Just as when money is created for the central bank to use to purchase newly issued debt of the central government, at some point in QE money is created, however it is treated as a matter of bookkeeping: adding 'liquidity' to the financial system is the whole point.

The ways and means of securing any possible additional funding for government are TBD, but at least we would be starting at zero. It is tempting to suggest that emergency funding such as the present case could be funded by simply increasing the funding available for government, but it is easy to foresee the abuse of what constitutes an "emergency." One must also keep in mind, however, that current government spending includes welfare of various kinds that would no longer be needed.