The months of July and August 2025 in Portugal experienced significant fluctuations in mortality rates, with new records of exponential jumps observed. According to data from the Death Certificates Information System (SICO), there were 20 consecutive days between July 27 and August 15 marked by excess mortality, amounting to 1,331 deaths. This represents a relative increase of 25% over the period, highlighting a stark rise in health inequalities during this critical climate season.
The high mortality rates are attributed to the increasing intensity of Portugal’s July and August warm weather. General>Description for Health (DGS) reported that excess deaths were uniformly observed across the country, though particularly evident in the northern regions, the central areas, and the southern Alentejo region. The primary cause of these elevated mortality rates was closely linked to heatwaves, which significantly promoted dehydration and exacerbation of chronic diseases, especially cardiovascular and respiratory issues, particularly in vulnerable populations, including the elderly.
Data from the Dr Ricardo Jorge National Health Institute reveals that the majority of the problematic deaths occurred among older adults, underscoring the rising burden of healthcare-associated illnesses (HCACs) in the older population. Notably, deaths among individuals aged over 70 accounted for 80% of all case reports, while the elderly served as the most affected demographic. The DGS emphasized that the oldest-life group, with the highest health surveillance burden and the lowest physiological capacity to cope with heat, was the most vulnerable to the adverse effects of extreme weather events.
Among the 34 days of excess mortality recorded in July and August, 29 days saw higher than expected death rates for the over 70 age group. Furthermore, the shortest-lived expressions of the heatwave, that is, two days of hot temperatures in July (1-9, and 25-31), contributed to the higher case load in those days. The Portuguese Institute for the Sea and Atmosphere (IPMA) marked this month as one of the hottest since 1931, with air temperatures exceeding the monthly average by more than 3°C on multiple significant weekdays.
July itself marked the peak of this exponential increase in mortality, occurring simultaneously with the end of the flu epidemic period. In contrast, January, the previous maximum reported month, also faced heavy heat but was not as severe. The Internationalcampaign against the flu (ICF) reported that it peaked in January 2024, just three months before July 2022, when Portugal experienced one of its coldest and most extreme climate conditions. This stark contrast highlights how weather-related health crises are not mitigated by countermeasures but instead escalate, particularly in vulnerable populations.
While the number of deaths in July and August stays in line with that of the same period in 2024, the surge is particularly stark. Public health officials are devising strategies to reduce exposure to high humidity during this period, as the time frame for severe air pollution is growing. The complications of heatwaves, including the fluidity of blood flow and the increased susceptibility of older adults, remain significant concerns for public health, where the allocation of resources is constrained by the need to address the oldest life in the uneven climate timeline. The ongoing hot weather, combined with the un大规模 contractions of the atmosphere caused by shortened dry spells, poses a critical challenge for public health, requiring targeted interventions to prevent the further exacerbation of mortality in vulnerable populations.
