During the latest epidemic Ebola reached the US for the first time ever – in the form of some infected medical caregivers who were brought here for treatment (or who were infected but asymptomatic when they returned to the US), one man who was ill but didn’t develop symptoms until after reaching the US, and some medical professionals who cared for him. This sounds like a lot of people – but it’s nothing compared to the tens of thousands who became ill and died in Africa. Nevertheless, it was frightening for a lot of people, primarily due to Ebola’s reputation as a horribly infectious and untreatable disease that kills 90% of its victims by melting their internal organs. The problem is that nearly all of what people “know” about Ebola is wrong – with the exception of its being highly infectious. So maybe the place to start is with some of the facts.
Color-enhanced electron micrograph of Ebola virus particles.
Thomas W. Geisbert, Boston University School of Medicine
Source: link to original
First, Ebola is, indeed, highly infectious. It only takes a few virus particles entering the body to make someone sick. This is one of the reasons for Ebola’s toll on healthcare workers – it takes only a minor slipup for them to be exposed to enough of the virus to make them ill. Similarly, family members who attend to the bodies of those who have died can also easily contract the disease (on the other hand, those who do take proper safety precautions have shown that they can work safely, even around large numbers of the badly infected). But from here, reality diverges a bit from popular knowledge. And even here – in spite of Ebola’s infectious nature – it is not as bad as what most people think (more on this in a bit).
Second, Ebola can be a hemorrhagic fever – it can cause internal bleeding and this can be deadly. But what most people don’t know is that it usually causes death due to loss of body fluids and electrolyte imbalance – all of the vomiting and diarrhea steals the body’s sodium and potassium, causing death if these aren’t replaced and brought back into balance. Checking electrolyte levels and the proper balance is a very straight-forward procedure in our hospitals, but it’s not a standard procedure in many developing nations – in nations where hospital staff might have to re-use latex gloves, washing them between patients. This is why the great majority of the Ebola patients brought to the US (and the few who became symptomatic or who contracted it here) survived.
Third, Ebola is treatable, although we have only recently developed an effective treatment for it. Maintaining an electrolyte balance is a good start, and this alone goes a long ways towards keeping patients alive. But in addition, some patients were effectively treated using antibodies from patients who had recovered from the disease – this is still an experimental treatment, though, and there is not yet an approved medicine (other than anti-viral drugs) to give to Ebola patients.
OK – now let’s get back to what worries people the most about Ebola – the “am I going to get it” concern. For example – when the American physician Craig Spencer had an eventful day in New York City before realizing he’d been infected with the disease. A large number of people panicked, worried that they might catch the disease simply by having been in the same place as the good doctor on the same day. Others had similar worries when it was found that a nurse had traveled to a family event before developing symptoms – the concern was always the same: “I was in the same place on that day – am I going to get sick and die?”
So – Ebola is highly infectious, but only to those who are directly exposed to virus-containing fluids from the body of someone who is not only infected, but who is also symptomatic. So a person might be infected for a couple of weeks before they start to develop the characteristic fever and headache – and you can’t catch the disease from them during this period. Not only that, but Ebola doesn’t spread through the air, so (unlike a cold or the flu) you can’t catch it simply by breathing the same air as someone who’s infectious. And the Ebola virus is fairly fragile – it doesn’t survive long outside the body. So unless you are directly exposed to infected body fluids from someone who is feeling the symptoms of Ebola – while the virus is still alive in those fluids – you simply don’t have to worry about catching the disease. Incidentally, this includes semen and vaginal fluids – there’s evidence that the Ebola virus can survive in these for a few months after a person has recovered from the disease; the current guidance is to refrain from any sort of sex (including oral) for at least three months.
This 1995 photograph shows sanitary procedures being
practiced in a clinic in Zaire during Ebola virus disease outbreak.
Ebola isn’t the only frightening disease that’s out there – people worry (and justifiably so) about HIV/AIDS, Legionnaire’s Disease, hantavirus, anthrax, any of the various forms of hepatitis, pandemic flu, and many others. And these can all be deadly – not to mention the fact that we don’t have a cure for many of them. But (with the exception of the flu), most of these scary diseases aren’t easily transmitted from person to person (some aren’t transmitted at all this way) and many require contact with infected body fluids. So yes, they can be bad – but they’re harder to catch than what most people would think.
Having said all of this, there’s one thing more that must be brought up. It’s almost a cliché now that we can travel almost anywhere in the world in a day or so – I’ve traveled to some fairly remote places myself (although never to Africa); most of the time in 24 hours or less and never more than a day and a half. This means that a person who was eating bushmeat (or being urinated on by a bat) yesterday can be in any of the world’s major cities today or tomorrow – long before any symptoms have a chance to arise. This is simply a fact of life, and one that we’re not likely to change. This is how the first Ebola case arrived in the US, and it’s how disease is likely to continue spreading in the future. It is highly unlikely that we’re going to start instituting quarantine procedures for all incoming travelers – likely not even for travelers arriving from places with epidemics. This is just a fact of life now. But remember – in the Middle Ages the spread of the bubonic plague was a fact of life – in that case, spread by fleas. The agent was something undreamt of – a bacterium. Eventually, with better understanding and better public health measures, we were able to control the plague (although it still crops up from time to time). One can hope that, as we develop better tools (antiviral medicines, vaccines, etc.) we can experience a similar success against not only Ebola, but whatever else crops up in the future.
So does this mean that you don’t have to worry about any of these diseases? Of course not – there are a lot of things out there that can kill us. But if you’re spending the majority of your time worrying or trying to think of ways to avoid one of these ailments, your fears might be misplaced.
Note: many thanks to Dr. Erin Stair for her kind review and thoughtful comments!
About the Author: Andrew Karam is a board-certified health physicist with 34 years of experience in his field. He has earned a BA and MS in Geological Sciences and a PhD in Environmental Science, all from the Ohio State University. He has presented over 100 invited lectures and scientific talks at meetings in the US, Europe, South America, and Asia. Dr. Karam currently works on issues related to radiological and nuclear counter-terrorism; in the past he has been in charge of radiation safety for a major research university and hospital, as a professor at the Rochester Institute of Technology, and as a private consultant. He has also undertaken a number of projects internationally, working in Kuwait, Dubai, Paraguay, Uruguay, Cambodia, Cyprus, and Lithuania – his most recent overseas project involved traveling to Japan in the immediate aftermath of the tsunami and reactor meltdowns in Fukushima. He is the author of over two dozen scientific and technical papers, over 200 encyclopedia articles on various aspects of science, and several hundred editorials, essays, and articles for a variety of publications for both scientists and the general public. He has also written 16 books, including his memoir of life on a fast-attack submarine, Rig Ship for Ultra Quiet. Dr. Karam is married with five children and he currently lives in Brooklyn.