IN THE modern world, 20 years seems a long time to be at war, but it is hardly surprising when the enemy is as elusive, and pervasive, as HIV—the virus that causes the disease AIDS. It is two decades since scientists first identified the cause of what was a baffling new syndrome ravaging immune systems and destroying lives. Since then, AIDS has gone from being the scourge of relatively small groups, such as homosexuals and intravenous-drug users in rich countries, to arguably the biggest threat to life and prosperity in the developing world.

Although the epidemic continues to tear across Africa, Asia and Latin America, there is much optimism among policymakers and public-health experts that the battle against the disease has reached a turning point. Anti-AIDS programmes are growing larger and more coherent. And there is a growing political commitment to ensure that more money is spent and, crucially, new methods are exploited, in getting AIDS drugs to poor people.

Hope might seem odd in the face of this week’s grim accounting from UNAIDS—the United Nations agency monitoring the disease. In its annual report on the epidemic, it estimates that a shocking 40m people are infected with HIV—2.5m of them are children. In 2003 alone, 5m were newly infected. Although the total number of people living with the virus seems to have grown more slowly in recent years, Peter Piot, head of UNAIDS, cautions against complacency. This apparent levelling off of the figures is largely the result of a steady rise in the AIDS death rate, from just over 2m in 1999 to 3m this year.

Despite such dreadful figures, Stephen Lewis, Kofi Annan’s special envoy for AIDS in Africa, says he is more optimistic than he has been for years. Firstly, political leaders, especially in sub-Saharan Africa, are no longer as silent or apathetic as they were in the 1990s. Many are avidly, and publicly, discussing how to build up their national health-care systems to deal with AIDS. Much of this planning has yet to translate into action, though. And significant issues need to be addressed, such as the stigma that prevents people from getting tested or unfair inheritance laws that leave widows vulnerable. Nevertheless, public acknowledgment of the size of the problem and the need to act are important steps in the right direction.

The second reason for optimism is that there is now more money available. UNAIDS says about $4.7 billion was spent on AIDS in low and middle-income countries this year, compared with just $200m in 1996. The American Congress looks set to approve $2.4 billion to be spent next year, largely in the 14 countries that stand to benefit from the Bush administration’s five-year plan to fight AIDS in Africa and the Caribbean. The multilateral Global Fund to Fight AIDS, Tuberculosis and Malaria, which was founded last year, has already committed $2.1 billion to projects in more than 120 countries.

And yet much more will be needed, both from wealthy donors and the governments of poor countries. Another $4.1 billion is needed by 2005 merely to honour and extend the Global Fund’s commitments for example. UNAIDS says the world needs a total of $10 billion a year by 2005 just to keep AIDS in check.

The biggest change in the past year is a significant boost to the prospect of providing anti-HIV medicines. At the moment, only 800,000 people take the cocktail of drugs needed to keep HIV under control. More than three-fifths of these patients are in rich countries. Most of the rest are in Latin America. Poor people have gone without drugs because they have been too expensive, and the countries where they live lack the staff and medical systems to deliver the appropriate medications.

These factors are now changing. Since 2000, the cost of the drug cocktail needed to treat AIDS has fallen from $10,000 per patient annually to $300. This is largely thanks to competition from generic medicines, produced by firms such as Cipla, a drugmaker in India. Innovative drug firms holding patents on these medicines have also cut their prices for poor countries. Prices will also fall further thanks to a new deal brokered by the Clinton Foundation, a charity established by the eponymous former President Bill. Four Indian drugmakers will produce anti-retroviral medicines for roughly $140 per patient annually—courtesy of production efficiencies worked out between the foundation and the drugmakers.

There have been other moves this year to expand access to drugs. In August, members of the World Trade Organisation (WTO) agreed on compulsory licensing, so that countries without the capacity to make their own drugs could import generic versions from countries whose domestic patent laws might prohibit this. Canada is now planning to change its laws to allow its home-grown companies to supply this market.

This week also saw the launch of Cumvivium, a new charity set up by the International Federation of Catholic Pharmacists with the blessing of the Vatican. The federation aims to help poor countries to obtain two-dozen types of low-cost pharmaceuticals, and hopes to receive funds from the European Union for this. It has signed agreements with over 60 drug firms, and wants to start pilot schemes in two countries early next year.

In addition, the South African and Chinese governments announced this month that they would provide anti-retroviral drugs to everyone who needs them. This is a huge step forward for countries that have spent years downplaying their AIDS crises. South Africa’s programme is particularly bold. Mr Piot calls it “historic”. It will cost about $680m a year by 2007 to buy drugs, set up clinics and train thousands of health workers.

This flurry of activity will receive a further encouragement when, on December 1st, the World Health Organisation (WHO) launches “3 by 5”—a plan to get 3m people on anti-retroviral treatment by the end of 2005. If this is achieved, it will represent a ten-fold increase in the number of people in poor countries taking anti-retrovirals. This will be no easy task, warns Jim Kim, one of the programme's architects.

