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Summary for primary care

Summary of Flu Immunisation Guidance for England 2023–2024

Latest Guidance Updates

08 June 2023: eligible cohorts updated in the national flu immunisation programme 2023–2024 letter, and new information on chronic respiratory disease and chronic heart disease added to the clinical risk groups table. New information added to the table on vaccination for children under 18 years old.


This Guidelines summary covers key information on the 2023–2024 national flu programme, including:

  • eligibility
  • other risk groups
  • dosage and schedule
  • administration
  • vaccines for the national immunisation programme
  • contraindications
  • adverse reactions.
The summary includes information from Influenza: the Green Book, chapter 19The national influenza immunisation programme 2023 to 2024, and All influenza vaccines available in the UK for the 2023 to 2024 season.

See the full guidelines for a complete list of recommendations, including recommendations on use with antivirals, agents against flu, exposure of healthcare professionals to live attenuated flu vaccine (LAIV) viruses, inadvertent administration of LAIV, and flu vaccination in people who have immunosuppression and/or HIV infection, severe asthma or active wheezing, or egg allergy.

Reflecting on your Learnings

Reflection is important for continuous learning and development, and a critical part of the revalidation process for UK healthcare professionals. Click here to access the Guidelines Reflection Record.


  • The below groups will be eligible for a flu vaccine from 1 September 2023:
    • those aged 65 years and over
    • those aged 6 months to under 65 years in clinical risk groups (as defined by the Green Book, chapter 19)
    • pregnant women
    • all children aged 2 or 3 years on 31 August 2023
    • primary school aged children (from reception to year 6)
    • those in long-stay residential care homes
    • carers in receipt of carer's allowance, or those who are the main carer of an elderly or disabled person
    • close contacts of immunocompromised individuals
    • front-line workers in a social care setting without an employer-led occupational health scheme, including those working for a registered residential care or nursing home, registered domiciliary care providers, voluntary managed hospice providers, and those that are employed by those who receive direct payments (personal budgets) or personal health budgets, such as personal assistants
  • All front-line healthcare workers, including both clinical and nonclinical staff who have contact with patients, should be offered a flu vaccine as part of the organisations' policy for the prevention of the transmission of flu to help protect both staff and those that they care for.

Table 1: Clinical Risk Groups That Should Receive Flu Immunisation

Clinical Risk CategoryExamples (This List is Not Exhaustive and Decisions Should be Based on Clinical Judgement)
Chronic respiratory diseaseAsthma that requires continuous or repeated use of inhaled or systemic steroids or with previous exacerbations requiring hospital admission

Chronic obstructive pulmonary disease including chronic bronchitis and emphysema; bronchiectasis, cystic fibrosis, interstitial lung fibrosis, pneumoconiosis, and bronchopulmonary dysplasia

Children who have previously been admitted to hospital for lower respiratory tract disease

See the precautions section in chapter 19 of the Green book

Chronic heart disease and vascular diseaseCongenital heart disease, hypertension with cardiac complications, chronic heart failure, individuals requiring regular medication and/or follow-up for ischaemic heart disease. This includes individuals with atrial fibrillation, peripheral vascular disease or a history of venous thromboembolism.
Chronic kidney diseaseChronic kidney disease at stage 3, 4, or 5, chronic kidney failure, nephrotic syndrome, kidney transplantation
Chronic liver diseaseCirrhosis, biliary atresia, and chronic hepatitis
Chronic neurological disease (included in the DES directions for Wales)Stroke, TIA. Conditions in which respiratory function may be compromised due to neurological or neuromuscular disease (e.g. polio syndrome sufferers.) Clinicians should offer immunisation, based on individual assessment, to clinically vulnerable individuals including those with cerebral palsy, PMLD, Down's syndrome, multiple sclerosis, dementia, Parkinson's disease, motor neurone disease and related or similar conditions; or hereditary and degenerative disease of the nervous system or muscles; or severe neurological disability
Diabetes and adrenal insufficiencyType 1 diabetes, type 2 diabetes requiring insulin or oral hypoglycaemic drugs, diet controlled diabetes. Addison's disease, secondary or tertiary adrenal insufficiency requiring steroid replacement
Immunosuppression (see contraindications and precautions section in chapter 19 of the Green book)Immunosuppression due to disease or treatment, including patients undergoing chemotherapy leading to immunosuppression, patients undergoing radical radiotherapy, solid organ transplant recipients, bone marrow or stem cell transplant recipients, people living with HIV (at all stages), multiple myeloma or genetic disorders affecting the immune system (for example IRAK-4, NEMO, complement disorder, SCID). Individuals who are receiving immunosuppressive or immunomodulating biological therapy including, but not limited to, anti-TNF-alemtuzumab,ofatumumab, rituximab, patients receiving protein kinase inhibitors or  PARP inhibitors, and individuals treated with steroid sparing agents such as cyclophosphamide and mycophenolate mofetil

