Testing for coronavirus infections and antibodies: Views of leading economists on the need for increased capacity to prepare for ending lockdowns

Romesh Vaitilingam 10 April 2020



The lockdowns in place around the world to limit the contagion of Covid-19 have been implemented without reliable information on the spread of the disease or the prevalence of the novel coronavirus in the population. Several economists and other researchers have commented on the importance of testing (e.g. Baldwin 2020, Dewatripont et al. 2020, Galeotti and Surico 2020, Gros 2020, Stock 2020b, 2020c).

The IGM Forum at Chicago Booth, which, for nearly a decade, has been regularly polling some of the world’s top economic experts in the US and Europe for their views on topical issues of public policy, invited its US panel to express their views on the role of testing for infections and antibodies to inform decisions about easing measures on social distancing and allowing public activities to restart.

Following the standard format of the IGM polls, the experts were asked whether they agreed or disagreed with the following statements, and, if so, how strongly and with what degree of confidence:

a) Even if tests for Covid-19 are being rationed, there is an urgent need for some random testing to establish baseline levels of the virus to inform any decisions about ending lockdowns.

b) Required elements for an economic ‘restart’ after lockdowns include a massive increase in testing capacity (for infections and antibodies) along with a coherent strategy for preventing new outbreaks and reintroducing low-risk/no-risk individuals into public activities.

Of the 44 US experts, 42 participated in this survey and the balance of opinion on the two statements are summarized below. More details on the experts’ views come through in the short comments that they are able to make when they participate in the survey.

Several provide links to relevant research evidence and commentary, including the web page set up to collect policy proposals for mitigating the economic fallout from COVID-19 written by the network of economists associated with the IGM Forum (many of them also associated with CEPR), and the analyses of Covid economics published at VoxEU.

Random testing to establish baseline levels of the virus

On the first statement, weighted by each expert’s confidence in their response, 66% of the panel strongly agree, 27% agree, 3% are uncertain, and 4% disagree. Among the comments of the overwhelming majority who agree on the need for random testing, several experts note the importance of better information.

Christopher Udry (Northwestern) warns: ‘The lack of reliable information on the distribution of the virus makes decision-making riskier.’ Larry Samuelson at (Yale) says: ‘Lockdowns should be ended scientifically rather than blindly; to do so we must know the state of the population, which requires testing.’ Robert Hall (Stanford) adds: ‘We need one survey of a few thousand people with repeated testing and clinical observation, to clear up a lot of mysteries.’

William Nordhaus (Yale) is emphatic: ‘This is one of the most important holes in current policy. Absolutely critical. Some firms, hospitals can do while waiting for government.’ Aaron Edlin (Berkeley) explains: ‘Testing could help us understand prevalence and mortality risk, both overall and by age and condition. 

James Stock (Harvard) refers to his recent paper on random testing to inform critical policy choices (Stock 2020a), which concludes: ‘decisions that could save millions of lives or prevent an economic catastrophe with effects that will ripple for decades hinge on the lack of data to estimate a single parameter – how widespread this virus really is.’ 

Several experts mention testing for antibodies as well as infections. Robert Shimer (Chicago) says: ‘Antibody testing on a random sample of the population would also be very useful.’ Bengt Holmstrom (MIT) concurs: ‘Foremost we need antibody testing to judge the path of the pandemic.’

Of the small minority of panellists who say they are uncertain or disagree with the need for random testing, David Cutler (Harvard) comments: ‘We need to make sure we can test symptomatic people.’ Jose Scheinkman (Columbia) says: ‘Not while asymptomatic health workers treating Covid-19 patients cannot be tested’, referencing a New York City testing programme (NYC Health and Hospitals 2020).

Markus Brunnermeier (Princeton) argues: ‘There must be smarter ways to correct for the bias than pure random testing and not using limited resources to people who need it most.’ Angus Deaton (Princeton), who strongly agrees with the statement, adds the caveat: ‘Population testing is the point. We should, ideally, test everyone. Random is not really the point.’

