- and middle-income countries and claims that the majority of financing can come from domestic sources.

"Taken together, that $70 billion is roughly 1 percent of the expected GDP growth from 2015 to 2035 across the lower- and lower middle-income countries," Yamey says.

But shifting the focus in developing countries from the urban elite to the poor will not be easy, Summers says. There will still be some countries that need external aid.

"I think that the largest contribution that the global health community can make is through global public goods," Summers says. "When you discover medicines that can contain AIDS, then AIDS is contained and it can be contained everywhere. When you find better approaches to bednets that can combat malaria, those work in many, many different places."