Ebola virus reality check- it has been here in the past

Transcending the Ebola virus with facts.

It’s odd to see otherwise pretty rational folks getting nervous about the news that the American Ebola patients are being treated in American hospitals.  

There are irrational fears about “What if Ebola gets out?” “What if it infects the doctors/pilots/nurses taking care of them?” “I don’t want Ebola in the United States!”  

Irrational fears are now extending to extreme reactions about "closing borders" with all countries where Ebola is reported, especially west African nations.  

Americans have overreacted to the risk of Ebola virus exposure, but with some justification. Even infectious disease experts won't provide 100 percent assurance about how to prevent transmission. 
Unfortunately, the mismanagement of Mr. Duncan's diagnosis by Texas Health Presbyterian staff in Dallas exposed dozens of people to the Ebola virus.  In fact, Mr. Duncan was infectious because he was experiencing symptoms of the disease when he was turned away from the emergency department at his first visit. Later, he traveled to the ED by ambulance, where he died in an isolation room.  Dozens of caregivers were unnecessarily exposed to the virus, as a result.

Nevertheless, it turns out, the Ebola virus has been in the US prior to the cluster of infections reported in Dallas Texas, after Mr. Duncan died and two nurses became infected from the virus.

Medical Examiner blog reports about the rare incidents of other highly infectious virus outbreaks, including Ebola.

How to contain the deadly hemorrhagic fevers that occasionally reach the United States, by Tara C. Smith.

This article originally appeared in the blog Aetiology.

It’s odd to see otherwise pretty rational folks getting nervous about a disease as rare as Ebola.  “What if Ebola gets out (in the US)?” “What if it infects the doctors/pilots/nurses taking care of them?” “I don’t want Ebola in the United States!”

Guess what?  Ebola has already been in the US.  

Ebola is a virus with no vaccine or cure. Any scientist who wants to work with the live virus needs to have biosafety level 4 facilities (the highest, most secure labs in existence, abbreviated BSL-4) available to them. We have a number of those here in the United States, and people are working with many of the Ebola types here. Have you heard of any Ebola outbreaks occurring here in the United States? Nope. These scientists are highly trained and very careful, just like people treating these Ebola patients and working out all the logistics of their arrival and transport.

Second, you might not know that we’ve already experienced patients coming into the United States with deadly hemorrhagic fever infections. We’ve had more than one case of imported Lassa fever, another African hemorrhagic fever virus with a fairly high fatality rate in humans (though not rising to the level of Ebola outbreaks). One occurred in Pennsylvania, another in New York, a previous one in New Jersey a year ago. 

All told, there have been at least seven cases of Lassa fever imported into the United States—and those are just the ones we know about, people who were sick enough to be hospitalized, and whose symptoms and travel history alerted doctors to take samples and contact the Centers for Disease Control and Prevention. It’s not surprising this would show up occasionally in the United States, as Lassa causes up to 300,000 infections per year in Africa.

How many secondary cases occurred from those importations? None. Like Ebola, Lassa is spread from human to human via contact with blood and other body fluids. It’s not readily transmissible or easily airborne, so the risk to others in U.S. hospitals (or on public transportation or other similar places) is quite low.  (In public health language, the concept of "not readily" means it's difficult, but not impossible, for the Ebola and Lassa viruses to be airborne....)
Also, there's an imported case of Ebola’s cousin virus, named Marburg. One of those was diagnosed in Colorado in 2008, in a woman who had traveled to Uganda and apparently was sickened by the virus there. Even though she wasn’t diagnosed until a full year after the infection (and then only because sherequested that she be tested for Marburg antibodies after seeing a report of another Marburg death in a tourist who’d visited the same places she had in Uganda), no secondary cases were seen in that importation either.

And of course, who could forget the identification of a new strain of Ebola virus within the United States. Though the Reston virus is not harmful to humans, it certainly was concerning when it was discovered in a group of imported monkeys. So this will be far from our first tango with Ebola in this country.

Ebola is a terrible disease. It kills many of the people that it infects. It can spread fairly rapidly when precautions are not carefully adhered to: when cultural practices such as ritual washing of bodies are continued despite warnings, or when needles are reused because of a lack of medical supplies, or when gloves and other protective gear are not available, or when patients are sharing beds because they are brought to hospitals lacking even such basics as enough beds or clean bedding for patients. But if all you know of Ebola is from The Hot Zone or Outbreak, well, that’s not really what Ebola looks like. I interviewed colleagues from Doctors without Borders a few years back on their experiences with an Ebola outbreak, and they noted:

As for the disease, it is not as bloody and dramatic as in the movies or books. The patients mostly look sick and weak. If there is blood, it is not a lot, usually in the vomit or diarrhea, occasionally from the gums or nose. The transmission is rather ordinary, just contact with infected body fluids. It does not occur because of mere proximity or via an airborne route (as in Outbreak if I recall correctly). The outbreak control organizations in the movies have no problem implementing their solutions once these have been found. In reality, we know what needs to be done, the problem is getting it to happen. This is why community relations are such an issue, where they are not such a problem in the movies.

So, sure, be concerned. But be rational as well. Yes, we know all too well that public health and hospitals can make mistakes. 

Although there's no such thing as a "zero chance of something going wrong", the risk of catching Ebola in the US is low.

It's far easier to become ill with influenza or many other “ordinary” viruses than Ebola. 

Tara C. Smith, an associate professor of epidemiology at Kent State, studies zoonotic diseases* and blogs at Aetiology, discussing causes, origins, evolution and implications of disease and other phenomena.

*A zoonotic disease is a disease that can be passed between animals and humans.