Covid-19 is the largest health and economic crisis of our generation. We are all bombarded by a lot of news, which are evolving quickly, are often highly technical, and have policy consequences that dramatically affect our lives.

Andrea Galeotti and I felt the need to learn some tools to process this information and to understand and rationalise current health and economic policies. We created a narrative to highlight different trade-offs which are part of: a) every health policy that attempts to flatten the contagion curve of Covid-19, and b) every economic policy that attempts to flatten the 'recession curve' caused by Covid-19.

We thought to share the outcome of this exercise with you: A user guide to Covid-19.            It consists of four mini-lectures (each with slides and a video):

• A user guide of Covid-19: part I: gathering facts. [VideoSlides
Reporting the facts that are available to us all, in a way that is concise, precise and accessible to a large audience.
• A user guide of Covid-19: part II: epidemiology for dummies. [VideoSlides]
Explaining, in simple but precise terms, the epidemiology models that are guiding governmental health policies. Discussing trade-offs in health policies that implement different degrees of social distancing.
• A user guide of Covid-19: part III: economics for dummies. [VideoSlides]
Explaining, in simple but precise terms, the economic mechanisms behind the new economic crisis due to Covid-19.
• A user guide of Covid-19: part IV: policy options. [VideoSlides]
 Discussing health and economic policy options in view of the current situation.
A file containing the full set of slides is here: Lecture on Covid-19.
version of the slides in Italian can be found here. This is a rapidly evolving situation so we are updating the lecture slides (almost) daily.


At the moment, most countries are implementing strict social distancing measures. This policy choice is the outcome of two factors:
  1. A low capacity of intensive care beds of health systems (health supply);
  2. The expected high demand of critical beds due to the fast spreading of Covid-19.

Any measure of social distancing (if properly enforced) decreases the flow from healthy people to people infected by Covid-19, and so it flatten the demand for health care. Numerical analyses, based on standard and sophisticated epidemiology models, predict that only strict social distancing measures can reduce the spread of Covid-19, in a way that the capacity of national health systems is sufficient to cope with the demand.

We are convinced that, in this moment, this is the best policy to implement and we stress the importance that: everybody should follow the guidelines of the government. The spread of Covid-19 will not go down at a sufficiently fast rate unless we all understand that the behaviour of each of us, if irresponsible, will create direct costs to the most vulnerable population and, indirectly, to everyone, since economic and societal costs will escalate at a measure that is difficult to even think of.

At the same time, our reading of the information that is available to the public, made us realise the following:

A. Health policies that are currently implemented are based on incomplete and biased data. For example, most of the infections seem to be generated by asymptomatic individuals. Those individuals are less contagious relative to symptomatic patients, but they are so much more in numbers that, overall, they are the most "responsible" for the growth of the infection. If the numbers that have been estimated in different studies are correct, then it is likely that, even with strict social distancing policies, the peak of the contagion curve will be much higher than expected, as those policies have been introduced too late.

B. The benefit of strict social distancing policy is to decrease the spread of the diffusion in the short run so drastically that the capacity of the health system can cope with the demand. There is, however, a drawback of strict social distancing policies. This is that, once the restrictions are lifted, the society is still very vulnerable to Covid-19, thereby leading to likely new waves of mass population contagious.

C. It is not a feasible policy to keep strict social distancing measures until a vaccine is created. There is no need to elaborate on this, as it is obvious.

Once we put together these three points, we reached three basic conclusions:

1. The measures adopted by governments to flat the contagion curve now have an important additional benefit:

They buy-out time to allow us to develop effective strategies that contain the virus, once we are ready to relax existing measures of social distancing. 

2. The only way to develop such strategies is to collect reliable data. This means a simple thing:

Countries should test a representative sample of the population (independently of symptoms), recording socio, economical, demographic and locational characteristics at the household level.
3. With the collection of this data, we need to use standard statistical methods to:
Infer the household characteristics that are important to develop surveillance strategies.

We conclude with three points:

Firstly, there is nothing original in this proposal. We are not discovering anything new that many scientists and social scientists do not already know. However, this fact seems to have been ignored by policy makers so far.

Secondly, the implementation of the above proposal is feasible. In most countries affected by Covid-19, there are research institutes and governmental agencies that have already collected data from representative samples of the population. Data from random testing can be linked to existing data. This strategy requires us to test only a small part of the population.

Thirdly, Covid-19 can only be defeated by mobilising experts from different fields. Of course, medical research for the development of simple-to-use serological tests and the Covid-19 vaccine are priorities. However, it is also a priority to collect better data, to develop better containment strategies, and develop better social-economic policies to support all disruptions in the society created by the Covid-19 crisis.

A global crisis requires a global response.

Andrea Galeotti and Paolo Surico

*Financial support from the European Research Council and the Wheeler Institute is gratefully acknowledged. Luis Fonseca, Sarah Pavlu and Francesco Amodeo have provided excellent assistance.