Ask HN: How is an 18-month period of paused economy realist?

I've read the Imperial College report[1] that is presumably the reason of the UK and the US change of strategy.

It mentions that we're heading towards 12-18months of lockdown alternating between suppression and mitigation, with 2/3rd of the time spent in suppression (current situation where schools, restaurants, etc. are closed).

How can any economy survive this?

In addition, how are loans going to help these businesses who are going to have zero source of revenue for the next 12-18 months?

[1]: https://www.imperial.ac.uk/media/imperial-college/medicine/sph/ide/gida-fellowships/Imperial-College-COVID19-NPI-modelling-16-03-2020.pdf