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 and may now be overreacting. The Washington Post reported, for example, that 43 percent of surveyed Americans said they fear they or a family member will become an Ebola victim. If additional caregivers and family members of Ebola patients come down with the disease, Americans’ anxiety will surely escalate as their confidence in official safety assurances erodes. And there are good scientific and statistical reasons why individual Americans should be more guarded about catching the disease than the disease experts insist that they should be.
Ebola Can Spread Without Direct Contact
On September 2, the president stressed how Ebola was very different from flu: “You cannot get it from casual contact, like sitting next to someone on a bus. You cannot get it from another person until they show the symptoms of the disease, like fever.” He then noted how Ebola is most commonly spread by people coming into direct contact with “body fluids”—for example, the “sweat, saliva or blood”—of victims with symptoms. Centers for Disease Control (CDC) director Tom Frieden in mid-October endorsed the president’s message, noting: “[I]f you’re a member of the traveling public and are healthy, should you be worried that you might have gotten it [Ebola] by sitting next to someone? And the answer is no.”
These pronouncements were unequivocal, with no acknowledgement of medical science’s ever-present uncertainty. Before the first Liberian-American Ebola victim died in Dallas, these leaders assured all that they would take an “all hands on deck” approach to stopping an outbreak in this country “in its tracks.” Nice political pledges, but the immediate response from the CDC was tepid at best, with new more protective protocols (including upgraded protective gear worn by caregivers) only now emerging, months later.
Their positions have been repeated throughout the media. In its report on the second Dallas nurse to come down with Ebola, who flew home to Cleveland with a low-grade temperature (99.5 degrees), a New York Times reporter observed, “Ebola is one of the world’s most lethal diseases, but is contagious only through contact with bodily fluids,” but added a caveat: it would be “highly unlikely” the nurse’s fellow passengers were at risk.
The unavoidable inference from official statements is that victims without symptoms (yet!) cannot transmit the disease, and the “symptoms” are as straightforward as a “fever” (which remains ill-defined). Ebola can only be transmitted via “direct contact” with “body fluids” and then must enter new victims’ bodily openings. Ebola can’t be transmitted from dry surfaces of, say, doorknobs and bowling balls or invade dry skin surfaces that are not abraded, according to CDC’s initial assurances (accepted on faith, apparently, by the president, the New York Times reporter, the Dallas nurses, and even the New York City doctor who cared for Liberian Ebola patients and who apparently walked the city’s streets on his return, even while not feeling well.
These official assurances should not have passed the smell test. They contrast with the videos of Emory University’s Ebola specialists (and other caregivers and decontamination crews) who, when yards away from Ebola patients, were suited up—head to toe, with multiple layers of clothing, goggles, and respirators—with their gear appearing to be as protective as that worn by Japanese workers who in 2011 began seeking to contain the radiation leaks at the earthquake-damaged Fukushima Daiichi nuclear workers. The Emory Ebola caregivers got hosed down with chemicals on exiting the isolation rooms. They also suited up and disrobed following strict protocols, with supervisors watching.
Healthcare officials and media critics expressed some distress that one of the Dallas nurses who caught Ebola reportedly left for a time a small portion of the back of her neck exposed. This was at a time when they were assuring everyone that Ebola couldn’t be transmitted without direct contact with bodily fluids, or through dry skin.
We Were Just Following Government Orders
Dallas Health Presbyterian Hospital, including the infected nurses, made care mistakes (from which New York City’s Bellevue Hospital learned and advanced its Ebola care), but it can be forgiven, at least partially, for following closely CDC protocols at the time that all, including the CDC, now agree were more lax than they should have been. This may have been the case because CDC officials at the time they staunchly supported their original protocols believed their own press pronouncements, leading to what a former CDC veteran with 25 years of service now concedes, belatedly, “was overconfidence on every side.”
Still, news reports continue to discuss the hospital’s “missteps” in the care of the first Ebola victim, as if the caregivers knew they were making mistakes. Dallas caregivers simply followed the best advice CDC experts gave them, which has proven to be inadequate, and which no one at the time the patient walked into the emergency room thought would be the case.
Healthcare experts and the president seem to want to have it both ways: on the one hand, stressing how difficult it is for the Ebola virus to invade potential new victims and, on the other, taking precautions that suggest transmission is not, potentially, all that difficult. At the same time, officials are gradually conceding that the survivability and transferability of the virus may be greater than what they once thought.
