Which Flu Vaccine Will You Get? Nasal Spray, Adjuvanted, Cell-Based and High-Dose Explained

Ask ten people what flu vaccine they had last winter and most will say “the flu jab”. In fact there are now six distinct types of flu vaccine in use in the UK, made in different ways and recommended for different ages. Knowing which one you are being offered, and why, makes it easier to judge the advice you are given and to ask the right questions.

This page explains each type of flu vaccine used in the UK in 2026/27, who it is designed for, and how the choice is made for adults, children and people in special situations. It is part of our complete guide to flu vaccines for 2026/27, which also covers effectiveness, pregnancy and side effects.

Why there is more than one flu vaccine

For decades almost every flu vaccine was made the same way: virus grown in fertilised hens’ eggs, then inactivated and purified. That method still works, but it has two weaknesses. First, as the virus adapts to grow in eggs it can pick up small changes, particularly in the H3N2 strain, so the vaccine matches circulating viruses less closely. Second, older immune systems respond less strongly to a standard dose, so standard vaccines protect older people less well.

Newer vaccines tackle one or both problems. Cell-based and recombinant vaccines avoid eggs altogether. Adjuvanted and high-dose vaccines give an ageing immune system a stronger signal. The Joint Committee on Vaccination and Immunisation (JCVI) weighs the evidence each year and lists the preferred vaccines for each age group, and the NHS buys accordingly.

Cell-based flu vaccine

The cell-based vaccine is grown in mammalian cells in a controlled culture rather than in eggs. It is an inactivated, surface antigen vaccine, given as an injection into the upper arm muscle, and it is licensed from 6 months of age. Because no eggs are involved at any stage it is egg-free, and the vaccine strains are not subject to egg adaptation.

JCVI lists the cell-based vaccine among the preferred vaccines for every age group from 6 months, including people aged 65 and over. For 2026/27 the NHS in Scotland has bought the cell-based vaccine for adults aged 18 to 64 and for children who cannot have the nasal spray.

Recombinant flu vaccine

The recombinant vaccine takes a different route. Instead of growing flu virus, it uses the genetic sequence of the haemagglutinin protein to produce that protein in insect cells. The result is a vaccine containing only the target protein, with no egg and no flu virus involved in manufacture. It is licensed from 18 years of age.

JCVI prefers it for adults of all ages alongside the cell-based vaccine. UK data cited in the national guidance found it at least as effective as the other enhanced vaccines in older adults in recent seasons.

Adjuvanted flu vaccine

An adjuvant is an ingredient that strengthens the immune response to a vaccine. The adjuvanted flu vaccine used in the UK contains an oil-in-water adjuvant called MF59 and is licensed from 50 years of age. It was developed for older people, whose immune responses to vaccines decline with age, and evidence shows it gives higher antibody responses and better protection in that group than standard vaccines, including against hospital admission.

For 2026/27 the NHS in Scotland is offering the adjuvanted vaccine to people aged 65 and over, because of its stronger effect in that age group.

High-dose flu vaccine

The high-dose vaccine contains four times the standard amount of antigen for each strain. It is egg-grown and licensed from 60 years of age, and JCVI has advised it can be used off-label from age 50 in people in clinical risk groups. In trials in adults aged 65 and over it produced a stronger immune response and better protection than a standard-dose vaccine.

In the UK it is one of the preferred options for people aged 65 and over, alongside the adjuvanted, cell-based and recombinant vaccines. Which of these is used locally depends on what each NHS board has procured.

Standard egg-grown vaccine, and why it is now second line

The traditional egg-grown inactivated vaccine is still licensed from 6 months, and it remains effective in younger adults in many seasons. But because of lower effectiveness in older people, and the issue of egg adaptation, JCVI now recommends it for adults under 65 only when the preferred vaccines are not available, and advises against it altogether for anyone aged 65 or over.

The nasal spray vaccine for children

The children’s flu vaccine is a live attenuated vaccine, given as a quick spray into each nostril. Its viruses have been weakened and adapted to the cooler temperature inside the nose, so they cannot grow anywhere warmer, and the immunity they trigger sits right where flu first gets in. It is licensed for children and young people from 2 to under 18 years, and it is the first choice for that age group because it protects children well, is easy to give, and may protect better against drifted strains.

