(a) Seasonal abundance of CyHV-3 in gill and brain tissues of common carp: +, CyHV-3 concentrations in gill tissues of fish captured in 2008; × , those in brain tissues in 2008; ○, those in gill tissues in 2009; □, those in brain tissues in 2009. Water temperature changes in 2008 and 2009 are indicated by dashed and solid lines, respectively. (b) CyHV-3 concentrations in intestinal contents of common carp captured in 2009. Solid line indicates water temperature.