Take the airlock out. There will be a blanket of CO2 on the beer and any air pulled in will be lighter than the CO2, so the chances of contamination are very small.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk