I was personally frustrated at WHOs apparent great fear in moving from classifying from epidemic to pandemic, all the more so given all the evidence we had gathered from Chinas experience, historically, a great strength of the WHO was its expertise in consensus building. Here, we neededleadership, not merely consensus building. It is hard for some organizations to act.

Stanley Weiss

We expect that at some time it will help diminish the spread of COVID-19, based on the assumptions that persons who are infected and recover will have protective immunity, however, with SARS, data suggested protective immunity was of limited duration. Thus, the precise temporal dynamics may prove very important. For example, there could be recurrent waves. We hope with COVID-19, but do not yet know that they wont become re-infected.