Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, February 6, 1992 TAG: 9202060023
SECTION: EXTRA PAGE: E-1 EDITION: METRO
SOURCE: Joel Achenbach
DATELINE: LENGTH: Long
TREATMENT FOR AIDS MORE LIKELY THAN CURE
Q: Why is AIDS so hard to cure?A: People have a paradoxical attitude toward science: On the one hand we are annoyed by the know-it-all attitude of many physicists, biologists, psychologists, by their arrogance, their impersonal delivery of information; and yet we insist they solve every last medical problem that might strike us down.
We have unlimited faith in medical science. Surely there is nothing that can't be figured out eventually, with enough money and gumption. Scientists cured polio, so we figure they ought to be able to cure AIDS. It's caused by a virus, after all, and we imagine viruses as very tiny bugs that can be rooted out and exterminated.
The truth is that the Human Immunodeficiency Virus is much harder to attack than the polio virus, and it is quite possible that a "cure," strictly defined, will never be found. Not in 10 years, not in 20 years, maybe never. The virus, says Dr. Nava Sarver of the AIDS division of the National Institute of Allergy and Infectious Diseases, "is probably the most difficult [virus] the scientific community has ever encountered."
Here are a few of the reasons a cure for HIV is so difficult:
1. The virus changes. Even within one person, the virus can mutate in a matter of hours. This is partly because the virus is sloppy at reproducing itself, and makes inaccurate copies. These errors work to the virus' advantage - it is a moving, shifting target for the body's immune system and for any potential vaccine.
"It may be like the cold virus in that we may never get a vaccine that works," says Bob Rubin, a cell biologist at the University of Miami, which has an extensive program in AIDS research.
Like HIV, cold viruses change constantly. So too with the flu virus - every year it undergoes a slight alteration, called a genetic drift, and roughly every 10th year it changes more drastically, a genetic "shift." (Why? According to Dr. Parker Small of the University of Florida, this shift may occur when someone already infected with flu is coughed on by an animal with a different strain of the virus. The two viruses then fuse, in a sense, to form a new and more lethal strain of flu.)
2. HIV, unlike most viruses, is able to become part of the genetic code of a cell, to integrate itself into the very brains of a cell's operation, the DNA. You have to kill the cell in order to save it. Polio, by contrast, remains outside the cell's genetic machinery, and is easier to target.
The reason you can't simply try to kill all the HIV-infected cells is:
3. HIV infects the entire body. If it was just in the blood, you might be able to clean it out. "But the virus is also present in the tissue, in the brain, in the pancreas, in the lungs. . . . You can't get to it very easily, it's not accessible," says Sarver.
The good news is that drug therapy has succeeded in slowing down the progress of the disease in many patients. Over time, a multipronged attack against HIV may neutralize it to the point that it does not radically alter the normal life expectancy of an infected person. This is where many researchers are looking: not a miracle cure, but a relentless counterattack.
"I don't think it's going to be cured, I think we're going to find a treatment for it, a very good treatment," says Sarver.
And we trust her on this. She's a scientist, after all.
Q. Why are "doggie treats" such treats?
A. The main thing you need to know is that when a dog food company boasts that there is "real meat" in a dog biscuit, they are talking about lungs. Or liver. Or spleen. Or heart. Stuff humans don't eat.
In dog "treats," the meat gets "emulsified" and mixed in with the flour, along with, in some cases, more sugar than is found in your average dog food pellet. That's why dogs like treats. More meat than normal dog food, which often has none at all. More fatty stuff. More sugar sometimes. Often they are sprayed with enzymically digested meat, which the industry refers to simply as "digest."
Strangely, the dog food industry defines a "treat" in negative terms. It says that it is not nutritionally balanced, unlike standard dog food, which is fortified with vitamins. So by calling it a "treat" the dog food companies are really saying "junk food."
"It's very similar to humans eating candy instead of a balanced diet," says Nancy Kippenhan, spokeswoman for ALPO Pet Foods.
Treats are a trend, we learned.
"Treats are the fastest growing category in the dog food market," says Mark Finke, ALPO's director of nutrition. "Because people are treating their dogs more like humans, more like children, and they want to give them something other than plain old food."
What does dog food actually taste like? "We don't encourage people to eat it," said Kippenhan. "But it's sterilized, so it actually would be safe, quote unquote, for people to eat. But it's not all that appetizing. It tastes blander because there's not as much salt and flavoring as there is in human food."
Though with a touch of Tabasco, it's probably deLISH.
Washington Post Writers Group
Joel Achenbach writes for the Style section of The Washington Post.