Our adaptive immune systems can take days to become fully effective, meaning infections can take hold. Researchers are working on being able to put our innate immune systems on 'high alert' to prevent things like influenza and the common cold.

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Our adaptive immune systems can take days to become fully effective, meaning infections can take hold. Researchers are working on being able to put our innate immune systems on 'high alert' to prevent things like influenza and the common cold.