Following the publication of this article, it has been brought to our attention that several of the authors and the Academic Editor, Dr Syed, were affiliated at the same institution, Aga Khan University, when the peer review process took place.

In line with the PLoS ONE competing interests policy (http://www.plosone.org/st...), we consider this as a potential conflict of interest. Dr Syed was invited by PLoS ONE to act as Academic Editor for this manuscript, and we acknowledge that the journal should not have approached him to handle this manuscript. We have therefore asked an independent Academic Editor James Scott to carefully evaluate the peer review process of this article. Dr Scott has confirmed that he is satisfied that the peer review process and the decision for publication are adequate.

We are therefore content that the review process was handled correctly by Dr Syed.