How urgent do intravitreal anti-VEGF injections need to be to justify the risk of transmitting COVID-19? Proof-of-concept calculations to determine the Health Adjusted Life-Year (HALY) trade-off

ABSTRACT Background Clinical ophthalmological guidelines encourage the assessment of potential benefits and harms when deciding whether to perform elective ophthalmology procedures during the COVID-19 pandemic, in order to minimize the risk of disease transmission. Method We performed probability calculations to estimate COVID-19 infection status and likelihood of disease transmission among neovascular age-related macular degeneration patients and health care workers during anti-VEGF procedures, at various community prevalence levels of COVID-19. We then applied the expected burden of COVID-19 illness and death expressed through health-adjusted life-years (HALYs) lost. We compared these results to the expected disease burden of severe visual impairment if sight protecting anti-VEGF injections were not performed. Results Our calculations suggest a wide range of contexts where the benefits of treatment to prevent progression to severe visual impairment or blindness are greater than the expected harms to the patient and immediate health care team due to COVID-19. For example, with appropriate protective equipment the benefits of treatment outweigh harms when the chance of progression to severe visual impairment is >0.044% for all scenarios where COVID-19 prevalence was one per thousand, even when the attack rate in the clinical setting is very high (5-43%). Conclusion Unless COVID-19 prevalence is very high, the reduced disease burden from avoiding visual impairment outweighs the expected HALYs lost from COVID-19 transmission. This finding is driven by the fact that HALYs lost when someone suffers severe visual impairment for 5 years are equivalent to nearly 400 moderate cases of infectious disease lasting 2 weeks each.