The WHO also hopes to use its negotiating clout to help poor countries procure good drugs cheaply, and its expertise to create the health-care systems to deliver them. This will involve training volunteers, rather than just qualified medical personnel, to deliver simplified drug regimens and to monitor their effects, in remote parts. Rather than waiting for a complex laboratory assessment before starting treatment, as would happen in richer places, patients will be prescribed drugs straight away. This is controversial, but groups such as Médecins Sans Frontières, a big aid organisation, have shown that it can work. Dr Kim is unapologetic: “If they wait to do things as we do in the West, then it will take too long and there will be many more deaths.”

Money for the initiative may well come largely from the Global Fund. Richard Feachem, its head, reckons the programme will cost roughly $3 billion a year for the next two years. And the WHO is busy forming emergency-response teams to help countries participate in the scheme. Already 20 countries have applied to join. The scheme will require careful monitoring but Dr Kim says it will prolong the lives of millions of people. It will also have the useful side-effect of establishing health-care systems that can deliver long-term therapies. These, in turn, should prove useful in coping with future chronic diseases, such as diabetes. Offering people therapy could also encourage them to seek testing and counselling. As more people find out that they are HIV positive, the stigma surrounding the disease should hopefully diminish.

If the world is, at last, trying to muster an adequate medical response to AIDS in poor places, the same cannot be said about the vast socio-economic implications of the epidemic. It is hard to fathom, let alone fix, a situation in which most teachers and farmers are expected to die of AIDS, as in Botswana.

Arguably the epidemic’s cruellest legacy, though, is the orphans it is leaving behind. Around 11m children in sub-Saharan Africa have lost at least one parent to AIDS. This is 11 times the number in 1990. The situation is about to get a lot worse, according to a report published this week by UNICEF. By 2010, there could be as many as 20m AIDS orphans in sub-Saharan Africa. Even if widespread anti-retroviral treatment takes hold, some think it will, at best, spare only 1.8m children from such a loss.

If not for AIDS, the number of orphans worldwide would have been tumbling. As it is, roughly one in ten sub-Saharan children is now an orphan. A third of these are the result of AIDS. Orphaning rates above 5% worry UNICEF because they exceed the capacity of local communities to care for parentless children. So how do places such as Zambia, where almost 12% of children are AIDS orphans, cope?

Not well enough, says UNICEF. More than half the countries south of the Sahara have no national plans to care for AIDS orphans. Most African orphans are taken in by their extended families which have, in the past, masked the problem by dispersing it. These households, though, are often headed by frail grandparents struggling to cope with these extra dependants.

Arguably the epidemic’s cruellest legacy is the orphans it is leaving behind. Around 11m children in sub-Saharan Africa have lost at least one parent to AIDS

Orphans tend to be poorer than non-orphans, and to face a higher risk of malnutrition, stunting and death—even if they are free of HIV themselves. They also endure the psychological trauma of watching parents waste away, and often have to watch as their subsequent care-givers suffer the same fate. Many are also separated from their siblings. Small wonder that a recent study of more than 350 AIDS orphans in Congo found that nearly 40% were suffering from post-traumatic stress, and a third were depressed, anxious or irritable.

Their future prospects, too, are grim. Orphans are less likely to attend school—partly because they cannot afford the fees but also because step-parents tend to educate their own children first. Many drift on to the streets, as the teeming slums of Nairobi and Lusaka attest. Many go to work. In Zambia, for example, more than two-thirds of the child prostitutes are AIDS orphans. As a result, these children are themselves at high risk of HIV infection.

As Mr Lewis points out, the orphan problem could have dire long-term effects. Today’s AIDS orphans, he says, are having children of their own. As they have never learned parenting skills from their own mothers or fathers, they may find it hard to be parents themselves.

Some church groups and other NGOs are trying to break this awful cycle. In Malawi, for example, Save the Children is supporting a programme that tries to help orphans in their own families. This is better than institutionalising the children, an option that is also more expensive.

In Uganda, another international NGO called Plan is helping families to come to terms with an impending death. This includes training guardians and helping soon-to-be-bereaved children to prepare “memory books” so that they will have a record of their parents.

Some governments have made moves to tackle the orphan crisis. In Uganda and Kenya, free primary-school education is allowing millions more children—including AIDS orphans—to get an education. Uganda has been so successful in curbing its epidemic that the number of AIDS orphans should start to decline by 2010. No other sub-Saharan country can expect such a blessing. One preliminary estimate from Columbia University puts the cost of tackling Africa’s orphan problem at $4 billion annually. But as AIDS spreads elsewhere in the world, so too does the orphan problem, in countries as far afield as Haiti and India.

While there is welcome progress across many fronts in Africa, much more needs to be done. The same is true of other regions where the disease is now taking hold—among them eastern Europe, India and China. Indeed, the lessons learned and mistakes made in Africa should prove useful elsewhere. But it will take years before the impact of these new, large-scale initiatives are felt. AIDS itself is hard enough to beat; its broader social effects defy any quick fix.