Injected conjunctiva (redness) of the right and left eye (top row). Diffuse staining of the cornea with green dye indicating epithelial damage (bottom row)

US clinics have reported encountering patients who developed photokeratitis after exposure to ultraviolet (UV) germicidal lamps while attempting to eliminate coronavirus from homes and offices.  

“During the height of the pandemic, we noticed an increased number of patients coming in with irritation, pain and sensitivity to light,” said lead author Dr Jesse Sengillo, Bascom Palmer Eye Institute at the University of Miami Miller School of Medicine. “We realised this was after direct exposure to germicidal lamps that emit UV light in the C range to kill bacteria and viruses. This can be quite a painful experience for the patient, but with prompt topical lubrication and antibiotics to prevent infection, patients often do very well.” 

Photokeratitis occurs when the cornea is overexposed to UV radiation. This can happen at high elevation, where fewer UV rays are absorbed by the atmosphere, or near water, snow or other reflective surfaces in the environment. A few hours after exposure, patients experience a burning sensation in their eyes and sometimes intense photophobia. 

While UV lamps may be safe for at-home use, users need to pay close attention to manufacturer recommendations to prevent damage to the eyes and skin, authors wrote, adding that with UV-C-emitting devices, it’s best to leave the room while the device is on. Although such devices are proven to be effective in killing various microbes and viruses, the authors noted that, to their knowledge, they have not been tested against Covid-19. 

The study was published by Ocular Immunology and Inflammation.