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This Guidelines summary covers key information on the 2021–2022 national flu programme, including:

  • recommendations for the use of the vaccines
  • eligibility
  • other groups
  • dosage and schedule
  • administration
  • vaccines for the national immunisation programme
  • contraindications
  • adverse reactions.

The following recommendations are not included in this summary:

  • flu vaccination in people who have:
    • immunosupression and/or HIV infection
    • severe asthma or active wheezing
    • egg allergy
  • use with antiviral agents against flu
  • exposure of healthcare professional to live attenuated flu vaccine viruses
  • inadvertent administration of LAIV.

The summary includes information from Influenza: the green book, Chapter 19The national influenza immunisation programme 2021 to 2022, and All influenza vaccines available in the UK for the 2021 to 2022 season.

See the full guidelines for a complete list of recommendations.


This summary has been abridged for print. View the full summary at guidelines.co.uk/454313.article

Recommendations for the use of the vaccines

The objectives of the flu immunisation programme are to protect those who are most at risk of serious illness or death should they develop flu and to reduce transmission of the infection, thereby contributing to the protection of vulnerable patients who may have a suboptimal response to their own immunisations.

As a result of non-pharmaceutical interventions in place for COVID-19, flu activity levels were extremely low globally in 2020–2021. As a result, a lower level of population immunity against flu is expected in 2021–2022. In the situation where social mixing and social contact return towards pre-pandemic norms, it is expected that winter 2021–2022 will be the first winter in the UK when seasonal flu virus (and other respiratory viruses) will co-circulate alongside COVID-19.

Seasonal flu and COVID-19 viruses have the potential to add substantially to the winter pressures usually faced by the NHS, particularly if infection waves from both viruses coincide. The timing and magnitude of potential flu and COVID-19 infection waves for winter 2021–2022 are currently unknown, but mathematical modelling indicates the 2021–2022 flu season in the UK could be up to 50% larger than typically seen. 

Flu vaccination is therefore an important priority this coming autumn to reduce morbidity and mortality associated with flu, and to reduce hospitalisations during a time when the NHS and social care may also be managing winter outbreaks of COVID-19.


  • Those eligible for NHS flu vaccination in 2021–2022 are:
    • all children aged 2–15 (but not 16 years or older) on 31 August 2021
    • those aged 6 months to under 50 years in clinical risk groups
    • pregnant women
    • those aged 50 years and over
    • those in long-stay residential care homes
    • carers
    • close contacts of immunocompromised individuals
    • frontline health and social care staff employed by:
      • a registered residential care or nursing home
      • registered domiciliary care provider
      • a voluntary managed hospice provider
      • direct payment (personal budgets) and/or personal health budgets, such as personal assistants
  • All frontline health and social care workers are expected to have flu vaccination to protect those they care for
  • The flu chapter in the Green Book gives detailed descriptions of the groups outlined above and guidance for healthcare workers on administering the flu vaccine.

Table 1: Clinical risk groups who should receive flu immunisation

Clinical risk categoryExamples (this list is not exhaustive and decisions should be based on clinical judgement)

Chronic respiratory disease

Asthma 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

Congenital heart disease, hypertension with cardiac complications, chronic heart failure, individuals requiring regular medication and/or follow-up for ischaemic heart disease

Chronic kidney disease

Chronic kidney disease at stage 3, 4, or 5, chronic kidney failure, nephrotic syndrome, kidney transplantation

Chronic liver disease

Cirrhosis, biliary atresia, and chronic hepatitis

Chronic neurological disease (included in the DES directions for Wales)

Stroke, transient ischaemic attack. Conditions in which respiratory function may be compromised due to neurological disease (e.g. polio syndrome sufferers.) Clinicians should offer immunisation, based on individual assessment, to clinically vulnerable individuals including those with cerebral palsy, learning disabilities, multiple sclerosis and related, or similar conditions; or hereditary and degenerative disease of the nervous system or muscles; or severe neurological disability


