Eyeworld

76 | EYEWORLD | SEPTEMBER 2021 C ORNEA Contact Aldave: aldave@jsei.ucla.edu Khandelwal: Sumitra.Khandelwal@bcm.edu Mian: smian@med.umich.edu One argument for universal testing was data showing how long the infection lasts post- mortem, which could help with a guideline for collecting samples. The EBAA does not require eye banks to perform donor RT-PCR testing for SARS-CoV-2, but other organizations around the world are. Still others advise against it. Dr. Aldave noted that results on postmortem donors could take up to several days, which could delay tissue placement and processing, and universal testing could also increase costs. Although Dr. Aldave and colleagues have reported eight cases of corneal transplantation using tissue from donors who tested positive for SARS-CoV-2, only one of the recipients developed COVID-19, which was attributed to a community-acquired infection. 2 These cases highlight the importance of eye banks establish- ing a protocol to ensure timely communication with testing agencies about testing notification and results. COVID-19 has been found in the tear film, and the presence of SARS-CoV-2 viral entry fac- tors have been noted on the ocular surface and in the cornea. Studies have found that it can infect cells in vitro, it remains viable for several days, and it can be found in postmortem tissue. The current EBAA medical standard re- quires double exposure of povidone-iodine to the ocular surface before tissue recovery. This is thought to help inactivate infectious virus found on the ocular surface, but it is not known if the virus in deeper tissues remain. Overall supply of donor tissue Dr. Mian said that some areas, particularly outside the U.S., are starting to feel the impacts of these more stringent screening guidelines for corneal tissue. Initially, there wasn't much of an issue, he said. Through June 2020, the demand was fair- ly low, as most elective surgeries were canceled, hospitals shut down except for emergency care, and a lot of patients were scared to have sur- gery, Dr. Mian said. "Although supply decreased, it was still adequate enough to provide care for anyone who needed care through that time." Since then, demand has increased as better safety protocols were implemented, he said. "Of course, it's hard to not provide care for such an extended time period because people who are suffering and not seeing well need their care." prep, so COVID-19 on the tissue is likely killed," she said. "However, once again, the recommen- dation is not to recover COVID-19 positive or COVID-19 suspects, adding a layer of safety for recipients but also for our recovery technicians." Evolving recommendations from the EBAA Dr. Aldave is chair of the EBAA Medical Ad- visory Board (MAB) Subcommittee that has developed guidelines for eye banks to determine donor eligibility during the pandemic to help ensure the safety of corneal tissues. The EBAA MAB released their initial guide- lines on February 3, 2020. Updated guidelines included a decision table that used the result of reverse transcriptase-polymerase chain reaction (RT-PCR) testing as primary determination of eligibility for ocular tissue donation. Guidelines were further revised with input from eye bank technicians, eye bank medical directors, and others to allow for medical director review for eligibility in the presence of signs and/or symp- toms of COVID-19, the existence of a plausible alternative etiology for signs and symptoms, and the absence of close contact with an infected individual. The FDA updated guidelines on Jan. 4, 2021, to say they don't recommend testing on asymptomatic potential donors, but the donor should be tested if they had specific risk factors. A recent publication by the EBAA MAB Subcommittee chaired by Dr. Aldave noted that COVID-19 has been a strain on the eye bank- ing system around the world, but screening demands are also a huge burden. 2 Testing has been an ongoing issue, whether it's required or not. Early on, testing was not readily avail- able, and some considered postmortem testing of tissue donors an irresponsible use of these limited testing capacity at the time, he noted. Testing still needs to be approached with cau- tion because there are challenges in interpreting results. Some results are inconclusive, Dr. Aldave noted, and these donors could not be used because repeat testing isn't possible. The false positive rate with RT-PCR is relatively low, but donor tissue could be wasted because those who have been infected with COVID-19 may still test positive even though they are not shedding rep- licating virus. This wasted tissue could impact international supply. continued from page 74 References 1. Sawant OB, et al. Prevalence of SARS-CoV-2 in human post-mor- tem ocular tissues. Ocul Surf. 2021;19:322–329. 2. Aldave AJ, et al. COVID and the cornea: From controversies to consensus: Report of the Eye Bank Association of America Medical Advisory Board Policy and Position Review Subcommit- tee. Cornea. 2021;40:809–816. Relevant disclosures Aldave: None Khandelwal: None Mian: None

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