The heat wave currently afflicting large parts of Mexico isn’t just uncomfortable for tens of millions of people — for some, it’s also deadly.

Heat-related deaths have been reported in at least three states this week, while hot weather had claimed seven lives across the country by May 4, according to the federal Health Ministry.

In the Huasteca region of San Luis Potosí, 10 people died with symptoms of hyperthermia between Wednesday and Thursday, according to a report by the La Jornada newspaper that cited local Red Cross and Civil Protection sources. Another person reportedly succumbed to a heat-related illness in Ciudad Fernández, located east of San Luis Potosí city.

The Husateca region of San Luis Potosí has recorded extremely high temperatures this week. La Jornada reported that Tamuín, the municipality where six of the deaths occurred, reached 52 C on Thursday. That appeared to be a reference to the apparent, or “feels like,” temperature, known in Spanish as sensación térmica.

In Veracruz, one person succumbed to a heat-related illness last weekend, according to a report by Diario de Xalapa. The newspaper said that a truck driver passed away in the municipality of San Juan Evangelista after showing signs of dehydration. “He received support from paramedics but didn’t manage to survive,” Diario de Xalapa said.

The newspaper also reported heat-related deaths in Papantla on May 3, the day the current heat wave began, and Minatitlán last month. Neither of those deaths were included in the Health Ministry’s latest “extreme natural temperatures” report, although they occurred before the May 4 cutoff date.

In the neighboring state of Oaxaca, an 8-year-old boy died of apparent heatstroke, according to health official Ignacio Zárate Blas. He said that the boy from the Papaloapan region of the state arrived at hospital with symptoms of dehydration and that it is believed that he died of heatstroke. However, Zárate noted that the boy was also suffering from “some accompanying ailments.”

Oaxaca Health Minister Alma Lilia Velasco Hernández reported on Monday that two young men — one aged 18, the other 25 — had died of severe dehydration. Both were treated in hospital but were unable to recover. The 18-year-old was from the Isthmus of Tehuantepec region, while the older man was from the Costa region of Oaxaca and worked as a street vendor.

Parts of Oaxaca have recorded temperatures in excess of 40 C this week.

Health Ministry: 7 heat-related deaths before May 4

In a report published Thursday, the Health Ministry said that a total of 337 cases of heat-related illnesses and seven deaths were recorded between the March 17 commencement of “the present hot season” and May 4.

Tabasco recorded the highest number of heat-related deaths with four, while there were two fatalities in Oaxaca and one in Chiapas. The deaths were all attributed to heatstroke.

Two of the four deaths in Tabasco occurred in early May, both in the municipality of Huimanguillo, which borders Veracruz and Chiapas.

It was unclear why the heat-related deaths in Veracruz in April and on May 3 were not included in the latest report. They — and the deaths reported this week — may show up in next week’s report if state authorities convey the information to their federal counterparts.

The heat-related illnesses reported by the Health Ministry included cases of heatstroke, dehydration and sunburn. Heatstroke accounted for almost two-thirds of the cases while most of the remainder were cases of dehydration.

There were more heat-related deaths, and more cases of heat-related illnesses this year than at the same time in the previous four years. By early May last year, there had been three heat-related deaths and 267 cases of illness.

However, the heat-related death toll subsequently soared to reach a total of 421 in 2023, a figure 10 times that of 2022.

This year’s “hot season” will conclude Oct. 5, according to the Health Ministry.

With reports from Diario de Xalapa, La Jornada, Milenio, El Heraldo de Tabasco and Proceso