BOB ABERNETHY, anchor: One major reason for the spread of H.I.V.-AIDS in the developing world is the fear many people have of getting tested. This is partly because of the stigma associated with H.I.V., and also because there is often little hope of getting treatment.

But there are encouraging developments. Uganda this week became the second African nation to make H.I.V. drugs available to its population free of charge. And routine testing has begun in Botswana, where 40 percent of adults are H.I.V. positive -- the highest infection rate in the world.

Fred de Sam Lazaro went to sub-Saharan Africa, where more than 30 million people are infected.

FRED DE SAM LAZARO: In much of the developing world, an AIDS test -- if one is available -- is a dreaded event. That's because in poor countries where there's no treatment, being H.I.V. positive is tantamount to a death sentence.

Here in Southern Sudan, this woman came in after suffering skin rashes and fever. Sudan has suffered from decades of civil war. Its poverty and displaced populations are a breeding ground for an outbreak of H.I.V.

At one of the few clinics offering care, counselor Grace Kadayi prevailed on her client to be tested -- a tough decision, and, in this case, a tough outcome.

GRACE KADAYI (Counselor): You know that when you are positive, the end is death, so much so that people think about their spiritual life and they prepare intensely, but I feel that it is useful because of that.

DE SAM LAZARO: This client is a typical case: a woman infected by a spouse who had many other sex partners. He's not part of her life any more, she said, but he is part of perhaps the grimmest H.I.V. statistic: worldwide more than 90 percent of those who are positive for the virus don't know it and continue to infect others for years before they finally become ill.

Ambassador RICHARD HOLBROOKE (Global Business Coalition on H.I.V./AIDS): Ignorance only spreads the disease.

DE SAM LAZARO: Former U.S. ambassador to the U.N. Richard Holbrooke says because of its early association with homosexuality in the U.S., AIDS has been stigmatized, particularly in more conservative societies in the developing world. Holbrooke is leading a campaign for expanded testing. He says it's the only way to stop the spread of AIDS.

Amb. HOLBROOKE: In no other health crisis in modern history would testing not have been a massive central factor. As a doctor said to me once, they threw out the whole rule book on epidemics when AIDS hit. And yet AIDS is the worst health crisis in history. That was because of the stigma. That was because of the battle over the way it's spread, and, as a result, a public health crisis was turned into a political issue, and testing became voluntary because they were afraid that confidentiality otherwise would be violated and they would be stigmatized. But it should have always been encouraged testing -- not mandatory, but encouraged testing.

DE SAM LAZARO: But many experts insist voluntary testing can work, especially now that anti-retroviral or ARV drugs are becoming affordable in some developing countries. These life-extending drugs have long been available in rich nations like the U.S.

Holbrooke agrees drugs are important. But he says testing cannot wait for ARV.

Amb. HOLBROOKE: We need access to treatment, Fred, at all times in order to encourage testing. But even if there wasn't full access to treatment, isn't it better to find out who is and -- even more importantly, perhaps -- who isn't infected? And anyway, if you don't know who has the disease, how do you know who to treat?