Appendix Figure 1. Visual inspection of the positivity of LAMPreactions. Heated, treated viral culture was serially diluted and tested by the LAMP assay. Reactions were visually inspected after the incubation. Positive reactions would produce large amounts of white magnesium pyrophosphate precipitate, thereby increasing the turbidity of these reactions (+ve control and samples 1 to 3). By contrast, negative reactions (-ve control and sample 4) remained transparent after the incubation. The amount of pfu used in the tested samples is indicated.