Portugal recorded 680 excess deaths across three periods during the summer of 2026, according to estimates released on Thursday by the Instituto Nacional de Saúde Ricardo Jorge. The data was updated to July 30 by the institute and the Direção-Geral da Saúde and provided to the Lusa news agency.
The first period occurred on June 16, when health officials estimated 62 excess deaths, representing a 22.4 percent increase above expected mortality. This initial spike coincided with an episode of elevated temperatures.
The second period was the largest in magnitude and took place between July 2 and July 8, with an estimated 555 excess deaths. That total was 29 percent higher than expected mortality for the period.
Health authorities stated in an assessment requested by Lusa that the second period coincided with an episode of extreme and prolonged heat. They added that high temperatures in the days immediately following the heatwave may also have influenced mortality.
Mortality patterns and affected age groups
The third period occurred on July 23, with an estimated 63 excess deaths, representing a 23.5 percent increase compared to expected figures. Health entities noted that this spike primarily affected people aged 75 and older.
The health agencies cautioned that July 23 was a single day and that recent data may still undergo adjustments as records are updated. They stated that consolidated information will be necessary to evaluate the true significance of the single day increase.
The Instituto Nacional de Saúde Ricardo Jorge and the Direção-Geral da Saúde explained that these estimates measure excess mortality from all causes. The figures were calculated using statistical models that compare observed mortality with expected mortality for this time of year.
The overall pattern showed that the majority of deaths occurred among people aged 75 or older. The primary underlying causes were circulatory, respiratory, and neoplastic diseases.
Health authorities noted that deaths where excessive heat exposure was coded as the basic cause of death represented only a small portion of the total heat impact. In most cases, heat acted as a triggering or aggravating factor for other pathologies rather than the primary cause listed on death certificates.
In contrast, mortality among younger age groups was driven mainly by external causes. Health officials reported that younger age groups did not present a pattern directly linked to high temperatures.
Predictive models and health response measures
The observed mortality figures were lower than the impact predicted by the ÍCARO Index. The ÍCARO Index is a predictive model that assesses health risks associated with observed or forecast temperatures.
Health authorities indicated that the difference between predicted and actual figures could be related to several factors. These include the effectiveness of public health preparation and response measures, actual thermal exposure felt by the population, the temporal displacement of mortality known as harvesting, and the ongoing consolidation of death records.
The agencies explained that the magnitude of impact from each heat episode depends on the intensity and duration of the heatwave. It also depends on the effectiveness of protective measures taken to safeguard vulnerable populations.
In the absence of competing causes such as respiratory viruses, health officials concluded that excess mortality during these periods was mostly attributable to extreme temperatures.
European context and health monitoring
Health authorities noted that the mortality pattern observed in Portugal is similar to patterns recorded during previous heat episodes in Portugal and other European nations. Countries such as Spain and France recorded higher excess mortality figures than Portugal during similar events.
Officials explained that extreme heat frequently acts as a precipitating or aggravating factor for pre-existing conditions, particularly cardiovascular and respiratory illnesses. This increases the risk of acute medical events and death, especially among elderly people, fragile individuals, or patients with multiple comorbidities.
The Direção-Geral da Saúde is maintaining active monitoring of weather conditions, health indicators, and mortality data. This monitoring is conducted in coordination with the Instituto Nacional de Saúde Ricardo Jorge, the Instituto Português do Mar e da Atmosfera, and other health ministry entities.
Health authorities stated that they will adjust measures in the National Plan for Seasonal Health Preparation and Response whenever weather conditions and health data require changes.
