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A. Keywords
AIDS epidemic, microbe, HIV(human immunodeficiency virus), vaccine.
Vocabulary
epidemic, plague, relentlessly, microbe, lethal, TB, malaria, prevalence, human immunodeficiency virus(HIV), life expectancy, magnitude, pandemic, fester, inconceivable, therapeutic, vaccine, avert, unparalleled, concerted.
Predicting the future is risky business for a scientist. It is safe to say, however, that the global AIDS epidemic will get much worse before it gets any better. Sadly, this modern plague will be with us for several generations, despite major scientifc advances.
As of January 2000, the AIDS epidemic has claimed 15 million lives and left 40 million people living with a viral infection that slowly but relentlessly erodes the immune system.
Accounting for more than 3 million deaths in the past year alone, the AIDS virus has become the deadliest microbe in the world, more lethal than even TB and malaria.
There are 34 developing countries where the prevalence of this infection is 2 precent or greater.
In Africa nearly a dozen countries have a rate higher than 10 percent, including four southern African nations in which a quarter of the people are infected.
And the situation continues to worsen, more than 6 million new infections appeared in 1999.
This is like condemning 16,000 people each day to a slow and miserable death.
Fortunately, the AIDS story has not been all gloom and doom. Less than 2 years after AIDS was recognized, the guilty agent, human immunodeficiency virus, or HIV, was identified.
We now know more about HIV than about any other virus, and 14 AIDS drugs have been developed and licensed in the US and Western Europe.
The epidemic continues to rage, however, in South America, Eastern Europe and sub-Saharan Africa.
By the year 2025, AIDS, will be by far the major killer of young Africans, decreasing life expectancy to as low as 40 years in some countries, and single-handedly erasing the public health gains of the past 50 years.
It is Asia, with its huge population at risk, that will have the biggest impact on the global spread of AIDS.
The magnitude of the pandemic could range from 100 million to 1 billion, depending largely on what happens in India and China.
Four million people have already become HIV-positive in India, and infection is likely to reach several percent in a population of 1 billion.
An explosive AIDS epidemic in the US is unlikely. Instead, HIV infection will continue to fester in about 0.5% of the population.
A cure for AIDS by the year 2025 is not inconceivable. But constrained by economic reality, these therapeutic advances will have only limit benefit outside the US and Western Europe.
A vaccine is our only real hope to avert disaster unparalleled in medical history.
A large, concerted effort of research was launched three years ago in the US and hints of promising strategies are emerging from experiments in moneys.
But even if an AIDS vaccine is developed before 2025, it will require an extraordinary effort of political will among our leaders to get to the people who need it most.
