An epizootic was induced by introduction of Leucoma salicis nucleopolyhedrovirus (LesaMNPV) into satin moth (L. salicis) population feeding on poplar Populus nigra L. Introduction of LesaMNPV virus at a rate 4 x 102 of inclusion bodies per tree into insect population (stage L3 and L4) resulted in a rapid outbreak collapse both in the peak and early decline phases. A rate of epizootic development depended on healthiness of satin moth larvae before the treatment. Insect population with a high level of nucleopolyhedrovirus (app. 21% and 26% infected insects) reached the epizootic peak on the 18th day after the treatment (85% and 86% infected insects). Induced epizootic resulted in the decline phase of L. salicis population that continued for subsequent 6 years. Accidental occurrence of fungus Beauveria bassiana (Bals.) Vuill. extended the population decline phase for the period of at least 8 years. Induced epizootic caused a rapid collapse of satin moth outbreak with direct transition from the population peak phase into the population collapse phase with omission of the decline phase. This pattern was not observed in not treated populations. Artificially induced epizootics affected healthiness of insect pupae and adults as well the reproductive potential of females and healthiness of offspring. The weight of pupae obtained from treated larvae was lower when compared with the control. Virus infections were found more frequently in female pupae than in male pupae. This resulted in a 6–28 fold decrease of the number of egg masses and 3.5–5 times lower numbers of eggs deposited by females. Offspring of infected pairs showed symptoms of viral infection (15–28% infected larvae) and the number of offspring was 70–800 times lower in comparison with offspring of not infected pairs. This study presents the results of induced epizootic and has been the first attempt to review and sum up results of long-term research on evaluation of nucleopolyhedrovirus efficacy in natural conditions.