Top Tips: Optimising Flu Vaccination for 2022–2023

Dr Toni Hazell Examines UK Health Security Agency Guidance to Provide 10 Top Tips on Effective Delivery of the 2022–2023 Flu Vaccination Programme in Primary Care

Influenza, usually shortened to flu, is a respiratory illness caused by one of several influenza viruses. The most common, virulent strain is influenza A; in general, the B and C strains cause less severe illness.¹ Identification of the strain is not usually of clinical importance.

For most people, flu is a self-limiting illness¹ that can be managed with rest, fluids, and antipyretics, but for some it can be more severe, with complications including pneumonia, myocarditis, Guillain–Barré syndrome, and death.² Pregnant women in their third trimester are at particular risk of complications from flu, as the illness can cause premature labour and low birth weight.^2,3

Vaccination against flu is a key way to reduce morbidity and mortality. This article offers 10 top tips for the successful delivery of the 2022–2023 flu vaccination programme, drawing on guidance issued by the UK Health Security Agency.

1. Identify Adults Entitled to a Flu Vaccine through the NHS

For many years, the cohort eligible for flu vaccination through the NHS stayed fairly stable, and consisted of all adults aged 65 years and older, some children (as part of a phased extension of the programme), health and social care workers, carers, and people aged 6 months–65 years with comorbidities as listed in Table 1.³ In the 2020–2021 and 2021–2022 seasons, because of the COVID-19 pandemic, this cohort was extended to include all adults aged 50–64 years.⁴ In April 2022, it was announced that vaccination by age alone would be offered only to those aged 65 years and older,^5,6 reverting to pre-pandemic criteria, but this decision was reversed in July.^5,7 Therefore, the NHS is currently offering flu vaccination to all those aged 50 years and older, including those who will turn 50 years old by 31 March 2023.^5,7

Table 1: Clinical Risk Groups that Should Receive Influenza Vaccination³

2. Understand How Children Are Usually Vaccinated Against Flu

School-age children are vaccinated against flu at school. This year, flu vaccination is being offered to all school children up to year 9, and to those in years 10 and 11 depending on vaccine availability.^5,7 All younger children can be vaccinated against flu at a GP surgery if they will be at least 2 years old on 31 August 2022, and children with a comorbidity can be vaccinated from the age of 6 months.⁵ If a school-age child misses their vaccination, they can usually attend a community catch-up clinic run by the school nursing team⁸ —these clinics will also vaccinate home-educated children in the eligible age groups.⁹

3. Be Aware of the Rationale Behind Different Flu Vaccines

Those GPs of a similar vintage to the author may look back fondly on the days when everyone seemed to get the same vaccine; it was much easier to reach for the same shelf in the fridge every time. There are, however, sound clinical reasons for the variety of vaccines available today. As we get older, we are affected by immunosenescence, a process of immune system deterioration characterised by changes such as an altered balance of pro- and anti-inflammatory cytokines and reduced phagocytic capacity.¹⁰ Vaccines containing an adjuvant are more likely to overcome immunosenescence,^3,11,12 and are therefore offered to those aged 65 years and older.³ Conversely, the live activated influenza vaccine (LAIV) gives better protection for children,³ and is delivered by nasal spray rather than a painful needle,¹³ and is therefore the first-line option for those aged 2–18 years.^3,13

4. Remember that some Children Cannot Have the Live Flu Vaccine

Children who are clinically severely immunocompromised cannot be vaccinated with the LAIV;^3,13 this is because of the risk that they may develop flu. This includes children with diseases such as leukaemia, lymphoma, untreated HIV, and cellular immune deficiencies.³ However, those with stable HIV on antiretrovirals can be given the LAIV.³ Immunisation with the LAIV should also be avoided in adolescents who are pregnant or breastfeeding,^14,15 and anyone receiving salicylate therapy.³ Immunosuppression that precludes administration of the LAIV can also be due to treatment—for example, caused by drugs given after a transplant or high-dose corticosteroids.³ Topical, inhaled, and low-dose systemic corticosteroids are not considered contraindications to the LAIV.³

