What happened and when?

On Feb. 21, hackers accessed an IT system at a subsidiary of UnitedHealth Group, which is based in Minnetonka. This prompted the company to suspend operations of the electronic data clearinghouse and related systems at its Change Healthcare business. These systems are used widely by pharmacies, hospitals and clinics. Change processed an estimated 50% of of all U.S. medical claims in recent years.

How are health care providers affected?

Immediately after the hack, drugstores could not verify coverage for medications at the pharmacy counter, although UnitedHealth Group says these systems now have been fully restored. Hospitals and clinics have been unable to file claims for payment from insurance companies, raising worries for how they will financially maintain their businesses.

Do we know who did it and what their motive was?

The company says cybercrime threat actors gained access to certain information technology systems at Change Healthcare, and the actor represented itself as ALPHV/Blackcat. This group is notorious for encrypting data to hold it hostage in order to secure massive ransoms via cryptocurrency. UnitedHealth says all other company systems are operational.

I have a UnitedHealth insurance plan or Medicare Advantage plan. What does this mean for me?

This affects many health insurers — not just United — because Change's systems are used throughout the health care system. In all cases, there shouldn't be a disruption in the care you receive. Hospitals and clinics might not be able to say right now what you owe in deductibles. And there are longer-term concerns about patients receiving late and/or erroneous bills as the mess gets sorted. Risks from stolen data are unclear.