When we think of the spread of antibiotic resistance between animals and humans, we tend to think of it going from Them to Us. For example, much of the research over the past 20 years on the sub-clinical use of antibiotics in animal feed has looked how this use of antibiotics as a growth promotant breeds resistant organisms in animals, which can then enter the human population via the food we eat. Along a similar line, I just mentioned Burt’s post post on cephalosporin use in cattle and the evolution of antibiotic resistance, where the worry is that use of these broad-spectrum antibiotics in animals will select for resistance that can then spread to humans. However, spread of resistant organisms is not a one-way street. For example, it has been suggested that transmission of methicillin-resistant Staphylococcus aureus (MRSA) has been transmitted both from horses to humans and vice-versa (see, for example, this Emerging Infectious Diseases paper). A new paper suggests that this phenomenon can happen even in animals that aren’t in such close contact with humans: chimpanzees.

(Continued at Aetiology)