If there's a complete cure for covid 19 in the mere future, the economy will soon rise again because right now due to pandemic the production rate of all products has been reduced that lead to lack of supply that cause a huge drop on our economy, and if the restrictions(social distancing, quarantine, lockdown and etc..) have been lifted the shortage of production rate will again increased due to increased in man power.
As for the banks I think they won't face any problem on that because they can easily change Fiat to digital or vise versa due to the help of the government and the society itself.
I think that we should not hope for a complete cure from covid-19 in the near future, because this is a question of mass vaccination, and this is purely organizational and technically difficult to solve in the next few months on a large scale, it also depends on the conditions in the state itself, how the population is distributed, whether the state has the necessary funds to create and support infrastructure for storing and distributing vaccine doses that require very low temperatures.
The distribution of vaccine may take time, but I am sure it will reach to every person needed. WHO would have already co-ordinated with each country by now or in process once the vaccine is finalized and the further steps so that it reaches as soon as possible and needy be given on priority. Again, it depends which country gets it first and how much production can be done on daily basis as to cover whole population is a massive thing.