Much of the public is now understandably skeptical of the implied message: “Don’t worry. We have your back. We know the science ‘facts’ you can rely on.” A more appropriate initial position should have been: “Our knowledge of Ebola is necessarily somewhat limited, which makes these initial cases a learning experience for us, the caregivers, and the rest of the world. Let us get back to you for better guidance when we have more experience.”
But the Ebola mess gets worse.
It Might Be Possible to Get Ebola from Sitting on a Bus
The American public has been told that people’s contact with “body fluids” must be consequential, like handling victims’ vomit or stools or blood samples, which means they can’t be infected by riding a bus (or plane or subway or cruise ship) next to victims (whether they show symptoms or not). Yet the World Health Organization has recently conceded that Ebola can indeed be transmitted “indirectly, by contact with previously contaminated surfaces and objects” (albeit with a low risk) and in water droplets in sneezes, which surely can put nearby passengers in all directions at some risk.
How can anyone now be confident that Ebola can’t be transmitted via the droplets in coughs or even from the spittle inadvertently spewed as passengers talk with one another? Might there not be enough moisture in some normal exhales to allow the virus to survive beyond “direct contact,” especially in the closed environments of airplanes where the air is rapidly circulated? The country is now learning that researchers have a more limited fix on how long the virus can last outside the body—for example, on doorknobs or in sewer systems—than the president and CDC director let on initially, which explains why victims’ quarters have being scrubbed down by hazmat crews and victims’ clothes and personal effects have been collected for burning. In covering the first New York City Ebola victim, a New York Times reporter repeated what he had learned from experts—that the Ebola virus is “fragile,” because it dries out, but, apparently, the virus can survive on dry surfaces for up to “a few hours.”
Some officials insist that their clean-up efforts have been taken out of an “abundance of caution.” Translated, the officials could be, inadvertently, admitting to excessive (if not misleading) rhetoric from which they are now trying to protect the American public.
People Who Don’t Show Symptoms Could Be Contagious
Nevertheless, the president and the CDC director have added no caveats to their pronouncements that Ebola victims are only contagious when they show “symptoms”—as if “symptoms” work like on-off switches after some fever tipping point has been crossed (which is unlikely to be definitive). The fact of diseases is that contagion varies with time and across victims in terms of symptoms.
The first Dallas Ebola patient might not have been contagious when he was sent home after his first emergency-room visit with a 103 temperature, while the nurse who took the Cleveland flight with a 99.5 temperature could have been. Two victims with the same symptoms (as measured by temperature, which is hardly a definitive diagnostic) very well might not harbor the same contagion, and the extent to which they become contagious could well escalate at different rates with their temperatures. Of course, those who come in contact with Ebola victims will also vary in their susceptibility to infection, through direct or indirect contact. The New York City doctor was found to be a victim with a temperature of 100.3. Americans can be forgiven if they now see a fever symptom as far less definitive as official pronouncements have suggested.
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.
Does Anyone Ever Know Precisely When a Fever Began?
Granted, a number of medical doctors have editorialized very recently for the New England Journal of Medicine that fever is a key first symptom for Ebola and that “[W]e now know that fever precedes the contagious stage [of Ebola by two to three days], allowing workers who are unknowingly infected to identify themselves before they become a threat to their community.” Those facts are comforting but hardly seal the argument. There is still room for concern over exactly when the fever symptoms first occurred across groups of people who will vary in the extent to which they have fevers and then recognize their fevers as symptoms of Ebola, not other diseases.
Moreover, the time gap between the fever and contagion could be shorter for some people than it was for the study group. There is simply far more room for uncertainty and risk in medical science than is being acknowledged, which is why the ambulance crew who drove the New York City doctor to the Bellevue hospital were fully suited, obviously not willing to take the chance that the doctor was still within two or three days before becoming contagious. The editorializing doctors assure readers that the public can rely on workers who care for Ebola patients monitor and report themselves immediately to isolation wards when they become febrile. The problem is that the chance of failure of some people to follow the doctor’s regimen may be low, but the consequences for any number of others can be deadly, and give rise to a substantial bill for tracking down and monitoring relevant others, and maybe isolating them.
The Question of the ‘Maximum Incubation 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 after 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.)
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.
An unheralded fact of the Ebola threat is that, according to a study from Drexel University, possibly 12 percent of infected victims never show the fever symptom during the currently recommended 21-day quarantine period. This suggests the recommended quarantine period is unduly short, and maybe dangerous for bus and plane passengers who sit next to people who have been exposed to symptomatic Ebola victims. Granted, one study does not reliably prove anything, but it does suggest taking more caution.