Type 1 diabetes, type 2 diabetes requiring insulin or oral hypoglycaemic drugs, diet controlled diabetes

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, bone marrow transplant, HIV infection at all stages, multiple myeloma or genetic disorders affecting the immune system (e.g. IRAK-4, NEMO, complement disorder)


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


It is difficult to define at what level of immunosuppression a patient could be considered to be at a greater risk of the serious consequences of flu and should be offered flu vaccination. This decision is best made on an individual basis and left to the patient’s clinician


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

Asplenia or dysfunction of the spleen

This also includes conditions such as homozygous sickle cell disease 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 body mass index ≥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

Other 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

  • Starting from September 2013, an extension of the programme to all children aged 2 to less than 17 years old is being phased in from the youngest age groups. See the respective annual flu letters for England and the devolved administrations for the cohorts of children that are eligible for flu vaccination for the coming/current season
  • A single dose of live attenuated influenza vaccine (LAIV) should be offered per season, unless contraindicated, irrespective of whether flu vaccine has been received previously.

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.

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. 
  • Children aged 2 to less than 9 years old who have not received flu vaccine previously should be offered a second dose of the vaccine at least 4 weeks later.

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 cohortVaccine available: children in clinical risk groups[A]Vaccine available: children not in clinical risk groups[B]

6 months to less than 2 years old

Offer suitable quadrivalent inactivated flu vaccine

Not applicable

Children aged 2 years to less than 18 years old[B]

Offer LAIV (Fluenz® Tetra) (unless medically contraindicated)[C]

Offer LAIV (Fluenz® Tetra)

[A] Children in clinical risk groups aged six month to less than nine years 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
  • Whilst 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 test eligible girls for pregnancy or to advise avoidance of pregnancy in those who have been recently vaccinated.

Frontline health and social care workers

  • All frontline health and social care workers should receive a vaccination this season. This should be provided by their employer, in order to meet their responsibility to protect their staff and patients and ensure the overall safe running of services
  • Employers should commission a service that makes access easy to the vaccine for all frontline staff, encourage staff to get vaccinated, and monitor the delivery of their programmes.

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 0.25ml or 0.5ml dose. The JCVI has advised where these alternative doses are indicated in the SPCs, the 0.5ml 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.

For information on administration, and all influenza vaccines marketed in the UK for the 2020/21 season, see the full summary at guidelines.co.uk/454313.article

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.
  • Flu viruses change continuously and the World Health Organization monitors the epidemiology of flu viruses throughout the world making recommendations about the strains to be included in vaccines, with recommendations now confirmed for 2021–2022
  • Providers should ensure that they have ordered adequate supplies of the recommended vaccines for their different patient groups, as set out in two letters from NHS England and NHS Improvement on 03 February and on 01 April 2021
  • In summary the recommended vaccines are:
    • for those aged 65 years and over—the adjuvanted quadrivalent influenza vaccine (aQIV), with the cell-based quadrivalent influenza vaccine (QIVc) or the recombinant quadrivalent influenza vaccine (QIVr) offered if aQIV is unavailable
    • for under-65s (including those at risk, pregnant women, and 50–64-year-old cohort) offer QIVc or QIVr, as an alternative if these are not available, the egg-grown quadrivalent influenza vaccine (QIVe) should be considered for use
  • Public Health England procures vaccines for the children’s programme and these can be ordered through Immform. The LAIV should be offered to eligible children aged 2 years and over, unless contraindicated. QIVc, which is now licensed for all children aged 2 years and above, will be available to order for children in at-risk groups who are contraindicated to receive LAIV, and as an alternative offer for children aged 2 and over whose parents object to LAIV on the ground of its porcine gelatine content. Children in clinical risk groups aged 6 months to less than 2 years should be offered QIVe.

