If the drop in the stock market is based off fears of the corona virus, then buy. If you die from the virus what difference does it make. But, if, as I predict, this is just another way for the big boys to create fear you should do fine. Just buy and hold.
The bigger issue, in my opinion, is that fear always seems to surround election years. I deal in real estate and in the past you could see the slow down as the election came around, then take off again when whoever won, didn't really matter who.

People hate uncertainty, but it is truly when the rich take off. I lost a ton in 2008 and my income just about disappeared, so I was in no position to buy. I had friends who were heavily invested in stocks during the boom and were trying to buy some real estate. I told them to wait. Some went and bought anyways, and lost fairly large. When the recession hit, I could not get any of them to buy. I had one property in particular that was selling for $38,000 and needed about $3000 to $5000 in repairs. I had no cash so I couldn't grab it. Rent on the unit was around $950. Expenses would have dropped it to around a $650 to $700 return. Rents now are probably about $1600. At the lower rate the return would have been in the 18% range. A similar unit just sold for around $225,000. I got some one to finally buy it but they too got scared and flipped for around an $8000 profit. There were several others similar homes in the area but no one would touch them, as real estate was too scary-- despite the built in 18% return that was already there.
Lesson --- buy when others are scared. Or as Buffet says "Whether we’re talking about socks or stocks, I like buying quality merchandise when it is marked down"