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One of my amigas especiales has a very special talent - fantastic BJ's with great visuals, touch, and sounds. She's the one that pointed out to me the importance of "confianza" (trust) in Mexico. Although we've been having fiestas together for over 2 years, the last several months we've evolved into BJ's only. It works great for me because I save her for the end of the evening when I'm too spent for anything else. Lately she's been telling me that she prefers our arrangement and that it's "mejor para ambos" (better for both). I didn't understand her Spanish well enough to get her reasons but did pick up that she was mentioning cancer. I didn't really understand what she meant until I saw this article on MSNBC. I've only included the beginning of the article. By Geoffrey Cowley
NEWSWEEK
Nov. 27 issue — Back in the 1880s, before tuberculosis had a known cause, experts attributed it to a combination of risk factors—things like depression, bad ventilation, insufficient food and “family predisposition.” One standard textbook noted expansively that “the idea of infection being a cause... still prevails in the South of Europe.”
FAST-FORWARD TO the 1980s, and you hear similar accounts of peptic ulcers. The highly touted risk factors were stress, smoking, alcohol and, of course, “genetic predisposition.” Never mind that an Australian researcher named Barry Marshall was successfully giving himself ulcers by swilling beakers of bacteria—and curing them with antibiotics. The textbooks didn’t even mention his work.
We now know that TB and ulcers are infectious conditions, caused by specific microbes and treatable with antimicrobial drugs. Yet we’re still laboring to explain most of our leading scourges—cancer, heart disease, mental illness, Alzheimer’s—with long lists of risk factors. In a compelling new book titled “Plague Time” (282 pages. Free Press. $25), Amherst College biologist Paul Ewald argues that we’re missing an obvious lesson here. Roughly translated: It’s the germs, stupid. Though genes and lifestyle are no doubt important, Ewald says, the primary causes of today’s “slow-burning plagues” are parasites—viruses, bacteria and other infectious microbes—whose long-term effects we have simply failed to recognize.
Ewald is not a virologist but a bold-minded evolutionist who, in past work, has created a whole new framework for thinking about infectious disease. To understand why microbes behave as they do, he considers their ecological incentives. Cold viruses can’t afford to be too virulent because they require mobile hosts. (A dying cold sufferer wouldn’t get around enough to infect other people.) But parasites that can survive outside their hosts don’t have to be so considerate—especially if they can travel from host to host via mosquitoes or drinking water. A dying malaria sufferer is, if anything, preferable to a healthy one from the parasite’s perspective. All the person has to do to spread infection is lie still and get bit.
In “Plague Time,” he takes a similar approach. By his reasoning, our genes shouldn’t cause much heart disease, mental illness, cancer or autoimmune disease. Genes that impede our survival tend to die out over time, as their owners fail to reproduce. By contrast, the parasites with the best tricks for exploiting us are the most likely to stay in the game. There is no question that viruses and bacteria can take up long-term residence in our bodies. Some hide deep within our cells to avoid detection by the immune system, while others disguise themselves to resemble our own tissues. And we know the consequences can be serious. Suppose the immune system catches sight of a streptococcal bug that normally evades detection by masking itself as a heart cell. As the body attacks the invader, it may demolish the organ as well.
The question is whether these chronic infections are as pervasive as Ewald suspects. Some experts would scoff at the notion, but the recent findings are impressive. “Until the 1980s,” he writes, “it was generally not appreciated that women who were suffering and dying from cervical cancer were the victims of a venereal disease epidemic.” Today it’s undeniable. Epidemiologists have puzzled for more than a century over the link between sexual promiscuity and cervical cancer. But over the past 15 years, studies have revealed that human papillomaviruses, America’s most common sexually transmitted pathogens, are present in some 93 percent of cervical tumors. Scientists have even identified the proteins that HPVs use to release the brakes on normal cell division... Now, I understand what she meants. Regards,
RickFeliz
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