A runny or blocked nose for a few days is common afterwards. If a child sneezes or blows their nose straight after the spray, it does not need to be repeated.

Scottish children receive their flu vaccine through the NHS programme, mostly at school. The alternative injection is the cell-based vaccine.

Which type will you be offered?

If you are vaccinated privately, the same age-based principles apply, and the pharmacist names the product and the reason for it before vaccinating you. Whether you qualify for a free NHS vaccine at all is a separate question: Bruntsfield Pharmacy has set out who is eligible for a free flu jab in Scotland this winter.

Pregnancy, egg allergy and weakened immunity

Pregnancy. Pregnant women should be offered an injected (inactivated) vaccine, which can be given safely at any stage. The cell-based vaccine’s product information confirms it can be given in any trimester and during breastfeeding.

Egg allergy. Egg allergy is no longer a contraindication to any UK flu vaccine, whether egg-grown or not, and there is no need to seek out an egg-free vaccine for this reason alone. People who have had a severe reaction to a flu vaccine itself should be referred for specialist allergy assessment, as an alternative product without the responsible ingredient may be possible.

Weakened immunity. Reduced immunity is not a reason to avoid an inactivated vaccine, though the body may make a smaller response to it. Household contacts of people who are very severely immunocompromised, such as those isolating after a bone marrow transplant, may be advised to have an injected vaccine rather than the nasal spray.

How to get started

1. Book online. Pick a slot in the booking calendar on this page, or phone the clinic on 0131 563 6824.
2. Complete a short health check. We cover allergies, past vaccine reactions, pregnancy, anticoagulants and anything affecting your immunity, and check you are well today.
3. Attend your appointment. You are told which type of flu vaccine you are getting before it is injected into your upper arm muscle.
4. Leave knowing what to expect. We explain which side effects are normal over the next day or two and when to get advice.

Types of flu vaccine: your questions answered

Is one type of flu vaccine better than the others?

Not across the board. The best vaccine depends on your age. For people aged 65 and over, adjuvanted, high-dose, cell-based and recombinant vaccines are all preferred over standard egg-grown vaccine. For younger adults, cell-based and recombinant vaccines are preferred.

Can I choose which flu vaccine I have?

You can ask, but the choice is guided by your age, your health and which preferred vaccines are available. The NHS in Scotland offers one main product per age group. Privately, the same age guidance applies, and the product is named before you are vaccinated.

Is the cell-based flu vaccine egg-free?

Yes. It is grown in mammalian cells, so no eggs are used at any stage. The recombinant vaccine is also egg-free.

What does adjuvanted mean?

An adjuvant is an added ingredient that strengthens the immune response. The adjuvanted flu vaccine is designed for older adults, whose immune response to standard vaccines is weaker.

Why do children get a nasal spray instead of an injection?

The nasal spray protects children well, may cover drifted strains better and is easy to give. It is the first choice for children aged 2 to 17 unless there is a reason it is unsuitable.

Why is the vaccine called trivalent?

Because it covers three flu strains: two influenza A strains (H1N1 and H3N2) and one influenza B strain. Four-strain vaccines are no longer used because the second B lineage has not been detected since 2020.

For the full picture on flu vaccination this season, return to our complete guide to flu vaccines for 2026/27, or read about flu jab side effects and having the flu and Covid vaccines together.

This page is for general information and does not replace an individual clinical assessment. Flu vaccines are prescription-only medicines. In an emergency, call 999.

Sources: UKHSA Green Book, chapter 19, Influenza, 25 August 2026; JCVI advice on influenza vaccines for 2026 to 2027; UKHSA, influenza vaccines marketed in the UK for 2026 to 2027 (20 July 2026); Scottish Government, SGHD/CMO(2026)05, Annexes C and D; Summaries of Product Characteristics for the cell-based and adjuvanted trivalent influenza vaccines (electronic medicines compendium).