Beyond Complacency

The diversity of HIV's spread worldwide is striking. But in many regions of the world, the HIV/AIDS epidemic is still in its early stages. While 16 sub-Saharan African countries reported overall adult HIV prevalence of more than 10% by the end of 1999, there remained 119 countries of the world where adult HIV prevalence was less than 1%.

Low national prevalence rates can, however, be very misleading. They often disguise serious epidemics that are initially concentrated in certain localities or among specific population groups and that threaten to spill over into the wider population.

Nationwide prevalence in Myanmar, for instance, has been put at 2%. Yet, national HIV rates as high as 60% are being registered among injecting drug users and almost 40% among sex workers. Moreover, in vast, populous countries such as China, India and Indonesia (where individual provinces or states often have more inhabitants than most countries), national prevalence all but loses meaning. The Indian states of Maharashtra, Andhra Pradesh and Tamil Nadu (each with at least 55 million inhabitants), have registered HIV prevalence rates of over 2% among pregnant women in one or two sentinel sites and over 10% among sexually transmitted infection patients -- rates far higher than the national average of less than 1%. In the absence of vigorous prevention efforts, there is considerable scope for further HIV spread. Even HIV prevalence rates as low as 1% or 2% across Asia and the Pacific (which is home to about 60% of the world's population) would cause the number of people living with HIV/AIDS to soar.

All countries have, at some point in their epidemic histories, been low-prevalence countries. HIV prevalence among pregnant women attending antenatal clinics in South Africa was less than 1% in 1990 (almost a decade after the first HIV diagnosis there in 1982). Yet, a decade later, the country was experiencing one of the fastest growing epidemics in the world, with prevalence among pregnant women at 24.5% by the end of 2000.

Low-prevalence settings present special challenges. At the same time, they offer opportunities for averting large numbers of future infections. Today, we are seeing rapidly emerging epidemics in several countries that had previously recorded relatively low rates of HIV infection -- proof that the epidemic can emerge quickly and unexpectedly, and that no society is immune. In Indonesia, where recorded infection rates were negligible until very recently (even among some high-risk groups), there is new evidence of striking increases in the infection rates of HIV. Prevalence has risen significantly among female sex workers in three cities at opposite ends of the Indonesian archipelago, with similar increases also evident at other sites. Among women working in massage parlours in the capital, Jakarta, HIV prevalence was measured at 18% in 2000. Blood donor data now show a tenfold rise in HIV prevalence since 1998 (see Figure 1). Elsewhere, longer-standing epidemics could be on the verge of spreading more rapidly and widely. Nepal and Viet Nam, for example, have registered marked increases in HIV infection in recent years, while in China -- home to a fifth of the world's people -- the virus seems to be moving into new groups of the population.

In other areas of the world, too, time is fast running out if much larger AIDS epidemics are to be averted. For instance, in the Russian Federation, only 523 HIV infections had been diagnosed by 1991. A decade later, that number had climbed to more than 129,000. In a country where injecting drug use among young people is rife (and there are high levels of sexually transmitted infections in the wider population), there is an urgent need for action to avoid an even larger number of new infections.

Prompt, Focused Prevention

Countries that still have low levels of HIV infection should avert the epidemic's potential spread, rather than take comfort from current infection rates. The key to success in low-prevalence settings where HIV is not yet a risk to the wider population is to enable the most vulnerable groups to adopt safer sexual and drug-injecting behaviour, interrupt the virus's spread among and between those groups, and buy time to bolster the wider population's ability to protect itself against the virus.

This means, first, determining which population groups are at highest risk of infection and, second, mustering the political will to safeguard them against the epidemic. At the same time, it is vital to defuse the stigma and blame so often attached to vulnerable groups and to deepen the wider public's knowledge and understanding of the epidemic.

Young people are a priority on this front. Twenty years into the epidemic, millions of young people know little, if anything, about HIV/AIDS. According to UNICEF, over 50% of young people (aged 15-24) in more than a dozen countries, including Bolivia, Botswana, Côte d'Ivoire, the Dominican Republic, Ukraine, Uzbekistan and Viet Nam, have never heard of AIDS or harbour serious misconceptions about how HIV is transmitted. Providing young people with candid information and life skills is a prerequisite for success in any AIDS response.