‘Can you treat a KHV infection?’, ‘Can human be infected with KHV?’ and ‘Can my cat transfer KHV from my Koi pond to the pond of the neighbors?’. For many people there are a lot of questions about this virus. I would like to discuss these and other questions regarding the Koi Herpes Virus with you. However, we then need to know what we are talking about and what KHV is. We will start with a general introduction on viruses, where I explain what viruses are.