Gloves are personal protective equipment(PPE) in addition to safety glasses and hearing protection. They are preventive measures against pathogens. Look in in safety section of your SOP. Cleaning with alcohol is sufficient. Passengers will pick up more germs from doors,railings and and other things than what you could pass onto there stuff. They will be in a sealed metal tube with re-circulated germ infested air for who knows how long so changing gloves is not really an issue.