Table 3: All influenza vaccines marketed in the UK for the 2021–2022 season

SupplierProduct detailsVaccine typeAge indicationsOvalbumin contentContact details

AstraZeneca UK Ltd


Quadrivalent LAIV (live attenuated influenza vaccine) supplied as nasal spray suspension

From 24 months to less than 18 years of age

<0.024 mcg per 0.2 ml dose)

0845 139 0000


Quadrivalent influenza vaccine

QIVe (standard egg-grown quadrivalent influenza vaccine), split virion, inactivated

From 6 months

≤0.05 mcg per 0.5 ml dose

0113 238 7552

Sanofi Pasteur Vaccines

Quadrivalent influenza vaccine

QIVe (standard egg-grown quadrivalent influenza vaccine), split virion, inactivated

From 6 months

≤0.05 mcg per 0.5 ml dose

0800 854 430

Viatris (formerly Mylan)

Quadrivalent Influvac® sub‑unit Tetra

QIVe (standard egg‑grown quadrivalent influenza vaccine), surface antigen, inactivated

From 6 months

≤0.1 mcg per 0.5 ml dose

0800 358 7468

Seqirus UK Ltd


QIVc (cell-grown quadrivalent influenza vaccine), surface antigen, inactivated

From 2 years


08457 451 500

Sanofi Pasteur Vaccines


QIVr (quadrivalent influenza vaccine (recombinant, prepared in cell culture))

From 18 years


0800 854 430

Seqirus UK Ltd

Fluad Tetra▼

aQIV (egg-grown quadrivalent influenza vaccine), surface antigen, inactivated, adjuvanted with MF59C.1

From 65 years

≤1 mcg per 0.5 ml dose



  • The SPCs for individual products should always be referred to when deciding which vaccine to give. There are very few individuals who cannot receive any flu vaccine. When there is doubt, appropriate advice should be sought promptly from the screening and immunisation team in the NHS England area team, a consultant in communicable disease control or a consultant paediatrician, so that the period the individual is left unvaccinated is minimised
  • None of the flu vaccines should be given to those who have had:
    • a confirmed anaphylactic reaction to a previous dose of the vaccine, or
    • a confirmed anaphylactic reaction to any component of the vaccine (other than ovalbumin—see the precautions section in chapter 19 of the Green Book)
  • LAIV should not be given to children or adolescents who are clinically severely immunocompromised due to conditions or immunosuppressive therapy such as: 
    • acute and chronic leukaemias
    • lymphoma
    • HIV infection not on highly active antiretroviral therapy
    • cellular immune deficiencies
    • high dose corticosteroids
  • It is not contraindicated for use in children or adolescents with stable HIV infection receiving antiretroviral therapy; or who are receiving topical corticosteroids, inhaled corticosteroids or low-dose systemic corticosteroids, or those receiving corticosteroids as replacement therapy, for example, for adrenal insufficiency
  • It is contraindicated in children and adolescents receiving salicylate therapy (other than for topical treatment of localised conditions) because of the association of Reye’s syndrome with salicylates and wild-type influenza infection as described in the SPC for Fluenz® Tetra.


  • Minor illnesses without fever or systemic upset are not valid reasons to postpone immunisation. If an individual is acutely unwell, immunisation may be postponed until they have fully recovered. 

Adverse reactions

  • Pain, swelling, or redness at the injection site; low-grade fever; malaise; shivering; fatigue; headache; myalgia; and arthralgia are among the commonly reported symptoms after IM or intradermal vaccination
  • A small painless nodule (induration) may also form at the injection site. These symptoms usually disappear within 1–2 days without treatment. Nasal congestion/rhinorrhoea, reduced appetite, weakness, and headache are common adverse reactions following administration of LAIV
  • Immediate reactions such as urticaria, angioedema, bronchospasm, and anaphylaxis can occur.


Full guidelines:

Public Health England. Influenza: the Green Book, chapter 19. October 2020.


Public Health England. Influenza vaccine: ovalbumin content. June 2021.


Department of Health and Social Care, Public Health England, NHS England. The national flu immunisation programme 2021 to 2022. July 2021.


Contains public sector information licensed under the Open Government Licence v3.0.

Published date: March 2013.

Last updated: July 2021.