Businesses don't want to pay premiums for costs they can cover themselves should the need arrive. I suspect some things required to mitigate a pandemic are expenses the business could reasonably afford, instead of giving an insurer profit.
Similarly, insurers prefer not to insure something that can't be diversified, or the losses can't be reasonably well predicted. Geographic risk is diversifiable because if there is a hurricane that hits SE USA, the rest of the globe is unaffected. With a pandemic, you could be facing 100% of your policyholders with payable losses. This is why business interruption insurance does not cover pandemic losses.
Pandemic mitigation feels more like a service an insurer could provide their customers rather than something an insurer would want to cover directly. For example, an insurer could provide businesses with the resources needed to create business continuity plans in a variety of situations, and one of those situations could be "how to respond to a pandemic".
For a business, having a plan for responding to unforeseen situations is pretty valuable. By purchasing other coverages from an insurer, you could get access to services as I mentioned above.
There could be a market for it, but I don't view it as something businesses will feel they need. It's quite possible that more people will be looking to buy business interruption insurance that covers losses incurred as a result of a pandemic, and pandemic mitigation coverage could be included in that insurance, but I don't think it would be successful standalone.
I wonder if I owned a restaurant if I would be interested - that's who we really need to ask!
Good luck with becoming an actuary! I don't think your question was ignorant at all, seems like a pretty thoughtful question to me. Have you taken any exams yet?