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Pneumonia kills more children under 5 years of age than any other infectious disease, but affordable and effective treatment and prevention measures are available. The time has come for the world to wake up to this forgotten killer.
The increase in allergic diseases that has occurred in developing countries in recent years has been attributed to a decrease in exposure to the microorganisms in the environment. Blaser and Falkow reflect that this increase, as well as the ongoing obesity epidemic and increased susceptibility to infectious disease, might instead be the result of changes in the human microbiota.
Efforts to monitor the range of infectious diseases that affect international travellers and the factors that determine infection rates will provide an evidence base from which more effective preventative measures can be developed. Torresi and Leder review the main findings of one such effort, the GeoSentinel surveillance network.