We Have Imperfect Ebola Detection Methods
Of course, Ebola detection methods will often be less than perfect, constrained in their precision by cost considerations and protection for the evaluators at, say, airports and bus terminals. This is why screeners now take passengers’ temperatures with laser gun-like thermometers held some distance from their temples. No one should expect that the detection equipment will operate without error, nor that the screeners will have equal skills and will perform their duties without lapses in attention (or, especially in West Africa, without lapses in integrity when people who consider themselves at some risk of coming down with Ebola symptoms but want to make it to this country to access its medical systems offer side payments).
Detection methods set to any symptomatic standard might miss people who have contacted Ebola but are not symptomatic and pass with flying colors the screening at the start of their trips only to have their condition worsen as they fly across the Atlantic or who simply make a round-trip from Dallas to Cleveland—or, most recently, take a cruise or take a private tour of New York City streets.
As all doctors understand, there is one indisputable (and inconvenient) fact of the practice of medicine: determining “symptoms” is as much art as science, with some measure of guesswork thrown in. Errors in diagnosis will occur. Patients will tell lies, as has been reported of the Liberian-American victim both when he departed from Liberia and when he first visited the Dallas emergency room.
Is it not understandable that many Americans are not willing to believe, without reservation, the president and CDC director’s assurances that contracting Ebola by sitting in crowded buses, planes, and cruise ships is all but impossible, given the dreadful consequences that are at stake? Perhaps, more revealing, would the Secret Service allow a reporter who has interviewed people in rooms with infected Ebola patients (without touching anyone’s bodily fluids) but who was not then symptomatic, as determined by their temperature, to sit next to the president aboard Air Force One? The answers are transparent.
The Ebola Virus Is Evolving
The president, Frieden, and other healthcare officials offer their pronouncements with full confidence that they know the science of Ebola, as defined by the research findings they have considered. Maybe so, but Ebola is still an aggressively evolving “variable.” This year a team of researchers has already found more than 300 genetic mutations in the Ebola genome that now “make the 2014 Ebola virus genomes distinct from the viral genomes tied to previous Ebola outbreaks,” a portion of the findings reported in Science. This means that the strain of the virus that now threatens Americans (or could threaten the country a year from now) just might be transmitted with more casual contact than in the past.
However, this evidence suggests that the president and other officials should be extra cautious in their claims, and admit that many facts are still out about exactly how this virus is spread, under what conditions, who is at risk and exactly how and why different Ebola victims react differently to the disease (with some victims getting well in short order and others having serious problems before they get well, while others die with traumatic problems). The genetic mutations cannot be summarily dismissed now because just-released research in Science suggests that genetics likely play a significant role in how susceptible mice, bred for the research, are to the Ebola virus. Experts appear to agree in reports on the research that the findings could be telling (but are hardly conclusive) on how and why humans vary in their responses to Ebola.
With hazardous-materials teams captured on camera collecting, encapsulating, and incinerating materials found in the living quarters of the American victims and then chemically scrubbing everything the victims have touched (and doing similar things with people the victims have been in contact with), is there any wonder why the public may have doubts about the veracity of official pronouncements on Ebola? Moreover, is there any wonder why paramedics in Orange County, California (and maybe all over the country), earning above minimum wage (but only $9.27 an hour!), now have reservations about making direct, or even casual, contact with 911 callers who tell operators that their “symptoms” vaguely resemble official Ebola symptoms? Should anyone expect them to risk their own and their families’ lives when they have yet to receive Ebola training and proper protective clothing?
The Relative Gravity of Ebola and Flu
True, the risk of contracting Ebola may be “very small” for healthy Americans on trains, subways, and cruise ships, but everyone now knows that the downside to Americans taking a small (or even miniscule) risk is at least 50 percent and maybe 70 percent (or greater) chance of death if they contract the disease. Put in economic jargon, the risk-discounted cost of coming down with Ebola (and being out of work for three weeks, if medical authorities determine someone has been exposed) is likely far more for, say, pizza-delivery guys than the meager tips they can expect from deliveries.
One health expert from the University of California, Irvine could be right when he observed that “the hysteria around this [the Ebola outbreak in the United States] is probably doing more damage than the actual disease.” He was also likely on target when he observed, “Frankly, flu is more serious,” as reported in an Associated Press story on the rising American fear of Ebola. Flu has killed far more Americans in the last year (with the estimated count into the thousands, according to the CDC) than Ebola (with the known U.S. death total at one, to date), but there are key differences between the country’s experience with flu and Ebola that should not be dismissed:
- First, most Americans have had considerably more experience with flu and have an understanding of its infectiousness and consequences. The Ebola cases in this country are unprecedented, which leaves open the question of the extent to which the country’s medical infrastructure is capable of handling the threat, especially if the disease is uncontained and becomes widespread.
