How can spam e-mail help fight HIV?

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In 2006, as many as 3.5 million people died from acquired immune deficiency syndrome (AIDS), bringing the total of deaths from this disease since 1981 to more than 25 million [source:].

Human immunodeficiency virus (HIV), the virus that causes AIDS, attacks healthy immune cells and uses them to duplicate itself. AIDS, the final stage of HIV infection, can weaken a person's immune system so much, he could die from a cold.

But there's hope for wiping out this disease, and it may be sitting in your e-mail inbox right now. Efforts to wipe out unwanted spam e-mails could provide the key to ending the AIDS epidemic. Researchers at computer software giant Microsoft are in clinical trials testing the same technology used to create spam-blocking programs against HIV.

Spammers -- people and companies who create junk e-mails -- have found that traditional spam-blocking software works off a list of flagged words. When spam blockers identify these words, they reroute affected e-mail from your inbox to your spam folder.

To get around this, spammers can simply spell words in a way that humans can recognize, but which computers don't. For example, if a spammer uses the word "pharmaceuticals," the e-mail will be blocked. But the spammer can spell "pharmaceutical" as "ph@rm@ceut1cal" to circumvent the spam filter.

Score one for the spammers.

Antispam developers realized that to combat this they would have to calculate all of the possible ways that every single word could be spelled using combinations of letters, symbols and numbers. With all of the different possible combinations for each, this adds up to a lot of work. But Microsoft researchers came up with a breakthrough.

The team developed an algorithm -- a mathematical formula -- that reduces the time it takes to come up with every possible combination for a set of words from one year down to a day. With this algorithm, the researchers are not only able to develop a top-notch spamware product, they have now set their sights on using that same algorithm to ridding the world of HIV.

David Heckerman, one of the Microsoft team's leaders, is not only a computer scientist, he's also a physician. He realized that the same theory used to block spam could also be used to kill HIV. After all, spam and HIV work in similar ways. When HIV attacks an immune cell, it creates thousands of replicas of itself. These aren't exact replicas, though. Each one is a slight variation on the original, and each of these goes on to attack more and more cells, each time replicating into mutated versions of the virus.

This makes it difficult to design a vaccine to kill HIV. To create a vaccine, scientists include antibodies that look for specific strains of HIV. Subtle mutations of the virus not targeted by the vaccine may survive, much as the spam blocker allows junk e-mail to pass through when it doesn't see any flagged words.

The Microsoft researchers hope to apply their antispam algorithm to HIV to calculate each possible HIV mutation. If they succeed, they can then provide HIV vaccine researchers with this data, and vaccines can include antibodies designed to kill all -- not just some -- of the mutated viruses.

Spam may prove to be the springboard for of the development of a vaccine for HIV, and strange as that may seem, this is not the first time computers working on something unrelated to medicine have helped medical researchers study the effects of disease. Read the next page to find out other ways in which the virtual world is helping epidemiologists.