"[S]ome flu experts are challenging the medical orthodoxy and arguing that for those most in need of protection, flu shots and antiviral drugs may provide little to none....
When Lisa Jackson, a physician and senior investigator with the Group Health Research Center, in Seattle, began wondering aloud to colleagues if maybe something was amiss with the estimate of 50 percent mortality reduction for people who get flu vaccine, the response she got sounded more like doctrine than science. “People told me, ‘No good can come of [asking] this,’” she says. “‘Potentially a lot of bad could happen’ for me professionally by raising any criticism that might dissuade people from getting vaccinated, because of course, ‘We know that vaccine works.’ This was the prevailing wisdom.”
The history of flu vaccination suggests other reasons to doubt claims that it dramatically reduces mortality. In 2004, for example, vaccine production fell behind, causing a 40 percent drop in immunization rates. Yet mortality did not rise. In addition, vaccine “mismatches” occurred in 1968 and 1997: in both years, the vaccine that had been produced in the summer protected against one set of viruses, but come winter, a different set was circulating. In effect, nobody was vaccinated. Yet death rates from all causes, including flu and the various illnesses it can exacerbate, did not budge...
The most vocal—and undoubtedly most vexing—critic of the gospel of flu vaccine is the Cochrane Collaboration’s Jefferson, who’s also an epidemiologist trained at the famed London School of Tropical Hygiene, and who, in Lisa Jackson’s view, makes other skeptics seem “moderate by comparison.” Among his fellow flu researchers, Jefferson’s outspokenness has made him something of a pariah....
“Tom Jefferson has taken a lot of heat just for saying, ‘Here’s the evidence: it’s not very good,’” says Majumdar. “The reaction has been so dogmatic and even hysterical that you’d think he was advocating stealing babies.” Yet while other flu researchers may not like what Jefferson has to say, they cannot ignore the fact that he knows the flu-vaccine literature better than anyone else on the planet. He leads an international team of researchers who have combed through hundreds of flu-vaccine studies. The vast majority of the studies were deeply flawed, says Jefferson. “Rubbish is not a scientific term, but I think it’s the term that applies.” Only four studies were properly designed to pin down the effectiveness of flu vaccine, he says, and two of those showed that it might be effective in certain groups of patients, such as school-age children with no underlying health issues like asthma. The other two showed equivocal results or no benefit.
Flu researchers have been fooled into thinking vaccine is more effective than the data suggest, in part, says Jefferson, by the imprecision of the statistics....As with vaccines, the scientific evidence for Tamiflu and Relenza is thin at best. In its general-information section, the CDC’s Web site tells readers that antiviral drugs can “make you feel better faster.” True, but not by much. On average, Tamiflu (which accounts for 85 to 90 percent of the flu antiviral-drug market) cuts the duration of flu symptoms by 24hours in otherwise healthy people. In exchange for a slightly shorter bout of illness, as many as one in five people taking Tamiflu will experience nausea and vomiting. About one in five children will have neuropsychiatric side effects, possibly including anxiety and suicidal behavior....
Why, then, has the federal government stockpiled millions of doses of antivirals, at a cost of several billion dollars? And why are physicians being encouraged to hand out prescriptions to large numbers of people, without sound evidence that the drugs will help? The short answer may be that public-health officials feel they must offer something, and these drugs are the only possible remedies at hand. “I have to agree with the critics the antiviral question is not cut-and-dried,” says Fauci. “But [these drugs are] the best we have.” The CDC’s Nancy Cox also acknowledges that the science is not as sound as she might like, but the government still recommends their use. And as with vaccines, she considers additional randomized placebo-controlled trials of the antiviral drugs to be “unethical” and thus out of the question....
The annals of medicine are littered with treatments and tests that became medical doctrine on the slimmest of evidence, and were then declared sacrosanct and beyond scientific investigation. In the 1980s and ’90s, for example, cancer specialists were convinced that high-dose chemotherapy followed by a bone-marrow transplant was the best hope for women with advanced breast cancer, and many refused to enroll their patients in randomized clinical trials that were designed to test transplants against the standard—and far less toxic—therapy. The trials, they said, were unethical, because they knew transplants worked. When the studies were concluded, in 1999 and 2000, it turned out that bone-marrow transplants were killing patients. Another recent example involves drugs related to the analgesic lidocaine. In the 1970s, doctors noticed that the drugs seemed to make the heart beat rhythmically, and they began prescribing them to patients suffering from irregular heartbeats, assuming that restoring a proper rhythm would reduce the patient’s risk of dying. Prominent cardiologists for years opposed clinical trials of the drugs, saying it would be medical malpractice to withhold them from patients in a control group. The drugs were widely used for two decades, until a government-sponsored study showed in 1989 that patients who were prescribed the medicine were three and a half times as likely to die as those given a placebo....
As it stands, more than 50 percent of health-care workers say they do not intend to get vaccinated for swine flu and don’t routinely get their shots for seasonal flu, in part because many of them doubt the vaccines’ efficacy....
“There’s no worse place to go than the hospital during flu season,” says Majumdar. Those who don’t have the flu are more likely to catch it there, and those who do will spread it around, he says. “But we don’t tell people this.”
All of which leaves open the question of what people should do when faced with a decision about whether to get themselves and their families vaccinated. There is little immediate danger from getting a seasonal flu shot, aside from a sore arm and mild flu-like symptoms. The safety of the swine flu vaccine remains to be seen. In the absence of better evidence, vaccines and antivirals must be viewed as only partial and uncertain defenses against the flu. And they may be mere talismans. By being afraid to do the proper studies now, we may be condemning ourselves to using treatments based on illusion and faith rather than sound science."
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