- Second, the death rate from flu is far lower than for Ebola, in part because of the flu vaccine and well-honed medical practices for treating flu patients (an Ebola vaccine is yet two or more years away).
- Third, as argued here, Americans now have several reasons for doubting the official warnings, or lack thereof, on the exact threat of Ebola. Confidence in the country’s ability to contain any Ebola outbreak took a serious hit when a doctor could wander freely around New York City before putting himself in quarantine without alerting anyone until he self-identified signs of being infectious (and could have done so belatedly).
Ebola ‘Hysteria’ Can Make Sense
Prominent New York Times columnist Charles Blow repeated an Ebola narrative being pressed by medical scientists, that the country has been captured by an “absolute hysteria surrounding the Ebola crisis,” which is being stoked by “reactionary politicians and irresponsible media.” The narrative includes the claim that current Ebola science is right. The suggestion is that anyone who shies from even casual contact with Ebola caregivers or supports quarantines for returning West African caregivers has succumbed to irrational fear-mongering.
That said, there is a solid scientific and statistical reason that, more so than experts, individuals are more likely to overreact, if not become “hysterical” with news of additional victims and their contacts (although the vast majority of Americans have remained calm). Experts can base their risk assessments on studies of groups of people who have Ebola and who have been around victims. They can determine the “expected risk,” meaning chance, of people being infected with Ebola and dying from the disease, with the mean (or average) chance being a part of a distribution of outcomes around the mean and with a “variance” (or “standard deviation”) in outcomes that can be computed for identified groups.
In statistics, the mean and variance are two of the most used assessments of risk: the greater the mean probability of being infected, the greater the risk. Also, the greater the variance, the greater the risk. Many individuals are understandably inclined to assess their risk from a personal perspective. They can be forgiven for thinking of their risk as a 1/0 outcome: either they come down with Ebola or they don’t. If they come down with the disease, they die or live (with maybe some variation in the quality of life if they get well). Individuals are likely to have a far higher measure of variance (with a distribution for outcomes that goes all the way from 0 to 1) and thus a higher risk assessment than public healthcare officials, who may naturally be inclined to weigh heavily the probability of people in groups coming down than are individuals who have to make decisions for themselves (and close families and friends).
Individual assessments of risks and determination of protective courses of action can be informed by group statistics, but individuals can be pardoned for discounting groups’ variances when they are riding on a bus next to someone who has recently returned from treating Ebola victims in West Africa. Individuals generally have control only over their own behaviors, not those of everyone on the bus. Individuals can be expected to reduce their risks by developing their own protocols, which will likely include a heavy emphasis on avoiding people, and circumstances, where the risk of infection is even minimal (taking bus rides), not to mention high (hugging friends who have just returned from West Africa with a high fever).
No one should be surprised that ordinary Americans are more inclined to press their elected officials for greater restrictions on people who travel to and from West Africa (and other areas of the world where Ebola is rampaging) than are healthcare officials. Accordingly, New Jersey Gov. Chris Christie of New Jersey and New York Gov. Andrew Cuomo imposed (somewhat flexible) 21-day quarantines for all travelers from West Africa re-entering the country through their states’ airports, with Christie telling the New York Times, “We are no longer relying on C.D.C. standards.”
American healthcare officials have sought to calm fears of Ebola with maybe the best of intentions. Officials have been right on target when noting that Ebola is less contagious than other diseases. However, by straining “scientific facts,” and failing to acknowledge what they don’t know about Ebola, and what cannot be known, they could have had the exact opposite effect and put Americans at greater risk—and lost credibility exactly when that virtue was most needed.
Healthcare and infectious disease experts should not expect ordinary Americans to understand the details of Ebola science. Instead, they should recognize that ordinary Americans will, for the most part, tend to evaluate the consistency in official pronouncements and deeds, which can make healthcare officials and scientists their own worst enemies on Ebola policy. In short, any Ebola “hysteria” should not be seen solely as the fault of “others,” meaning politicians and media. The country’s officials and experts must accept their own share of responsibility for “overreactions.” They have inadvertently squandered many Americans’ trust through semi-transparent gaps between rhetoric and deeds.
Going forward, the country’s healthcare officials need to ensure that their Ebola rhetoric matches the science of the disease. They need to level with the public and concede that the Ebola threat, as with most major disease threats with limited medical history, includes a measure of uncertainty (as distinguished from risk) on its spreads and containment that can only be partially cleared with research and experience.
