Nature Reviews Immunology 11, 143–154 (2011)

In Figure 3 of the original version of this article, viral RNA was shown to interact with TLR9 and viral DNA was shown to interact with TLR3. This is incorrect and instead viral RNA interacts with TLR3 and viral DNA interacts with TLR9. This has now been corrected online. Nature Reviews Immunology apologizes for this error.