Question: I am a junior at a large state university. Lately, as you all have probably heard, the coronavirus is spreading like a wildfire and we all should be scared.

My instructor is from China, and my school is also filled with Asian students. How do I ask for excused absences so that I can stay at home for the lectures so that I won't get the virus from my instructor or my Asian classmates? Do I contact the chair of the department that's offering the course or the dean of the school? Would it be better if I ask to switch to an online class instead (it's already after the add/drop period)

Some suggestion would be helpful.

Answer: 
If you have a special need, such as an immune deficiency, and must avoid all potential sources of infection, then your university will probably have some procedures to accommodate you. If you have deep psychological fears of disease then your university may have a counseling office to help you deal with your fears. 

Otherwise, the other answers here, counseling you to relax should be considered as good advice. 

Note, of course, that authorities are dealing with the problems of international travel by isolating travelers who might have become infected so that the problem is contained. It isn't Asians you need to be concerned with in any case. It is those frequent international travelers who don't comply with quarantine guidelines.
"We should all be scared" [citation needed]

However, some concern is reasonable. For this reason it is likely that your university has developed policies around this topic. Ask your contact point at the university (e.g. a student service centre or similar). Please be careful to avoid racism against people who look Asian.