There is a good deal of discussion about whether insurance will cover some of the substantial costs associated with the Covid virus.
1. Policy Terms 
The first question will be what does the policy provide, and indeed, there are a range of policies.
2. Direct Physical Loss of Damage Requirement
Many policies require proof of “direct physical loss or damage.”
3. Other Cases
One court found that bacterial and mold contamination was not a “direct
physical loss” under a property insurance policy. Universal Image Products. v. Federal Insurance Co., 475 Fed. Appx. 569 (6th Cir. 2012). However, Gregory Packaging, Inc. v. Travelers Ins. (D.N.J. 2014), found such a loss from an ammonia leak in a building. See Businesses Scramble to Assess Insurance Coverage for COVID-19.
However, it would be hard to attribute a general downturn, or instruction to stop work as a incident of physical loss or damage.
4. Exclusions
Some insurers inserted exclusions of viruses in their policies.