Great North American eclipse 2024 and ocular complications in Quebec, Canada : results from a population-wide surveillance

Abstract

Purpose On 8 April 2024, a total solar eclipse was visible to 40 million people in North America, including most of the 8.5 million in the Canadian province of Quebec. The Ministry of health, the Order of optometrists of Quebec and the University of Montreal organized a province-wide surveillance to document the frequency, severity and risk factors of ocular complications. Results of this surveillance are described here. Methods The surveillance had three components. First, it monitored the number of eclipse-related calls to Info-santé, a hotline for minor health emergencies. Second, it compared the weekly incidence of emergency room consultations for ocular lesions, to that of the same weeks in previous years. Third, for four weeks after the eclipse, a reporting form was made available to the 1400 optometrists throughout Quebec. It collected data on ocular complications: symptoms, behaviour during observation, visual acuity and ocular coherence tomography (OCT). Results Eclipse totality occurred around 15:25, in clear skies. Between 8 – 13 April, Info-santé received 33 eclipse-related calls, including 17 on 8 April. In the following week, incidence of emergency room consultations for ocular lesions increased to 2.5/100 000 person-weeks, compared to 1.8/100 000 person-weeks in reference years (p < 0.05). There were 46 reports of ocular complications: 35 solar keratitis and 11 solar retinopathies. Age ranged from 13 – 64, mostly above 18 years. Five cases (n = 5/46, 10.8%) had reduced visual acuity, from 6/7.5 to 6/9. Most cases of retinopathy had abnormal OCT (n = 7/11, 63.6%). Risk factors included inadequate protection (n = 22/46, 47.8%) and false sense of security (n = 14/46, 30.4%). Conclusion Notwithstanding the large public exposure to this eclipse, its impact on the population eye health in Quebec was limited, with a small number of low-morbidity ocular complications.