The Food and Drug Administration is warning healthcare providers and consumers that some thermal imaging systems used to detect body temperature may provide inaccurate results.

Also known as telethermographic systems, infrared thermographs, thermal cameras and “fever cameras,” the devices often are being used to screen for potential fever as part of COVID-19 risk management protocol. Some nursing homes and senior living communities, for example, are using them as part of efforts to triage staff members and vendors for elevated temperatures in an effort to reduce COVID-19 transmission.

But some firms are marketing unapproved, uncleared and unauthorized thermal imaging devices to measure human body temperature, including those that measure multiple individuals’ temperatures simultaneously, the agency reported. It recently issued warning letters to Certify Global, Kogniz, Opgal Optronic Industries and Thermavis.

“While thermal imaging is not an effective diagnostic device for COVID-19, it can determine if someone has an elevated temperature, which can be an important risk management tool during the pandemic when used properly,” said William Maisel, M.D., M.P.H., chief medical officer and director of the Office of Product Evaluation and Quality in FDA’s Center for Devices and Radiological Health. “But improper use and marketing of thermal imaging systems may lead to inaccurate temperature readings and pose a potential danger to public health,” he said in a March 4 statement. 

The recipients of warning letters are listed on the agency’s updated Warning Letters page, and COVID-19-related letters are published on its Fraudulent Coronavirus Disease 2019 Products page.