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Saturday, November 01, 2014

Medical Science Doesn’t Support Official Rhetoric On Ebola

In early September, President Obama assured West Africans in a video address that the first defense against the spread of Ebola was to get the facts on the disease’s transmission right. The problem now facing the United States is that the president, with the support of healthcare officials, may have played loose with the science “facts,” luring many Americans—including healthcare workers at the Dallas Health Presbyterian Hospital initially at the center of the country’s Ebola threat, as well as the latest Ebola victim from New York City—into a false sense of security and increasing risks to themselves and to everyone who crossed their paths.


The science of Ebola has not been—and can’t be—fully congruent with the official Ebola rhetoric, which has suggested that key terms such as “symptoms,” “bodily fluids,” “contagion,” and “contact” are more fixed facts of science than they necessarily are. After the apparent facility with which Ebola was transmitted to nurses attending the Liberian-American Ebola patient in Dallas, many Americans have understandably lost confidence in official Ebola pronouncements ...

Read the whole thing.   Is this politics, stupidity, arrogance, incompetence, or hate?  As applied to the Obama administration , they are not mutually exclusive.


For example, just when are Ebola patients infectious?

Healthcare officials and media pundits have played “symptoms” as, again, tightly defined on-off switches: “When you have the identified symptom [at some ill-defined fever], you have Ebola and are contagious. When you don’t have the symptom, you can’t be contagious, even if you have been infected.” The New York Times reported the New York doctor checked his temperature twice a day, and when he showed a fever, he checked himself into the hospital where he was put in isolation. The doctor did what he should have, according to Doctors Without Borders in a comment to the New York Times: “Self-quarantine is neither warranted nor recommended when a person is not displaying Ebola-like symptoms.”

This suggests the doctor was only infectious when he identified his symptoms, at the time he took his temperature. Was it not possible for him to become infectious before he took his temperature, and was mingling with people on the streets of the city? Even if he had identified his symptom at the exact time he became infectious, could he have not been infectious a minute or an hour earlier? Contrary to official pronouncements, infectiousness and symptoms do not necessarily and always occur simultaneously. The long history of medical science, and common sense, suggest that some unknown count of victims are likely to be infectious some unknown amount of time before the symptoms are detected, because the active progression of the disease brings on the fever, not the other way around. This means Americans have good reason to be guarded when hearing absolute medical pronouncements on when people are infectious.

And about that 21 day observation period:

 The media continues to parrot official announcements that exposed people can be declared clear of the disease if after 21 days (the “maximum incubation period for the disease to develop,” according to the New York Times editors, and most other officials commenting on the issue), they do not show the elusive “symptoms”—as if science can, and does, pinpoint a clear demarcation in time after which exposed people can be, with virtual certainty, deemed clear of the disease, or are no longer able to transmit it to others. The process of science generally can identify (imperfectly) how likely people’s contagiousness varies with time from exposure. Typically, studies can identify something of a bell-shaped curve for the distribution of the days that people can show symptoms following their infection. In the case of Ebola, the CDC has determined that from the day of infection to ten or so days it, the count of people who exhibit symptoms rises with each passing day. The count of people exhibiting symptoms declines afterwards, perhaps approaching but never reaching zero. (That is, the “bell curve” for the distribution of when people exhibit symptoms may have a long right tail.)
According to a study from Drexel University, possibly12 percent of infected victims never show the fever symptom during the currently recommended 21-day quarantine period.
Scientists generally make a judgment call, picking a time period when contagiousness reaches an acceptably low level (medically and, sometimes, politically). This means that once the required time period has been reached, there is still likely to be some prospect, however remote, that a “small” but “acceptable” percentage of the infected people can still be symptomatic.

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