If immunity to convid-19 is not life after recovery it will come back.  There are now reported two strains and the question is how fast it will mutate into more.  If farm animals get it (pig, chickens) it will have big population (more mutations per unit time).   A low estimate of the death rate say 1% this year if comes back for 10 years that means near 10%.   It is said to resemble HIV and MERS in the way it attaches to cells.  There are no vaccines for either after a few decades.   Treatment for HIV took year to develop and MERS still has none.

Outside China the wold is acting to slow to contain it.  So unless immunity lasts a very long time and it does not develop new strains to overcome that, it will be around for a decade the the human cost will be 10 times that of a one year estimate.