Dr. David Denkenberger received his B.S. from Penn State in Engineering Science, his M.S.E. from Princeton in Mechanical and Aerospace Engineering, and his Ph.D. from the University of Colorado at Boulder in the Building Systems Program. His dissertation was on his patented expanded microchannel heat exchanger. He is an assistant professor at University of Alaska Fairbanks in mechanical engineering. He co-founded and directs the ALLiance to Feed the Earth in Disasters ( and donates half his income to it. He received the National Merit Scholarship, the Barry Goldwater Scholarship, the National Science Foundation Graduate Research Fellowship, is a Penn State distinguished alumnus, and is a registered professional engineer. He has authored or co-authored 95 publications (over 1500 citations, h-index = 18), including the book Feeding Everyone no Matter What: Managing Food Security after Global Catastrophe. His food work has been featured in over 25 countries, over 200 articles, including Science, Wikipedia, Discovery Channel Online News, Gizmodo,, and Science Daily. He has given interviews on 80,000 Hours podcast and Estonian Public Radio, WGBH Radio, Boston, and WCAI Radio on Cape Cod, USA. He has given over 90 technical presentations, including ones on food at Princeton University, Lawrence Berkeley National Lab, Sandia National Lab, Los Alamos National Lab, Cornell University, Imperial College, University College London, University of Cambridge, and University of Oxford.

Denkenberger's Comments

Case Study: Volunteer Research and Management at ALLFED

Thanks for your feedback. People inside the academic system (Joshua Pearce and myself) are advising most of this research and we publish mostly in peer reviewed journals. As for the policy engagement, we are working with government experts such as Tim Benton. You can see some of our recent policy-related work here.

Are there any public health funding opportunities with COVID-19 that are plausibly competitive with Givewell top charities per dollar?

Thanks, though it appears that the article says that China's production rate of masks has still not quite recovered to last year's rate (50 billion per year, or 137 million per day, if the above number counts all days in the year).

All Bay Area EA events will be postponed until further notice

I was thinking of short term as weeks, e.g. canceling events in March instead of waiting until April to cancel events from then on.

All Bay Area EA events will be postponed until further notice

1. Good point
2. Without sustained protective measures, we only get herd immunity after a certain number get infected, roughly 50% for R0 = 2. So I don't think short-term measures alone (e.g. earlier travel or event banning) would impact this.
3. Again, you need sustained efforts, not just a difference in short-term effort to flatten the curve.
4. Good point
5. Without 4, it appears that the outbreak would have already peaked by the time we develop, test, and scale up a vaccine
6. This is possible, but most think other countries will not take as extreme measures

So overall, this does give significant probability that short-term actions could have high impact, so they do look worth doing.

Quantifying lives saved by individual actions against COVID-19

I agree that if we have sustained protective measures, it would not only lower the peak but also reduce the total number of people exposed. However, I am defining a short-term action as doing something we would not normally do in the next few weeks, like canceling a conference or early travel bans. I think this would delay the peak, but it's not clear to me that the peak would be appreciably lower. Furthermore, this says there are about 60,000 full function ventilators and 160,000 total ventilators. If 10% percent of people are infected at the peak and 3% of those require ventilation, that would be 1 million requiring ventilation. So even in the US, and with moderate protective measures, it looks like most people would not be getting the ventilation they need (though lowering the peak will still help somewhat). Of course if the protective measures actually stopped the spread early, then that would be a big benefit.

All Bay Area EA events will be postponed until further notice

Thanks for making your model explicit. See my comment here. Basically, the crux is that if there is going to be global spread, it could be that the final mortality is independent of short-term actions. It would be great for an epidemiologist to weigh in.

Quantifying lives saved by individual actions against COVID-19

I agree that it is useful to make simple models. The consensus appears to be that there will be a global spread, so then it appears that short-term actions could have very high impact. However, one could also argue that then the end state is going to be the same, so that would mean short-term actions would have no impact. It is true if social distancing (physical distance, handwashing, gloves, masks, etc.) is maintained for the entire pandemic, then R0 falls below one sooner, so fewer people get the disease. You can see a model of this here. On the 80,000 Hours podcast, they say that reducing travel out of the place of origin by 90% in the beginning only delays the outbreak 3 weeks, likely not enough time to get a vaccine. So which one is right, a huge impact due to short-term actions or basically nothing?

Potential High-Leverage and Inexpensive Mitigations (which are still feasible) for Pandemics

Yes, this morning in Fairbanks it was -32F (-36C)!

Though many of the recommendations seem like common sense in retrospect, the reality is that these interventions are relatively neglected. We would have been better off if we had done some planning ahead of time about how to scale up personal protective equipment (PPE) such as masks. Furthermore, common sense varies. For some, it is common sense that a mask will protect you from illness, but people do not realize that the pore size of a simple polymer surgical mask is significantly larger than most evaporated cough/sneeze droplets. At the other end of the spectrum, common sense might lead you to believe that an improvised fabric mask would be ineffective because the pore size is larger than the typical surgical mask made of polymer. And indeed the median particle that is sneezed would go through a fabric mask. However, when you look at the droplet size distribution, the majority of mass (and therefore viruses) are actually contained in the larger droplets that would be stopped by a fabric mask. Similarly, common sense might lead you to believe that a glove needs to be rubber because that is how we get most of them. But if dexterity is not critical, one can use plastic (e.g. garbage bags). Another piece of common sense that I had before embarking on this project was that this PPE would just slow down the spread, but eventually everyone would get the disease, so the mortality at the end would be the same (assuming a vaccine is not developed in time). But in reality, since people who have had the disease generally have immunity, the number of people that infected person spreads to eventually falls below one, and the virus dies out, not infecting everyone. So these simple PPE interventions could actually significantly reduce overall mortality. Furthermore, if people can do more distancing early on, the spread of the virus could be stopped early, preventing a pandemic. So there really is a lot that we can do on the non-medical side.

Load More