Forget about the sickness for a second and simply concentrate on the economic impact of the countermeasures. Various economists are projecting the impact of the epidemic on the Chinese economy from 5 to 8% of GDP.
Best case scenario (and we are past that stage) is no other country does anything else and we are left with China alone. China is 20ish percent of the global GDP, so we are talking about 1% to 1.5% reduction in global growth. This is super-optimistic, assumes no knock-on effects etc and it pulls the global growth down 50%. With knock-on effects like the disruption of the supply chains, reduction in travel etc., we are probably talking about a mild global recession. Worst case scenario is that every country is forced to take countermeasures, we have wide economic disruption and are dealing with a global recession of 5%+. Even the best case scenario deserves the markets taking 15-20% hit as they have done historically. Worst case scenario would probably effect the markets in a way similar to the GFC.
If the high school diploma from Bronx Science is the proudest achievement of your career, you must be doing something wrong.