Reply to Kjartansdóttir et al.: Chlorovirus ATCV-1 findings not explained by contamination

We agree with Kjartansdottir et al. (1) that extreme caution must be used when interpreting high-throughput sequencing results in new hosts. The situation demands thorough investigation and validation beyond the identification of a few sequencing reads. However, we believe it is unlikely that random laboratory contamination explains the results reported in Yolken et al. (2) for the following reasons.