Individuals treated with or likely to be treated with systemic steroids for more than a month at a dose equivalent to prednisolone at 20 mg or more per day (any age), or for children under 20 kg, a dose of 1 mg or more per kg per day

Anyone with a history of haematological malignancy, including leukaemia, lymphoma, and myeloma and those with systemic lupus erythematosus and rheumatoid arthritis, and psoriasis who may require long term immunosuppressive treatments

Some immunocompromised patients may have a suboptimal immunological response to the vaccine

Asplenia or dysfunction of the spleenThis also includes conditions such as homozygous sickle cell disease, hereditary spherocytosis, thalassemia major, and coeliac syndrome that may lead to splenic dysfunction
Pregnant women

Pregnant women at any stage of pregnancy (first, second, or third trimesters)

See the precautions section in chapter 19 of the Green Book

Morbid obesity 

(class III obesity)[A]

Adults with a BMI ≥40 kg/m2
[A] Many of this patient group will already be eligible due to complications of obesity that place them in another risk category

BMI=body mass index; IRAK-4=interleukin-1 receptor-associated kinase 4; NEMO=nuclear factor-kappa B essential modulator; PMLD=profound and multiple learning disabilities;SCID=severe combined immunodeficiency; TIA=transient ischaemic attack

Other Risk Groups

  • The list in Table 1 is not exhaustive, and the medical practitioner should apply clinical judgement to take into account the risk of flu exacerbating any underlying disease that a patient may have, as well as the risk of serious illness from flu itself. Flu vaccine should be offered in such cases even if the individual is not in the clinical risk groups specified in Table 1
  • Vaccination should also be offered to household contacts of immunocompromised individuals, that is, individuals who expect to share living accommodation on most days over the winter and therefore for whom continuing close contact is unavoidable. This may include carers.


  • The Joint Committee on Vaccination and Immunisation (JCVI) has advised the use of different dosage schedules of flu vaccine for children depending on their age, the clinical indications, the type of vaccine offered, and whether they have received flu vaccine previously. This advice differs from some of the summaries of product characteristics (SPCs).

Children Aged 2 to Less Than 17 Years Old NOT in Clinical Risk Groups

  • LAIV should be offered per season, unless contraindicated, irrespective of whether flu vaccine has been received previously.

Children Aged 6 Months to Less Than 18 Years of Age who are Household Contacts of Immunocompromised Individuals

  • Children who are household contacts of immunocompromised individuals should be vaccinated in accordance with the advice on children in clinical risk groups. Inactivated vaccine may need to be given instead of LAIV.

Children Aged 6 Months to Less Than 2 Years of Age IN Clinical Risk Groups

  • These children should be offered the recommended inactivated quadrivalent flu vaccine. Those who have not received flu vaccine previously should be offered a second dose of vaccine, at least 4 weeks later
  • The flu vaccines are interchangeable; the second dose, if required, should be given at least 4 weeks after the first dose in accordance with the manufacturer's SPC for that vaccine
  • LAIV is not licensed or recommended for children under 2 years of age. QIVc is not licensed for use under 2 years of age. For egg-allergic children under 2 years, it is advised that QIVc is offered off-label. 

