The drop in oil prices is b/c Saudi Arabia is threatening to flood the world's oil supply, thus putting the Russian oil producers in jeopardy. It is also squeezing small American oil producers and fracking operations. If a drop in demand in China b/c of the virus was causing the drop in price, the Saudis would accomplish nothing by flooding the market. This is all a power play by the Saudis to punish Russia having failed to reach an agreement at OPEC+.
http://www.freerepublic.com/focus/f-news/3823286/posts