A cybersecurity breach on a branch of United Healthcare has affected pharmacies nationwide since last week, causing some pharmacies to experience prescription delays and various health care interruptions.

The cyberattack, according to CBS, targeted Change Healthcare, a Tennessee-based health-tech company that is part of the service provider Optum and is owned by the conglomerate UnitedHealth Group.

Initially, the breach was reported last Wednesday due to issues with the health care company’s connection between insurance claims and prescription filings.

As mentioned in the company’s regulatory finding published last Thursday, it claimed thousands of pharmacies across the U.S. have had their systems compromised by hackers. Specifically, the breach has affected “all military pharmacies worldwide and some retail pharmacies nationally,” per Fox Business.

Examples of pharmacies affected by the cyberattack

CBS reported that “a small percentage” of Walgreens pharmacies may have been affected by the breach, but nothing too significant has been found.

“For the small percentage that may be affected, we have procedures in place so that we can continue to process and fill these prescriptions with minimal delay or interruption,” a Walgreens spokesperson told CBS.

Discount-focused pharmaceutical company GoodRx, however, reportedly had challenges with the breach, stating in its X post:

“We apologize for any outages you have been experiencing while at the pharmacy. Unfortunately, the issue is an external one impacting both GoodRx and a multitude of providers. Our team is aware of the issue and working to ensure it is resolved.”

Regarding military units, Naval Hospital at Camp Pendleton — a California pharmacy strictly for the U.S. Marine Corps — stated in a post to X that it was “unable to process any prescription claims,” only being able to help “emergency and urgent prescriptions from hospital providers” at the time.

What Change Healthcare and others have stated or changed

Optum has continued to share updates of its investigation in a statement, claiming Monday morning that its “experts are working to address the matter.” And when the source of the cyberattack is found, it will take “immediate action to disconnect Change Healthcare’s systems to prevent further impact.”

The American Hospital Association, amid the breach, advised hospital units to disconnect from Optum and examine security systems for any vulnerabilities regarding system processes, per The Wall Street Journal.

Similarly, CVS has implemented safeguarding procedures to not process insurance claims in “certain cases,” although the chain shared there’s been “no indication that CVS Health’s systems have been compromised,” reported Fox Business.

Tricare, the U.S. health care program for military personnel, mentioned that its pharmacies are currently prioritizing “urgent prescriptions” over routine kinds, adding that every clinic and hospital are operating “based on their local manning and resources,” according to Fox Business.

Per CNN, UnitedHealth, in its filing with the Securities and Exchange Commissions, claimed the breach could’ve been sponsored by foreign hackers.

“UnitedHealth Group identified a suspected nation-state associated cyber security threat actor had gained access to some of the Change Healthcare information technology systems,” said UnitedHealth to CNN.

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