Children Aged 2 to Less Than 18 Years of Age IN Clinical Risk Groups

  • Children aged 2 years to less than 18 years in clinical risk groups should be offered LAIV unless it is medically contraindicated or otherwise unsuitable
  • Those children who have never received flu vaccine before and are aged between 2 and less than 9 years should be offered a second dose of LAIV at least 4 weeks later. If LAIV is unavailable for this second dose (due to batch expiry) an inactivated flu vaccine can be given
  • For those children in clinical risk groups for whom LAIV is medically contraindicated, a suitable quadrivalent inactivated flu vaccine should be offered. 

Preterm Infants

  • It is important that preterm infants who have risk factors have their immunisations at the appropriate chronological age. Flu immunisation should be considered after the child has reached 6 months of age.

Table 2: Flu Vaccination for Children Under 18 Years Old

Eligible CohortChildren in Clinical Risk Groups and Children who are Household Contacts of Immunocompromised Individuals[A]Children Not in Clinical Risk Groups[B]
6 months to less than 2 years oldOffer suitable quadrivalent inactivated flu vaccineNot applicable
2 years to less than 18 years old[B]Offer LAIV (unless medically contraindicated[C])Offer LAIV[B]
9 years to less than 18 years oldOffer LAIV (unless medically contraindicated[C])Offer LAIV[B]
[A] Children in clinical risk groups who have not received flu vaccine before should be offered two doses of the appropriate flu vaccine (given at least 4 weeks apart) 

[B] Please see the respective annual flu letters for England and the Devolved Administrations for the cohorts of children not in clinical risk groups that are eligible for flu vaccination for the coming/current season 

[C] If LAIV is medically contraindicated or otherwise unsuitable, then offer quadrivalent inactivated flu vaccine
LAIV=live attenuated influenza vaccine


  • Pregnant women should be offered inactivated flu vaccine as the risk of serious illness from flu is higher in pregnant women
  • Inactivated flu vaccine can be safely and effectively administered during any trimester of pregnancy
  • Although there is no evidence of risk with LAIV, inactivated flu vaccines are preferred for those who are pregnant. There is no need, however, to specifically ask about or test for pregnancy when offering LAIV to eligible girls, or to advise avoidance of pregnancy in those who have been recently vaccinated.

Dosage and Schedule

  • The dosages and schedules for the flu vaccines should be given according to the recommendations for the use of the vaccine
  • Some of the SPCs for intramuscular (IM) inactivated flu vaccines indicate that young children can be given a 0.25 ml or 0.5 ml dose. The JCVI has advised where these alternative doses are indicated in the SPCs, the 0.5 ml dose of IM inactivated flu vaccines should be given to infants aged 6 months or older and young children because there is evidence that this dose is effective in young children
  • Children aged 6 months to under 9 years who are in clinical risk groups and have not received flu vaccine previously should be offered a second dose of vaccine
  • The JCVI has advised that children aged 2 years to under 9 years of age who are not in a clinical risk group, only require a single dose of LAIV irrespective of whether they have received flu vaccine previously. This advice differs from that in the SPC for Fluenz® Tetra
  • Children who have received one or more doses of any flu vaccine before (including pandemic monovalent influenza A[H1N1]v vaccine) should be considered as previously vaccinated.


