This article will review the signs and effects of the spread of smallpox in colonial Peru, the main cause of which was the arrival of the Spaniards in the New World in the 16th century. This will be done based on the analysis of the story «¡A nadar, peces!», by the renowned writer Ricardo Palma, a text that describes the character Father Carapulcra, in whom the prevalence of smallpox in the Viceroyalty is described. Finally, the relationship between smallpoxand its treatment and the current situation of COVID-19 will be analyzed.