Prof. Amnon Shashua: From Mobileye to COVID-19

By Shlomo Maital

Prof. Amnon Shashua

    Many years ago, Hebrew University Computer Science Professor Amnon Shashua attended a computer vision conference in Europe. Automobile executives there asked him, how many cameras are needed on a car, to warn of danger? The prevailing wisdom: at least two, because we need two eyes for depth perception (through ‘triangulation’). Shashua said, no, we need just one camera. It can measure depth by comparing data at two points in time…   The executives scoffed. Shashua came home to Israel, and launched Mobileye, which saves lives through its little camera and sophisticated software. Mobileye was acquired by Intel for $15 b. Shashua continues to head it.  

     With the outbreak of COVID-19, Prof. Shashua has tackled the issue of strategy.   His claim: Mathematics has the answer. In the online magazine Medium, he and Shai Shalev-Shwartz have published their mathematical analysis of three different strategies, and they recommend one of them. The title asks the key question: “Can we contain COVID-19 without locking down?”.   Here is a summary. *

     “We present an analysis of a risk-based selective quarantine model where the population is divided into low and high-risk groups. The high-risk group is quarantined until the low-risk group achieves herd-immunity. We tackle the question of whether this model is safe, in the sense that the health system can contain the number of low-risk people that require severe ICU care (such as life support systems).

   “ One could consider three models for handling the spread of Covid-19.

*   Risk-based selective Quarantine: Divide the population into two groups, low-risk and high-risk. Quarantine the high-risk and gradually release the low-risk population to achieve a managed herd immunity of that population.

*   Containment-based selective quarantine: Find all the positive cases and put them in quarantine. This requires an estimation of the “contagious time interval” per age group, then given this time interval one could recursively isolate all the individuals at risk from a person that is carrying the virus using “contact tracing”. Another tool is predictive testing using contact-tracing to identify people with many contacts with other people and perform tests on them.

* Countrywide (or region-wide) lock-down until the spread of the virus is under control. The lock-down could take anywhere from weeks to months. This is the safest route but does not prevent a “second wave” from occurring.

     “In the event a risk-based quarantine approach would be contemplated by decision-makers, the purpose of this document is to provide decision-makers a formal and tight bounds to investigate whether the health system can cope with the number of severe cases that would reach ICU. Embedded in the reasoning is the idea of selective quarantine (based on age groups and existing pre-conditions, but could be any other criteria) where the ”high-risk” group (the one we suspect will have a high rate of severe cases) is quarantined and the other is allowed to spread the virus under certain distancing protocols. The underlying premise is that a full population-wide quarantine is not a solution in itself — it is merely a step to buy time followed by a more managed (non brute-force) approach. The managed phase underlying our thinking is to create herd immunity of the low-risk group in a controlled manner while keeping the economy going. It is all about keeping the health system in check and not overwhelming its capacity to handle severe cases. The question we ask in this document is whether we can estimate in advance, through sampling, that the number of severe cases arising from the low-risk group would not overwhelm the system?

   “…When the high-risk group is released from isolation they would be facing a largely immune population thus naturally facing a very slow spread of infection with a good chance to whither the storm until a cure or vaccine is available. In all other selective quarantine models the high and low risk are equally susceptible to be infected so that even if the health system is not overwhelmed still the mortality of the high-risk group is likely to be higher than the risk-based model.”

     This model has been proposed before by Nobel Laureate Paul Krugman (see my blog on his proposal, April 2).   Shashua serves on an advisory board in Israel, advising Health Ministry officials. I believe his ideas are being implemented, though cautiously.

     Warning: the article whose URL is given below can be dangerous to your health; it is highly mathematical.