  • The inactivated influenza vaccines should normally be given into the upper arm (or anterolateral thigh in infants) preferably by IM injection. Influenza vaccines licensed for IM or subcutaneous (SC) administration may alternatively be administered by the SC route
  • There is a lack of evidence that the SC route of vaccination is any safer than the IM route in people taking anticoagulants. The SC route can itself be associated with an increase in localised reactions
  • Individuals on stable anticoagulation therapy, including individuals on warfarin who are up to date with their scheduled International Normalised Ratio (INR) testing and whose latest INR was below the upper threshold of their therapeutic range, can receive IM vaccination
    • a fine needle (23 or 25 gauge) should be used for the vaccination, followed by firm pressure applied to the site (without rubbing) for at least 2 minutes
    • if in any doubt, consult with the clinician responsible for prescribing or monitoring the individual's anticoagulant therapy
  • Individuals with bleeding disorders may be vaccinated intramuscularly if, in the opinion of a doctor familiar with the individual's bleeding risk, vaccines or similar small-volume IM injections can be administered with reasonable safety by this route
    • a fine needle (23 or 25 gauge) should be used for the vaccination, followed by firm pressure applied to the site (without rubbing) for at least 2 minutes
    • the individual/parent/carer should be informed about the risk of haematoma from the injection
  • The LAIV is administered by the intranasal route (Fluenz® Tetra) and is supplied in an applicator that allows a divided dose to be administered in each nostril (total dose of 0.2 ml, 0.1 ml in each nostril):
    • administration of either dose does not need to be repeated if the patient sneezes or blows their nose following administration
    • as heavy nasal congestion might impede delivery of the vaccine to the nasopharyngeal mucosa, deferral of administration until resolution of the nasal congestion should be considered, or if appropriate, an alternative intramuscularly administered influenza vaccine
  • Inactivated influenza vaccines can be given at the same time as other vaccines. LAIV can also be given at the same time as other live or inactivated vaccines
  • Although it was previously recommended that, where vaccines cannot be administered simultaneously, a 4-week interval should be observed between live viral vaccines. The JCVI has advised that no specific intervals need to be observed between LAIV and other live vaccines
  • IM vaccines should be given at separate sites, preferably in a different limb. If given in the same limb, they should be given at least 2.5 cm apart
  • As a wide variety of flu vaccines are on the UK market each year, it is especially important that the exact brand of vaccine, batch number, and site at which each vaccine is given is accurately recorded in the patient records. Where the vaccine is given for occupational reasons, it is recommended that the employer keep a vaccination record
  • It is important that vaccinations given either at a general practice or elsewhere (for example, at community pharmacies or antenatal clinics) are recorded on appropriate health records for the individual (using the appropriate clinical code) in a timely manner. If given outside of general practice, a record of vaccination should be returned to the patient's general practice to allow clinical follow up and to avoid duplicate vaccination.

Flu and COVID-19 Vaccination

  • Booster vaccines for COVID-19 are currently under consideration, with trials underway to ascertain whether co-administration of COVID-19 and flu vaccines will be permissible, subject to the advice of JCVI
  • Early evidence on the concomitant administration of COVID-19 and flu vaccines used in the UK, supports the delivery of both vaccines at the same time where appropriate
  • Planning for flu vaccination should continue as usual for this autumn, with further advice issued should co-administration with COVID-19 vaccination be recommended so that where appropriate both vaccines could be given at the same time.


  • Vaccination should be given in sufficient time to ensure patients are protected before flu starts circulating. If an eligible patient presents late for vaccination it is generally appropriate to still offer it. This is particularly important if it is a late flu season or when newly at-risk patients present, such as pregnant women who may not have been pregnant at the beginning of the vaccination period
  • The decision to vaccinate should take into account the fact that the immune response to vaccination takes about 2 weeks to fully develop
  • Parents of any child at risk from flu because of an underlying medical condition can choose to receive flu vaccination in general practice, especially if the parent does not want their child to have to wait for the school vaccination session (which may be one of the later sessions of the season). General practices should invite these children for vaccination, making it clear that parents have the option to have their child vaccinated in general practice.

Adult Vaccines Eligible for Reimbursement

  • Those aged 65 years and over
    • Adjuvanted quadrivalent influenza vaccine (aQIV)/recombinant quadrivalent influenza vaccine (QIVr)
    • Cell-based quadrivalent influenza vaccine (QIVc)—only when every attempt to use aQIV or QIVr has been exhausted
  • Those aged 18–64 years in eligible groups
    • QIVc/QIVr
    • Egg-grown quadrivalent influenza vaccine (QIVe)—only when every attempt to use QIVc or QIVr has been exhausted
    • As in previous years, aQIV may be offered 'off-label' to those who become 65 years of age before 31 March 2024.