Do face masks prevent endophthalmitis infection during anti-VEGF injections?

Use of face masks by both patient and physician during intravitreal antivascular endothelial growth factor (anti-VEGF) injections does not modify the risk of presumed acute-onset bacterial endophthalmitis, but a reduced rate of culture-positive endophthalmitis is noted, reveals a study.

“Routine use of face masks for patients and physicians during intravitreal anti-VEGF injections has increased with the emergence of the coronavirus disease 2019 pandemic,” the authors said.

This retrospective, multicentre, comparative cohort study analysed a total of 110,547 eyes receiving intravitreal anti-VEGF injections from 1 October 2019 to 31 July 2020 at 12 centres. The authors divided the cases into a “no face mask” or a “universal face mask” group.

Overall, 505,968 intravitreal injections were administered. Eighty-five out of 294,514 (0.0289 percent; one in 3,464 injections) cases of presumed endophthalmitis occurred in the “no face mask” group and 45 out of 211,454 (0.0213 percent; one in 4,699) in the “universal face mask” group (odds ratio [OR], 0.74, 95 percent confidence interval [CI], 0.51–1.18; p=0.097).

Twenty-seven cases (0.0092 percent; one in 10,908 injections) of culture-positive endophthalmitis occurred in the “no face mask” group compared with nine (0.004 percent; one in 23,494) in the “universal face mask” group (OR, 0.46, 95 percent CI, 0.22–0.99; p=0.041).

In addition, three cases of oral flora-associated endophthalmitis occurred in the “no face mask” group (0.001 percent; one in 98,171 injections) relative to just one (0.0005 percent; one in 211,454) in the “universal face mask” group (p=0.645).

After the causative injection, patients presented a mean of 4.9 days (range, 1–30), and the mean logarithm of the minimum angle of resolution (logMAR) visual acuity (VA) at endophthalmitis presentation was 2.04 for the “no face mask” group and 1.65 for the “universal face mask” group (p=0.022). There was no between-group difference in VA seen 3 months after treatment (p=0.764).