Gloves protect the researcher, not the bat, unless you are using individually wrapped sterile surgical gloves. Whether you are wearing a glove or not makes absolutely no difference when handling multiple bats unless you either change gloves between each bat or wash the gloves with hand sanitizer or spray with alcohol. Cleaning your hands between each bat has exactly the same result.
Wearing gloves can actually lead to a false sense of security- I work in medical research and I see this all the time with new students. They put on gloves then handle all kinds of things in the lab and think because they have gloves on their hands are clean. They will open a bacterial culture fridge door and then go in another room and reach for a bottle of sterile media with the same glove on. They have to be trained to understand that the OUTSIDE of the glove is NOT clean.
With the H1N1 flu epidemic going around The hospital has had a media blitz about the importance of hand hygiene and has really stressed using hand sanitizer (purell is 62% alcohol)
This from the CDC:
The antimicrobial activity of alcohols can be attributed to their ability to denature proteins. Alcohol solutions containing 60%--95% alcohol are most effective, and higher concentrations are less potent because proteins are not denatured easily in the absence of water
Alcohols have excellent in vitro germicidal activity against gram-positive and gram-negative vegetative bacteria, including multidrug-resistant pathogens (e.g., MRSA and VRE), Mycobacterium tuberculosis, and various fungi Certain enveloped (lipophilic) viruses (e.g., herpes simplex virus, human immunodeficiency virus [HIV], influenza virus, respiratory syncytial virus, and vaccinia virus) are susceptible to alcohols when tested in vitro. Hepatitis B virus is an enveloped virus that is somewhat less susceptible but is killed by 60%--70% alcohol; hepatitis C virus also is likely killed by this percentage of alcohol.