After a follow-up study of 9 people wearing contact lenses and 11 people who did not wear contact lenses, the researchers found that compared with those without contact lenses, the average number of bacteria on the eyeball of people wearing contact lenses increased by an average of two times. There were also differences in the composition of eyeball surface flora between the two groups. Pseudomonas, a bacterium that causes corneal ulcer, is more common in the eyes of people with contact lenses. It can be seen that changing the flora in the eyes with contact lenses is more likely to lead to eye infection
Sample size of this study is too small, so we should be cautious about the survey results, if true, best supports the above argument.