The OECD states that testing for COVID-19 is a crucial part of any plan to lift confinement restrictions and prepare for a possible new wave of viral infections. They are looking into how testing strategies can be used to achieve three main goals:

1) suppressing the resurgence of local outbreaks;

2) identifying people who have developed some form of immunity and can safely return to work;

3) gaining intelligence on the evolution of the epidemic, including on when a threshold for herd immunity has been reached.

In their communication "Testing for COVID-19: A way to lift confinement restrictions", they explain the two different types of test and what needs to be done for their implementation:. 

First, molecular diagnostic testing (RT-PCR) helps to identify those individuals who are infected at the time of the test. An effective strategy that tests, tracks people infected and traces their contacts (TTT), helps to reduce the spread of the virus and thus bring its reproduction number below one. Given the characteristics of this coronavirus – including the large number of asymptomatic cases and high reproduction number – to be effective at suppressing the spread of the virus, the TTT strategy should be used very widely, requiring a very large proportion of all cases (between 70 and 90%) to be traced to prevent a new outbreak of the virus.

The second type of test – so-called serologic test – detects people who have had a prior infection and thus developed antibodies. Such tests can be used for two purposes, namely to allow people who have acquired immunity to return to work safely, and to provide intelligence on the evolution of the epidemic across the population. Rapid serology test kits need to be developed and their clinical performance needs to be demonstrated before deployment at scale can happen.

The successful implementation of serologic testing strategies at large scale can help reduce the spread of the virus and complement the TTT strategy. This will also require major efforts, including: 1) verifying the clinical performance of tests, particularly for rapid serologic tests; 2) preparing procurement and logistics arrangements to scale up production and deployment of the tests, and train and deploy human resources, particularly for diagnostic RT-PCR tests; and 3) providing adequate safeguards to protect civil right and privacy of populations while deploying or apps-enabled tracking strategies.