Abstract
Cyprinid herpesvirus 3 (CyHV-3), the causativeagent of koi herpesvirus disease, is a major threatfor carp populations in many countries worldwide,including Indonesia. It has been shown that manygenotypes circulate worldwide, all highly relatedto one of the two known lineages U/I and J. Inthis study, we evaluated the spatial and temporaldistribution of CyHV-3 strains in a small enzooticarea, the lake of Cirata (West Java, Indonesia). Ofthe 365 samples analysed, from clinical or asymptomaticfish, 244 were found positive for CyHV-3, suggesting a high occurrence of the virus.Genotyping of these viral specimens with a rangeof molecular markers revealed the presence ofnumerous haplotypes in the host population, allrelated to the J lineage. In single individuals,mixed-genotype infections occurred at high frequency.The present results demonstrate thatpolymorphic molecular markers are suitable tomonitor the genetic evolution of a viral populationin an enzootic area.