It occurs to me to wonder once again where and what the natural resevoir of EVD is.
How did this particular strain get to West Africa which has never had an Ebola outbreak that was ever detected?
Have any of you encountered any new guesses from researchers?
The time span and scattered earlier outbreaks suggests it might not lie totally in bats or other mammals. If it’s not carried in mammals for a period of time then any guesses as to where this tiny monster lurks and thrives?
And if fruit bats are a natural carrier, how do they acquire it?
Where was it before 1976?
If viruses can’t travel or even move on their own what sustains it between being acquired by bats or whatever?
The burn out of the previous outbreaks was not due to human efforts but because of a natural break in the chain of contact and IIRC the reduced virulence of x generations of the transmitted virus.
I guess I assumed that the current transmission vector via diarrhea was because of virus contaminated blood in the feces but now, maybe not.
One very ugly mystery.
While there has been investigations into the question What is the reservoir since 1976, the answer is still a mystery.
As to the current outbreak, IIRC, someone who was exposed and developed the disease, traveled to a heavily populated area which also have International travel.
At one point the fight turned the curve, people thought they were out of the woods, dismantled a lot of the temporary treatment centers, and in started spreading again.
I also read about a number of false negatives, where people tested negative for Ebola and were sent home, only to return a few days later after exposing more people and returning later even sicker.
When contact is not sufficiently restricted, the virus can spread exponentially, and quickly get out of hand. Old fashioned quarantines work. No one in or out. With no space in hospitals, that should mean the old fashioned method of marking the houses, and making people quarantine in place.
That is clearly not happening either in the countries where it is out of hand, and in preventing its spread to the USA - there’s no quarantine from the countries involved to stop entry from the USA.
Earlier outbreaks were in rather isolated villages, quarantines were easily enforced, and eventually the contagion was brought to a halt.
I am intrigued by the canine link. Although it's only one study, it seems to me that a dog scavenging for food (they don't feed Blue Buffalo or anything else in that part of the world) and consuming an infected animal, then returning to the village and interacting with humans is a more likely scenario than many I've heard. I've read speculation that this outbreak began when the two year old index case supposedly ate a fruit that had been dropped by an infected bat. Which is more likely: a two year old picking up that one bit of infected fruit among many uninfected fruits or a two year old playing with a dog that had eaten an infected animal? I think the dog is the more likely scenario but don't know anything definitive.
Others speculate that the mother splashed the two year old with bat blood while butchering. We'll never know what happened because the mother, sister and grandmother are all dead of Ebola.
The dog intermediary is speculation, of course.
Where was it before 1976?
Quite likely, Ebola has been infecting people in isolated central African villages for much longer than we know. The discovery came about due to Belgians who brought the outside world in to investigate.
There is still doubt about where any virus originated. I've seen scientists speculate that viruses are bits of genetic material shed by humans/animals that just happen to have the right combination of genes to result in replication when engulfed by cells. No one really knows.
There is much we don't know about the microscopic world.
The previous outbreaks were in rural areas.
Imagine 'Captain Tripps' in a small US town a hundred years ago (No, not 10,000 people, more like 200). People were not as mobile, and by the time the disease was discovered (first cases symptomatic), the whole town (or nearly so) had it. Before spreading it to neighboring towns, those who were going to die, died.
That pretty much put an end to the other outbreaks, with some help from doctors (once the disease was recognized) and others limiting travel.
This outbreak made it to the big city, and a much more mobile population.
The current policy of leaving our borders open to the disease, exposing our large and highly mobile population to a disease with a long incubation period and highly lethal results is patent insanity.