When I started a different insulin pump two years ago, the company could send me only three sensors at a time, each of which lasted a week, because its factory in Puerto Rico had been damaged by Hurricane Maria. Today Beijing is the problem. If insulin or anything related to my pump comes from China, I am in trouble.

But if it hadn’t been Covid-19, it would have been something else. The advent of the internet made it much easier for companies to outsource production to foreign countries where labor costs are lower. Combine this with the popularity of just-in-time production, which minimizes excess inventory, and you have long, vulnerable supply chains. Like many other corporations, large drugmakers have engaged in extensive outsourcing. Though this system may be economically efficient, it is perilous for people whose lives depend on reliable delivery of medical materials. In a crisis, timely deliveries are all the more important, while the supply chain is under all the more strain.

The coronavirus crisis will likely highlight this problem for many, but the issue is more complex than fragile supply chains. Even if drugs and medical supplies are available, patients can’t always accumulate a backup supply because of limitations imposed by insurance companies, pharmacies and government regulators. My provider, for instance, allows prescriptions to be refilled only every 30 days.