'Good' Bacteria Lacking in City Homes

The researchers found that homes in urban areas in South America tended to have lower levels of certain microbes commonly found in the environment, compared with homes in rural areas. However, homes in urban areas had higher levels of microbes associated with human presence, which could potentially mean an increase in the transmission of the bacteria that cause disease, the researchers said. For now, the researchers don't know with certainty whether the differences in bacterial composition found