Education has been a key weapon in Uganda's battle
against Aids

In a clearing on a remote hillside surrounded by banana trees, Paulina Namayanja showed me the graves of her children. She said their names aloud, as if repeating a prayer - "Here is Bbale, here is Augustin, here is Kayondo, here is Kate Namasinga…"

Paulina carried on until she had listed seven daughters and sons. All were taken by Aids. Uganda has many mothers who share her sorrow.

Now close to 70, Paulina is struggling to raise the children of her children - 13 in all. They lined up to meet us, with shy smiles and bare feet, giggling at our white skin. When we asked the children how they played, they made a skipping rope from banana leaves.

Paulina is raising them with love, but without toys or books or even enough to eat. Aids has taken away a generation in Uganda. More than one million children have been orphaned by the disease.

It was in the early 1980s around the shores of Lake Victoria in southern Uganda that the Aids epidemic first began.

In a missionary hospital there I asked an Irish nun how many she had seen die of the virus since then. Sister Ursula Sharp found it difficult to answer. "Oh, Lord," she said, "I'd need a big calculator to work that out."

In a clinic not far away I asked an Aids counsellor the same question. Without hesitation she replied: "Two hundred from my extended family, and more than 400 others that I knew."

They tell you in Uganda that every family in this nation of 21 million has been affected. Soon enough, you see that it's true.

The landscape here has been scarred by Aids. There are many empty fields - there is no-one left to plant them. In many places the land holds graves instead of crops. And the roadsides in the trading areas are lined with run-down wooden huts bearing the word 'Clinic.'

For almost 20 years Uganda has seen death on a massive scale, and many more will die in the years to come. But its campaign against HIV has had major results.

One Aids campaigner told me that Uganda had been fighting while three-quarters of Africa had been asleep. "As a woman living with HIV," she said, "I am lucky to live here."

Half a continent away, Senegal has used many of the same tactics to fight a different battle. Unlike Uganda, it did not have to confront an epidemic. In Senegal, the virus has been contained, as if under lock and key.

Here the Aids strategy is a jigsaw of different elements - it had to be. The capital, Dakar, has a modern face but Senegal is a place of subtlety and contradictions. In her cramped office in the Polyclinic in Dakar, Katy Cisse Wone, sociologist and Aids campaigner, told me about her nation. "We surf the internet," she said, "but we still go to the witchdoctor when we have a problem."

Senegal's solution has been to get every part of society involved in the campaign. Sex workers are licensed and tested for HIV here - and even the imams in this Muslim country are part of the fight. They preach fidelity and abstinence but they allow Aids campaigners to promote condoms.

"We call it a chausette, or sock," El Hadj N'Diaye told me. This Senegalese singer had come racing to meet us, his guitar slung across his back.

His song about the risk of Aids has become an anthem in Senegal. In the song he tells his countrymen to "wear a sock." As he sang it for us on a dusty backstreet in Dakar, people walking by echoed the refrain.

With an HIV infection rate that is still below 2%, Senegal has become a poster nation for Aids prevention. But some are worried by this success.

During his early days as a young doctor Mustafa Gueye was powerless to save patients with Aids. Since then he has devoted his life to prevention. Now he is concerned that Senegal is getting complacent. "This country still has the potential to explode," he told us.

Other Aids campaigners told us the same thing. Soukaye Dieng Diop has been part of the fight since she held a young girl, dying of Aids, who begged for help.

"When we go to the factories these days to talk to the workers," she said, "the biggest problem is to convince people they are at risk. They tell me they don't know anyone with the virus and they have never seen anyone with Aids."