Eighteen people were left blind in Brazil after surgeons used unsterilised instruments during a cataract treatment campaign. The surgeries took place in an industrial suburb of Sao Paulo, where a total of 27 people were treated, officials said on 31 March.

"Everything was fine when I left the hospital on the Saturday I was operated on. All was fine on Sunday. I could see perfectly well," said Expedito Batista. "But when I woke up on Monday, it was all dark. I couldn't see a thing."

According to Sao Bernardo do Campo city hall, 22 people were affected with an eye infection known as endophthalmitis and 18 out of them went blind following the surgery on 30 January. An investigation followed next and revealed that there was contamination during the surgery due to "flaws in the disinfection and sterilisation of the surgical instruments used," according to a Yahoo News report.

The lawyer for the ophthalmology institute which performed the surgeries said he is unable to comment since he is yet to examine the Sao Bernardo's Health Department investigation report. Cataract surgery is performed to treat the clouding of an eye lens by performing a procedure to remove and replace it with an intraocular lens implant.

Less than 10 out of 100 people reportedly suffer complications from the surgery, which include partial or complete blindness. According to a recent study performed on dogs, it is believed that cataracts – which is behind half of the blindness cases worldwide – could soon be cured with eye drops without requiring costly surgeries.