While it has been joked about and assumed to be the upcoming most popular costume theme for this coming Purim, dressing up as a Corona patient is actually the subject of a halachic dispute.

A posek in Modiin Ilit, Rav Mordechai Schwartzbord, was asked if it is ok to dress up as a sick person, as his daughters kindergarten teacher wants to dress the children in gan up as Chinese people sick with Corona wearing face masks.

Rav Schwartzbord paskened in response that one should not dress up as a sick person, because of the iconcern of "al tiftach peh lsatan" - do not give the Satan an opening, or ideas. Presumably, if you dress up as a sick person, it could lead to you being prone to getting sick.

The question was then sent to Rav Yitzchak Zilbershtein, rav of the Ramat Elchonon neighborhood of Bnei Braq, with the additional question of dressing up as an elderly person who uses a walker or anything similar. Would this entire issue be a problem and if yes, would it be extended to such levels?

Rav Zilbershtein responded that the referenced Mishna (by Rav Schwartzbrod) was referring to somebody who generally makes himself look ill or maimed, and that causes a chilul hashem as it appears that Hashem created many ill or maimed people, whereas if someone were to see more healthy and well people he would praise Hashem for his wonderful creations. SOmeone appearing as a sick person is a kafui tovah and is lessening the praise of God.

That is normally, but on Purim everyone knows it is just a costume and there is no lessening of praise of God or His honor, and therefore it is ok to dress up in the costume of a sick person.
source: Kikar