Increased testing capacity to prepare for ending lockdowns

On the second statement about the need for an increase in testing capacity as part of a clear strategy for an economic restart, there is near unanimity. Again weighted by each expert’s confidence in their response, 78% of the panel strongly agree, 21% agree; one panellist is uncertain, and none disagree.

In comments, William Nordhaus says: ‘This is not macro policy; this is good public health policy. Orders of magnitude smaller than stimulus needs.’ Bengt Holmstrom notes: ‘The Asian experience shows this is a viable, hopefully sustainable path. Aiming for herd immunity always was a much riskier strategy.’ And Larry Samuelson warns: ‘Restarting too early risks a viral resurgence; too late entails extra cost. Careful planning is required to strike the right balance.’

Several experts refer to the need for testing to get people back to work. Austan Goolsbee (Chicago) asks: ‘Do you want people to get out of their pyjamas and back to work? Then we NEED TO DO MORE TESTS.’ Richard Schmalensee (MIT) states: ‘There is clearly a need for testing, not just capacity, as well as a way for low/no-risk individuals to credibly identify themselves.’ And Aaron Edlin suggests: ‘Certifying people as recovered would be extremely helpful’, linking to his summary of the idea written with Bryce Nesbitt (Edlin and Nesbitt 2020).

Other panellists provide links on ways to think about getting the economy safely back to work, including a model with testing and conditional quarantine (Berger et al. 2020, Kotlikoff and Kotlikoff 2020, Romer and Garber 2020).

Some nuance to the general agreement on this statement comes from James Stock, who says: ‘The only caveat is if we already have a high infection rate (low death rate), then such measures should target the most at risk – for example, the elderly.’ Steven Kaplan (Chicago) adds: ‘It would also be very helpful to have treatments that can be administered when symptoms first appear that reduce the odds of becoming critical.’

The one expert who reports being uncertain about the statement, Richard Thaler (Chicago), is not convinced by the suggestion that testing and the other measures are ‘required’: ‘Important yes but would I hold up restart if cases are low but tests are still rationed? No.’ Christopher Udry agrees with the statement but also points out: ‘“Required” may be too strong. A vaccine or treatment could substitute for testing. But most likely, a massive increase in testing needed.’


Baldwin, R (2020), ‘COVID-19 testing for testing times: Fostering economic recovery and preparing for the second wave’, VoxEU, 26 March.

Berger, D, K Herkenhoff and S Mongey (2020), ‘An SEIR Infectious Disease Model with Testing and Conditional Quarantine’, BFI Working Paper.

Dewatripont, M, M Goldman, E Muraille and J-P Platteau (2020), ‘Rapidly identifying workers who are immune to COVID-19 and virus-free is a priority for restarting the economy’, VoxEU, 23 March.

Edlin, A, and B Nesbitt (2020), ‘The “certified recovered” from Covid-19 could lead the economic recovery’, STAT News, 6 April.

Galeotti, A, and P Surico (2020), ‘Why testing a representative sample of the population must be done now’, VoxEU, 8 April.

Gros, D (2020), ‘Creating an EU “Corona Panel”: Standardised European sample tests to uncover the true spread of the coronavirus’, VoxEU, 28 March.

Kotlikoff, L and M Kotlikoff (2020),  ‘How to get the economy safely back to work in just 2 weeks’, The Hill, 31 March.

NYC Health + Hospitals (2020), ‘NYC Health + Hospitals Will Offer Free COVID-19 Tests to Its Health Care Workforce’, 1 April.

Romer, P and A Garber (2020), ‘Will Our Economy Die from Coronavirus?’, New York Times, 23 March.

Stock, J (2020a), ‘Data Gaps and the Policy Response to the Novel Coronavirus’, Covid Economics (forthcoming).

Stock, J (2020c), ‘Data needs for shutdown policy’, VoxEU, 4 April.

Stock, J (2020c), ‘Random Testing Is Urgently Needed’, 23 March.



Topics:  Covid-19

Tags:  COVID-19, coronavirus, testing, lockdown

Writer and media consultant, member of Vox editorial board


CEPR Policy Research