ECDC calls for the monitoring of respiratory viruses throughout the year, after COVID-19 and some epidemics no longer adhere to the winter season.

European states should monitor influenza, COVID-19, and respiratory syncytial virus throughout the year, including in the summer months, to detect new variants, unexpected increases in infections, and pressure on hospitals more quickly. The European Centre for Disease Prevention and Control proposes a common system that brings together data on mild cases, hospitalizations, laboratory results, and the genetic characteristics of the viruses.

In short

ECDC recommends that surveillance of respiratory viruses continue throughout the year, as SARS-CoV-2 has not turned into a winter-exclusive virus, and outbreaks of influenza and respiratory syncytial virus can occur outside the usual season. Even during periods with few cases, states should maintain the capacity to identify, assess, and communicate unusual signals quickly.

The basic system would combine information received from family doctors, hospitals, laboratories, and teams that sequence the viruses. The data must show not only how many people become ill but also which categories are more exposed to severe forms, how many patients reach intensive care, and whether more transmissible or treatment-resistant variants appear.

ECDC considers that hospital surveillance is essential and cannot be replaced by other sources. States are encouraged to monitor hospitalized patients with severe respiratory infections, to record their progress, and to combine this information with testing for influenza, SARS-CoV-2, and respiratory syncytial virus.

Data from wastewater, mortality, hospital occupancy, drug sales, absenteeism, and voluntary reports from the population can complement the system. However, ECDC warns that these sources alone do not provide sufficient information about the age of patients, the severity of the disease, or the viral variant and must be interpreted alongside medical data.

The collected information must be used for concrete decisions, such as the timing of vaccination campaigns, recommendations regarding antivirals, preparation of beds and medical staff, or protective measures during periods of increased transmission. ECDC will publish additional modules in 2026 and 2027 regarding system dimensions, alert thresholds, electronic medical records, and possible surveillance through wastewater.

The European Centre for Disease Prevention and Control has published a new framework for the integrated monitoring of respiratory viruses in the European Union and the European Economic Area. The document mainly covers influenza, SARS-CoV-2, respiratory syncytial virus, known by the acronym RSV, and other viruses that cause acute respiratory infections.

Traditional systems often monitored each virus separately and focused mainly on the cold season. ECDC now recommends bringing together epidemiological and laboratory information to build a common picture of respiratory infections, from mild cases treated in primary care to hospitalizations, intensive care, and deaths.

The new framework aims to achieve three objectives. Authorities must monitor where, when, and in which groups respiratory diseases spread, track genetic and biological changes in the viruses, and assess the burden of disease, vaccine effectiveness, and the impact of public health interventions.

Family doctors and other primary care services can provide the first signals regarding the increase in virus circulation in the community. Some patients with symptoms of influenza or acute respiratory infection should be tested according to common protocols, so that authorities can estimate which viruses are causing illnesses and how quickly they spread.

ECDC places particular importance on monitoring severe cases in hospitals. Systems should include hospitalized patients with severe acute respiratory infections, record age, pre-existing conditions, admission to intensive care, discharge or death, and associate this information with test results.

Monitoring only positive tests from hospitals can produce an incomplete picture, as testing practices vary between hospitals, periods, and patient categories. ECDC prefers a system in which patients are included based on a standardized clinical definition of severe respiratory disease, and testing for multiple viruses is integrated into surveillance.

Laboratories must maintain the capacity to identify types and subtypes of influenza viruses and to sequence influenza, SARS-CoV-2, and RSV. These analyses can detect new genetic lines, changes that affect transmission or severity, and potential differences between circulating viruses and the composition of vaccines.

ECDC recommends using multiplex PCR tests, which can simultaneously detect multiple respiratory viruses. All positive samples for influenza from surveillance centers should be typed and subtyped, including to detect unusual influenza viruses from animals that may appear outside the season.

States that cannot perform certain complex analyses should send samples to European laboratories or reference centers of the World Health Organization. The exchange of samples and data allows for risk assessment at the European level even if a new variant initially appears in a small number of countries.

Surveillance must be maintained in the summer. ECDC shows that SARS-CoV-2 does not currently have an exclusively seasonal pattern, and outbreaks of influenza and RSV can occur outside the winter months. Influenza viruses detected in the summer can provide clues about the next season and how well vaccines match the strains that begin to circulate.

States with limited resources can reduce the intensity of some activities during quiet periods but must maintain a minimum level of monitoring and the capacity to rapidly expand testing. ECDC recommends that hospital surveillance be protected even during periods of limited budgets or staff, as it cannot be easily replaced by other systems.

Main data can be supplemented by monitoring mortality, outbreaks in nursing homes and other institutions, viruses in wastewater, and symptoms reported voluntarily through digital platforms. Information about hospital occupancy, vaccination coverage, vaccine effectiveness, drug sales, and absenteeism from schools or workplaces can provide additional signals.

Wastewater can show that a virus is circulating in the community before changes become visible in clinical data. However, this method cannot indicate alone the age of infected individuals, the severity of the disease, risk factors, or the exact variant and must be combined with patient testing and virus characterization.

ECDC includes among additional sources internet searches, posts about symptoms, purchases of medications for fever or cough, and increased absenteeism. These signals may indicate an intensification of transmission but can be influenced by public interest and media reports and do not confirm the existence of an outbreak on their own.

Data must be transformed into practical decisions. Authorities can use them to determine when to start vaccination campaigns, which groups receive priority, when doctors should be informed about the use of antivirals, and how hospitals are prepared for a wave of patients.

Hospital planning may include reserving beds, organizing respiratory wards, protecting staff, expanding testing, and preparing pediatric intensive care units. Recommendations to the public may include hand hygiene, avoiding crowds, wearing masks in certain situations, and additional measures for vulnerable groups.

ECDC sees electronic medical records and artificial intelligence as tools that can accelerate the collection and analysis of information. Automation could reduce dependence on manual reporting by doctors and could keep functional systems operational during periods when hospitals are under high demand.

The agency warns that electronic data varies between states, and the information collected for patient treatment is not always complete or comparable for surveillance. The use of artificial intelligence raises questions about data protection, governance, and the validity of methods.

The framework published in July 2026 is the first module of a system that will be

gradually completed. ECDC intends to publish modules throughout the year regarding the number and frequency of samples that need to be analyzed and the thresholds used to identify outbreaks, and for 2027, it is preparing guidelines regarding surveillance based on electronic medical records.

The document allows each state to adapt the system to the structure of medical services, resources, and local risks, but requires the use of definitions and methods close enough for the data to be comparable at the European level. ECDC publishes weekly the information transmitted by states in the European synthesis on respiratory viruses.

https://2eu.brussels/ro/news/ecdc-cere-monitorizarea-virusurilor-respiratorii-tot-anul-dupa-ce-covid-19-si-unele-epidemii-nu-mai-respecta-sezonul-de-iarna