[Massive poisoning with carbon monoxide: an update from a case].

Carbon monoxide is known as the "silent murderer" because it is a colorless and odorless gas. According to these characteristics, toxicity goes unnoticed which makes the diagnosis difficult. In most cases, the cold periods and group poisoning make suspect its presence because inappropriate heat both in home or public environments. Our goal is to inform about a mass carbon monoxide poisoning in a children's parties room using a combustion source installed, not for the purpose of heating, but as a supply of light (generator), emphasizing that it can occur in any time of the year.