Carbon monoxide (CO) poisoning is a significant public health event. As an odorless, colorless, tasteless, and non-irritating gas produced by the incomplete combustion of materials used for heating or cooking, it becomes an agent of inadvertent exposure with a high associated risk of mortality. In our country, most CO poisonings are caused by improper use, lack of maintenance, or defects in heating or cooking appliances that use natural gas, kerosene, coal, wood, or liquid fuels. As of the tenth week of 2026, 130 cases have been reported nationwide, showing a slight increase compared to the same period in previous years. According to a report from the National Epidemiological Bulletin (BEN) accessed by the National News Agency (NA), this increase is driven by the Province of Buenos Aires (PBA), which has reported 59 cases so far this year, whereas the provincial annual average for 2022-2025 was 14. A similar situation is occurring in the Autonomous City of Buenos Aires (CABA), whose average for the 2022-2025 period was 3 cases, and 21 have been reported in 2026. Conversely, in the Southern region, which had the highest number of cases in previous years, only 13 cases have been confirmed so far in 2026, four times less than in 2025. At the national level, an upward trend has been observed since 2022, increasing from 2.77 cases per 100,000 inhabitants in that year to 4.2 in 2025. While CO poisoning cases show a constant notification throughout the year, a sustained seasonal increase is registered between the months of April and September. In week 27 of 2025 (June 29 to July 5, 2025), a peak of 487 confirmed cases was reported, which is 1.8 times the maximum observed in week 28 of 2024, in which 266 such events were notified. 70% of the cases were concentrated in five jurisdictions: Buenos Aires (140 cases), Tucumán (51), Neuquén (50), Salta (49), and Mendoza (45). The peak coincided temporally with an abrupt drop in temperature, as during that week, the lowest minimum temperatures of the entire analyzed series were recorded in the meteorological stations of the most affected provinces. In Neuquén, the minimum temperature reached -11°C (13°C below average), while in Mendoza it reached -6.7°C, in Salta it was -5.3°C, and in La Plata it was -5.2°C, 10°C below its usual average.
