Ebola. So Little Risk, So Much Worry

if you really want to protect Americans from viral infections, ban travel to highly unvaccinated Marin County, CA

- Michael Eisen @mbeisen

Ebola, as I have noted elsewhere, is talking up a fair amount of my time. Not any active cases, but the preparation. A disease with a 70% mortality rate needs preparation even if the chances are currently extremely small that a case will wander into one of our ERs.

While Ebola is a catastrophe for West Africa, it currently doesn’t represent much of an risk for the US. Two cases in 7 months acquired in the US with a population of 300,000,000 and those hospital acquired due to a breakdown in infection control. To date one case from Western Africa has made it the US undetected. Not impressive spread. Fortunately Ebola is not that contagious compared to other infectious diseases. I also suspect most of those suffering most from the Ebola are far too poor to afford an airline ticket to the US.

And so it boggles my mind that

10—39 percent—of U.S. adults are “concerned” that there will be a large outbreak here . More than a quarter—26 percent—are concerned that they or someone in their immediate family may get sick with Ebola this year.

They are probably more likely to win the lottery. Computer modeling, and there are always issues with models, suggest the risk is tiny:

There could be as many as two dozen people in the U.S. infected with Ebola by the end of the month, according to researchers tracking the virus with a computer model. The actual number probably will be far smaller and limited to a couple of airline passengers who enter the country already infected without showing symptoms

Not that anyone evidently believes it. Compared to other infections, Ebola is not yet in the same league with the more common infections.

UNICEF estimates that 9.7 million children under 5 die each year of preventable diseases. That’s 25,000 every day, compared to less than 2000 who have died from this Ebola outbreak--the worst outbreak ever. Across the globe, a bad flu season can kill over 250,000 people. Measles and cholera both kill over 100,000. Diarrheal diseases kill 1.5 million. In terms of global killers, Ebola just isn’t in the same class.

The fear is so out of proportion to the risk.

There was a interesting article in the Quarterly Journal of Economics, Propaganda and Conflict: Evidence from the Rwandan Genocide where they looked at the correlation between

mass media in times of conflict and state-sponsored mass violence against civilians. We use a unique village-level dataset from the Rwandan Genocide to estimate the impact of a popular radio station that encouraged violence against the Tutsi minority population.

They found

The results show that the broadcasts had a significant impact on participation in killings by both militia groups and ordinary civilians. An estimated 51,000 perpetrators, or approximately 10 percent of the overall violence, can be attributed to the station. The broadcasts increased militia violence not only directly by influencing behavior in villages with radio reception, but also indirectly by increasing participation in neighboring villages. In fact, spillovers are estimated to have caused more militia violence than the direct effects. Thus, the paper provides evidence that mass media can affect participation in violence directly due to exposure, and indirectly due to social interactions.

I wonder. Could mass media affect participation in Ebola hysteria directly due to exposure, and indirectly due to social interactions? Nah.

But at least some of the above authors have a sense of humor: