Jerome Delay, Associated Press
Malagasy children play basketball on what used to be a tennis court in Antohobe, Madagascar, Tuesday, Oct. 23, 2007. Madagascar is waging Africa's most aggressive and comprehensive prevention, testing and awareness campaign and funding it largely with money from the Global Fund to fight Aids, Tuberculosis and Malaria and the U.S. President's Emergency Plan for Aids Relief.

One of the leading impediments to freedom and prosperity in Africa has been disease, particularly HIV, tuberculosis and malaria.

A study in 2007 by the Institute for Democracy in South Africa found that many of the most politically active people on the continent were succumbing to AIDS, in particular. In South Africa alone, 1,000 people were dying each day from AIDS-related diseases.

The problem persists in many regions. Tanzania, for instance, the United Nations reports that, as of 2011, 1.3 million children were orphaned because of disease.

It is difficult for democratic ideals and free-market reforms to take hold amid such problems. Of greater concern is the way such disruptions can lead to social unrest and the rise of radicalism.

The good news is that the world now has this and other diseases on the run. Some important factors have combined to make this so. Drugs, particularly antiretrovirals, are becoming more effective, especially against the retransmission of HIV. The behaviors of people in Africa are beginning to change, meaning fewer people are engaging in actions that would expose them to disease. And, perhaps most important of all, the cost of the drugs, as well as the other items needed for treatments, have dropped to unanticipated low levels — in some cases by as much as 99 percent.

It's time to keep the pressure on. In a few weeks, the U.S. Global Fund to Fight AIDS, Tuberculosis and Malaria will meet in Washington to talk about future funding. The United States has been setting aside about $1.65 billion yearly as its share of this fund. It is critical that it continue to do so for at least the next three years, which would spur other nations to contribute, as well.

Results, a group that lobbies on behalf of the world's poorest people, estimates that, for the first time ever, the world can see a possible end to these diseases. Deaths from tuberculosis have declined by 40 percent due to better treatments made possible by the fund.

Malaria also is on the run. Only 13 years ago, 3 percent of homes in Africa had mosquito nets to protect against the spread of this disease, despite these nets being inexpensive and easy to use. Today, 53 percent have such nets. In addition, effective treatments for those who have contracted malaria have combined to result in a drop of one-third in deaths from the disease.

Add together the behavioral changes, drug treatments for AIDS, the treatments for tuberculosis and the simple mosquito nets and drugs to fight malaria and Results estimates Africa is preserving more than 100,000 lives each month that otherwise would have been lost.

Much the same can be said about efforts to immunize people against polio and measles, two killer diseases largely eradicated in the United States but still problems in developing nations. Since the World Health Assembly decided to focus on polio in 1988, yearly cases have dropped from 350,000 to 187 in 2012. Measles remains a killer worldwide, but if vaccination efforts stopped, the World Health Organization estimates another 2.7 million people would die.

Political turmoil, poor education and improper sanitation practices have long been impediments to the fight against diseases in Africa. Some of these problems remain, but the progress against disease in recent years has been remarkable and must be continued.

Diseases won't wait for nations to find optimum opportunities to pay for treatment. These diseases could return with a vengeance if the fight isn't continued. Without proper supervision of dosages and treatment, resistant strains could develop and spread quickly. Much more needs to be done to educate people and change behaviors, especially in pockets of the continent where prostitution is particularly prevalent.

Americans should remember that extreme poverty and its attendant problems seldom are isolated and contained, no matter how far from home they exist. By eradicating diseases and helping to educate people, the United States can build goodwill and influence the spread of liberty and the development of new trading partners.

That's a huge payback for a relatively small investment.