Thousands of miles away in Siberia, in a dingy flat in the gypsy neighbourhood, I meet two sisters who are both HIV positive. They contracted the virus through using dirty needles. Both are heroin addicts. On the floor of their apartment are little spots of blood, trace marks of the junkie who struggles to find a vein into which they can inject. The sisters work as prostitutes on the streets of Irkutsk, and they say that scores of their friends are HIV positive. The Russian statistics back them up – the country now has the fastest growing HIV infection rate in Europe.

Down in Bombay, I was taken to a flat in the overcrowded slums. A grandmother lived there with two small children. The children's parents were both dead. The father had contracted HIV from a prostitute and brought it home to his wife. Their five-year-old son was now seriously ill with Aids. The grandmother wouldn't tell the neighbours what was wrong. I should rephrase that: she couldn't tell the neighbours. What would happen if she did, I wondered? They would reject him, she answered, maybe even try to throw the family out.

Before I left Bombay I met a formidable Aids campaigner. Dr Lelita Edwards runs counselling groups for HIV-infected people. "I want to go to the top of a mountain and scream 'wake up'," she told me. The denial, the stigma, the bureaucratic inertia had all become too much for Dr Edwards. After a journey through the hinterland of Aids – from Africa, to Asia, to Russia, and home to London – I have some small idea of what she means.

The scale of this crisis defies comprehension. Translate the millions of deaths into the social, economic and emotional impact on cities, towns and villages across the developing world and you recognise a humanitarian catastrophe unlike anything we have previously seen. And yet the response of the international community is marked by a strange inertia. We act as if Aids were a dark moment of the 1980s and 1990s; it no longer gets headlines or commands vast resources from government funds.

We perceive it as the problem of black and brown people, just another of those miseries that go hand in hand with being a citizen of the Third World. It is like tuberculosis and river blindness and sleeping sickness, the illnesses of dark continents seen through the filter of a latter-day Victorian consciousness. Send out the missionaries and seal up your borders and leave them to their wretched plagues. The wealthy nations celebrate the merits of Viagra, the poor ones bury their children.

The drug companies market anti-retroviral drugs at a cost the countries of the developing world cannot dream of affording, and have been slow to develop cheaper alternatives. But they merely reflect the purchasing power of their client base. The customers of the west – government and individuals – can pay the serious money (£10,000 a year in the UK approximately), and they determine the price. There have been a few cases where drug companies have been effectively shamed into setting aside the profit motive and providing drugs to HIV-positive women. But if these profit-making conglomerates wanted to contribute to humanity they would radically reduce the price of drugs for Aids sufferers in the worst-hit areas, and concentrate their energy on developing much cheaper alternatives.

Drugs will only alleviate the suffering. They won't prevent the tens of thousands of new infections every day in places such as South Africa, Botswana and India. Ask the leaders of any of these countries if they are worried about Aids, and they tell you, "of course, of course". But the lack of energy and honesty about the pandemic is staggering. We have had South Africa's Thabo Mbeki indulging in fantasies about the unproven link between HIV and Aids; in Russia the system is riddled with inefficiency and the central government is crawling when it should be sprinting; while India quibbles with statistics and would like to believe that things are not nearly as bad as the evidence suggests.

The encouraging fact is that local organisations have taken up the fight with alacrity. They are not waiting for a western cavalry charge that may never come. Women such as Dr Edwards in Bombay or Lillian Cingo in South Africa are apostles of honesty in a landscape of evasion. They have looked at Uganda, where President Yoweri Museveni spoke bluntly with his people and sent teams into the countryside to urge the use of condoms. He was willing to challenge dangerous behaviour patterns, and the result was a substantial reduction in the infection rate. Uganda went from being an Aids nightmare to a beacon of hope in Africa.

In both South African and India I have come across social workers who daily make the rounds of sex workers, urging them to insist on their clients' using condoms. It doesn't always work. Poverty leaves many women vulnerable to customers who offer more money for unprotected sex. And in societies where early death from a variety of poverty-based diseases is frequent, it can be difficult to persuade a woman or man that Aids is anything more than just another risk among many. The poverty trap breaks up families. It sends men to the cities in search of work while their families languish in the villages; and it sends young girls to the brothels of the shanty towns.

As Lillian Cingo, who heads one of South Africa's main outreach groups, said: "We are dealing with people who worry whether they will have food to put on the table for their children. Asking them to think about Aids, something that can kill in seven or 10 years' time, can be very difficult." But in many areas there is evidence of women – sex workers and the partners of men who visit brothels – beginning to feel empowered, a small but vital movement in the right direction. The change is incremental, but it does show what honesty and commitment can achieve.

Why should we give a damn? I could give you a lot of reasons, but consider just two: the past two decades have proved that Aids knows no borders. It travels far and fast; if infection rates are rising dramatically in the developing world, there is every likelihood that they will rise here too. This happens because people travel, but also because we now see Aids as something from the past, and therefore requiring less care and concern. It is a fatal misperception.

But the compelling reason is not to do with enlightened self-interest but with the kind of world we want to live in. Aids sufferers of the world – from London to Lesotho – suffer from a physical, not a moral, disease. It can be prevented, and its symptoms greatly alleviated. And if we give enough of a damn and shout long and loud at the corporations and political leaders, it might be possible to save millions of lives.

The writer is a BBC Special Correspondent

© 2000 Independent Digital (UK) Ltd.

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