Risk groups for severe influenza
The influenza risk groups include people who are more likely than others to develop severe disease, resulting in hospitalisation or death, if they should be infected. The most recent published ECDC review indicated strong evidence for immunising two large risk groups:
- Older adults
- All persons (over six months of age) with chronic medical conditions
There is no sharp cut-off age for older adults, however many countries use the age of 65 years as a threshold, while other countries use younger ages.
The list of chronic medical conditions in patients often recommended for vaccination in EU/EEA Member States include diseases affecting the following:
- respiratory system e.g. asthma
- cardiovascular system e.g. coronary artery disease
- endocrine system e.g. diabetes
- hepatic system e.g. liver cirrhosis
- renal system e.g. chronic renal failure
- neurological/neuromuscular conditions e.g. parkinsonism
In addition to the above:
- any condition compromising respiratory functions e.g. morbid obesity (BMI > 40), physical handicap in children and adults
- immunosuppression due to disease or treatment including due to haematological conditions and HIV infection.
The WHO Strategic Advisory Group of Experts on Immunization (SAGE) recommends that pregnant women be prioritised for immunisation above all groups. It also advises that the following groups be immunised:
- young children
- women up to 2 weeks postpartum
- individuals younger than 19 years of age on long-term aspirin or salicylate-containing medications
- older people
- individuals over six months of age with chronic conditions
- healthcare workers with patient contact
This guidance is described in a 2012 position paper and background paper on influenza vaccination, updating its 2005 guidance.
Public health guidance: Seasonal influenza vaccination of children and pregnant women
The aim of this guidance document is to provide EU/EEA Member States and EU bodies with relevant information to make an informed decision on routine vaccination of healthy children and pregnant women with seasonal influenza vaccine. The options presented in this document are based on a systematic review of the literature and the opinions of a group of independent experts.
Expert opinion on priority risk groups for influenza vaccination
This paper identifies and describes population groups at increased risk for severe outcomes of influenza (“risk groups”) and advocates vaccination for two major groups, namely a) persons in the older age group, usually 65 years and older; and b) persons with chronic medical conditions.
Determinants of Fatal Outcome in Patients Admitted to Intensive Care Units With Influenza, European Union 2009–2017
Morbidity, severity, and mortality associated with annual influenza epidemics are of public health concern. We analyzed surveillance data on hospitalized laboratory-confirmed influenza cases admitted to intensive care units to identify common determinants for fatal outcome and inform and target public health prevention strategies, including risk communication.
Read more on external websites
WHO Strategic Advisory Group of Experts on immunization