The count of epidemic outbreaks in the Community of Madrid increased by 4.5% in 2025, reaching 442 episodes. Those of acute gastroenteritis (AGE) of non-food origin predominated, and the impact of the flu became particularly relevant, which practically sextupled the linked cases and multiplied hospitalizations by six compared to the previous year.
Despite the rise in the number of outbreaks, associated cases decreased by 28.4%, remaining at 7,196, according to the latest data from the General Directorate of Public Health, released by Europa Press.
During the last year, there were 574 hospital admissions, representing an increase of 149.6% compared to 2024. Additionally, 26 deaths related to these episodes were reported.
With these figures, the annual global incidence stands at 6.21 outbreaks per 100,000 inhabitants, with a rate of 101.15 associated cases per 100,000 inhabitants and a hospitalization proportion of 8% of the total affected.
The outbreaks linked to food establishments, institutions, or groups totaled 362, 81.9% of the total, a percentage very similar to that of the previous year. In parallel, family or private environment outbreaks grew by 48.1%, reaching 80 episodes.
In these family outbreaks, both cases and admissions increased (17.4% and 75.4%, respectively). In collective outbreaks, associated cases decreased from 9,885 in 2024 to 6,994 in 2025 (-29.2%), while hospitalizations skyrocketed from 161 to 453, representing an increase of 181.4%.
Outbreaks of non-foodborne acute gastroenteritis
The outbreaks of acute gastroenteritis of non-food origin topped the statistics with 121 episodes, 27.4% of the total, although with a decrease of 20.4% compared to the previous year (31 less), according to data collected by Europa Press. The incidence was 1.70 per 100,000 inhabitants.
In total, they generated 4,080 associated cases, 40.7% less than in 2024 (-2,795), which represents 56.7% of the total affected. There were 49 admissions recorded, three more than the previous year, with a hospitalization rate of 1.2% of the cases. Additionally, two deaths were reported in nursing homes, "one due to bronchoaspiration in a bedridden person with high dependency and another due to exacerbation of underlying processes."
By type of collective, residences and centers for elderly people concentrated the majority of these outbreaks, with 103, 85.1% of the total. They also accumulated the highest volume of cases, 3,852 (94.4%), and hospitalizations, with 40 admissions (81.6%).
However, it was precisely these centers that reduced their number of outbreaks the most compared to 2024, with a decrease of 22.6% (30 less) and a drop of 40.3% in associated cases (-2,603).
77.7% of these outbreaks occurred in the autumn and winter months. Regarding the etiological agent (virus, bacteria, fungus, parasite, prion), viruses were the most common causes, especially norovirus, responsible for 90.2% of outbreaks with microbiological confirmation and 45.5% of the total outbreaks of acute gastroenteritis of non-food origin.
The majority of these last ones were recorded in residences for elderly people (48 outbreaks), followed by residences for people with disabilities (4 outbreaks).
Increase in foodborne outbreaks
In parallel, foodborne outbreaks rose to 101, 2% more than the previous year, with an incidence of 1.40 outbreaks per 100,000 inhabitants.
The associated cases were 1,219, which represents a global reduction of 20%, and 49 admissions were recorded, 4% of the total. Although hospitalizations increased by 14%, no deaths were recorded, compared to two in the previous year.
67.35% of those affected, 821 people, were concentrated in 12 outbreaks with at least 20 positives each, all linked to food prepared or consumed in collective dining rooms, with a special weight from educational centers (five outbreaks).
Foodborne outbreaks in catering establishments were the most numerous, with 70 episodes (69.3% of the total). Next were outbreaks in homes or private spaces, with 14 (13.9%), and those recorded in school collectives, with six (5.9%).
The highest total number of cases occurred in schools, with 382 affected, 31.3% of the total. In contrast, the majority of hospitalizations were concentrated in catering establishments (25 admissions, 51%) and in private homes (21 admissions, 42.9%).
The BOA in food service establishments increased by 18.6% compared to 2024, although with a decrease of 24.5% in the number of associated cases. In private households, there was an increase in both reported outbreaks and hospitalizations (16.7% and 50%, respectively), accompanied by one third fewer cases.
A decrease in outbreaks was also recorded in senior centers and company cafeterias. The median number of cases per outbreak was 57 in educational centers (32 in 2024) and 3 in the outbreaks of food service establishments (also 3 in 2024) and in private homes (3.5 in 2024).
More than half of the BOA (55.4%) and almost a quarter of the cases (23.5%) were located in the municipality of Madrid, especially in the districts of Chamberí (8 outbreaks), Centro, and Salamanca (6 outbreaks each).
In 39 outbreaks (38.6%), the causal agent was confirmed. The most frequent pathogen was Salmonella (20 outbreaks), which accounted for the highest number of cases (123) and hospitalizations (45). Following were Campylobacter (5 BOA), S. aureus (4), and B. cereus and biogenic amines (3 BOA each).
In terms of sick individuals and hospitalizations, Salmonella was also the predominant agent, with 36.8% of cases and 93.8% of hospitalizations. The outbreaks caused by norovirus and biogenic amines stood out for the average number of affected: 32.5 and 12 cases per outbreak, respectively, compared to the outbreaks caused by Salmonella (4 cases on average), S. aureus (3.5), and Campylobacter (3).
Impact of influenza and other diseases
Additionally, another 220 outbreaks of various pathologies were reported, totaling 1,897 cases and 476 hospitalizations. Among them, influenza outbreaks stood out, with 79 episodes. As a result of these outbreaks, 1,033 cases and 362 hospitalizations were recorded in 2025, accounting for 35% of the total.
In year-on-year comparison, influenza outbreaks increased from 17 to 79, which means multiplying by 4.6; associated cases rose from 177 to 1,033, almost six times more; and hospitalizations increased from 60 to 362, also six times more, according to data consulted by Europa Press.
This group also recorded 21 deaths, located in 14 senior residences and in two residences for people with disabilities, which triples the seven deaths reported the previous year.
After the flu, scabies outbreaks took the next place in frequency, with 47 episodes that caused 425 cases and 65 admissions (78.3% of them), while pulmonary tuberculosis accounted for 35 outbreaks with 83 cases. In this last case, 65 hospitalizations and two deaths in private homes were recorded, in people with previous risk factors.
They were followed by hepatitis A outbreaks, with 30 episodes that caused 62 cases and 42 admissions (67.7% of those affected).
Outbreaks of chickenpox were also reported (6 outbreaks with 42 cases), of scarlet fever (3 outbreaks with 18 cases), of impetigo (3 outbreaks with 17 cases), of respiratory syncytial virus infection (2 outbreaks with 10 cases), of mpox (2 outbreaks with 6 cases) and one outbreak of legionellosis (2 cases) and of tularemia (2 cases). In addition, a death linked to an outbreak of legionellosis occurred in a nursing home.