As I drive home, I listen to NPR. I hear a report with one word that gives me a start … “Ebola.” I have studied influenza, so I know just enough about viruses that my heart skips a beat and I feel an instant of nothing less than terror.
I don’t scare easily, but combine a highly infectious virus, a 90-percent mortality rate, no known treatment, and you can see the problem.
So why does Ebola seem to spring up in places like Uganda or the Congo, and not in New York City? Why does it seem to stop after infecting a dozen or a 100 people, and not decimate the globe? Is this likely to continue or should we all be investing in biohazard suits?
Ebola is a virus, the simplest form of life, designed with an economy that is almost as elegant as it is ghastly. It is merely a blueprint of itself, without even the metabolic machinery for reproduction. To survive, it must hijack your cells, usually at the cost of your own survival.
Viruses like Ebola seem almost suicidal. They are so rapidly lethal that the virus doesn’t have much time to spread. The virus survives at times when no human is infected by living in an animal species that tolerates it, an animal reservoir. Less dangerous viruses, like the flu, are a little more evolved and don’t kill their host. This is a clear benefit to both influenza and the human race.
Where Ebola resides between human attacks has been the subject of much research. Get rid of the reservoir and you get rid of the virus. The best animal candidate for viral reservoirs, at this moment, is the fruit bat. The more usual suspects, such as small mouse-like rodents, have been ruled out. How does it get started in humans? A bat drops a half-eaten piece of fruit that is contaminated with bat saliva, containing the Ebola virus.
Ebola is one nasty virus. You get the usual viral symptoms: fever and chills, headache and muscle aches, and often nausea, vomiting and diarrhea. It goes rapidly downhill from there. You often develop a coagulation disorder and start bleeding from various orifices.
Major organ systems start failing, such as renal, cardio-respiratory, and neurologic. All this occurs in less than a week. Every secretion is highly infectious, including vomit, diarrhea, saliva and blood. The body remains highly contagious, even after death. The virus is passed by direct contact with the body or any of these secretions.
That is direct contact transmission. The secretions get on your face. What won’t pass the virus is its single weakness, and a great blessing for all of us. Unlike influenza, Ebola doesn’t spread by cough or by dispersal of viral particles. No one is going to infect an airplane full of people by sneezing or coughing. For that reason, Ebola is not likely to pop up in the middle of some American city.
Simple barrier protection (gown and gloves) are all you need to contain an outbreak of Ebola. These are low-tech items that are easily available and inexpensive for the remote locations where Ebola occurs.
Usually Ebola is picked up by a single member of a family living in an area near fruit bats. This infected person rapidly worsens and may transmit the virus to household members as they attempt to take care of the victim. This causes a spread to a few 100 people, and the alarm sounds.
The area is quarantined by health workers, taking full viral precautions. Medical support is provided for the victims, and a few may be lucky enough to recover. After all contaminated fluids, bedding, and deceased patients are incinerated, the outbreak is over.
Several vaccines are being developed to fight against the Ebola virus and hold promise for the future.
Ebola is ultimately a victim of its own lethality. Patients with Ebola are much too sick to travel, which limits its range. Its outbreaks are furious, but localized. One more exotic horror in a land far away.
Invest your worry time in the next influenza epidemic, which at least you have some control over. Also, don’t adopt any stray fruit bats.