The Joint Committee on Vaccination and Immunisation has also advised that children with asthma on inhaled corticosteroids may be given the LAIV, irrespective of their dose, but that it is not recommended for those who have experienced an exacerbation of symptoms in the previous 72 hours.³ In such cases, a suitable inactivated vaccine is recommended.³ Children who require regular oral steroids to control their asthma should only be given the LAIV on the advice of their specialist.³

Children aged under 9 years who are in a clinical risk group and have not previously been vaccinated for flu will also require a second dose of vaccine, to be administered at least 4 weeks after the first.³

5. Know Which Flu Vaccines Are Suitable for Whom

Flu vaccination clinics are busy places, often with hundreds of vaccines being administered in a single morning. Easily accessible information, such as posters on vaccine fridges, can help to ensure that everyone administering vaccines knows which vaccine is suitable for which patients. For the 2022–2023 vaccination season, adults aged 65 years and older should be offered either the adjuvanted quadrivalent inactivated influenza vaccine (aQIV) or the quadrivalent recombinant influenza vaccine (QIVr).^16,17 As in previous years, the aQIV can be offered ‘off-label’ to those who will turn 65 years of age before 31 March 2023, unless they have been admitted to intensive care because of an egg allergy.¹⁷ In theory, adults aged 65 years and older could also be given the high-dose quadrivalent inactivated influenza vaccine (QIV-HD), but it is not currently available in the UK.¹⁷

At-risk adults aged less than 65 years, including pregnant women, should be offered the QIVr or the quadrivalent influenza cell-culture vaccine (QIVc)—if neither of these is available, they can be offered the quadrivalent influenza egg-culture vaccine (QIVe), unless they are allergic to egg and have had an intensive therapy unit admission as a result of this allergy.^16,17

Adults aged 50–64 years who are not in a clinical risk group should be offered the QIVe principally, as it is recommended that the most effective vaccines (QIVr and QIVc) are first offered to more vulnerable cohorts.⁵ The QIVr and QIVc can also be offered in situations where this does not divert stock from other groups.⁵ Children who are aged from 6 months–2 years old and require vaccination because of a comorbidity should also be offered the QIVe, unless they are allergic to egg.^3,18

6. Reassure Patients that Egg Allergy Does Not Always Rule Out Flu Vaccination in Primary Care

Some flu vaccines are cultured in a solution containing egg, leading to concern among people who are allergic to eggs. Any setting offering vaccination should have the facilities to treat anaphylaxis,¹⁹ which is an unpredictable event. However, patients with an egg allergy should be reassured that they can usually be vaccinated with their cohort, be this at the GP surgery or at school.³ The QIVc and the QIVr are egg free,²⁰ and most of the QIVe and LAIV vaccines available have very low amounts of ovalbumin (see Table 2).²⁰

Table 2: All Influenza Vaccines Marketed in the UK for the 2022–2023 Season²⁰

The Green Book notes that adult patients can be immunised in primary care using an inactivated flu vaccine with an ovalbumin content of less than 0.12 mcg/ml, equating to 0.06 mcg or less for a 0.5 ml dose.³ The exception to this recommendation is any patient that has been admitted to intensive care because of their allergy—this cohort should be referred to a specialist, with a view to vaccinating in hospital.³

Children who have needed admission to intensive care for an anaphylactic reaction to egg are also an exception. There are limited data for this cohort, and it is best if they receive the LAIV in hospital.³ In the extremely rare situation that a child has such a serious egg allergy and the LAIV is also contraindicated (see Tip 4, Remember that some children cannot have the live flu vaccine), they should be given an inactivated vaccine with an ovalbumin content of less than 0.12 mcg/ml.^3,20 Children aged under 2 years with an egg allergy can be offered the QIVc; however, this constitutes unlicensed use of the vaccine.¹⁶

7. Prepare for Evidence-based Discussions with People who Reject the LAIV on Religious Grounds

Pork-based gelatine is used as a stabiliser in the manufacturing process for the LAIV.^21,22 It is highly processed and broken down, with tests showing that no porcine DNA can be detected in the actual vaccine.^21,22 However, some people whose religion prohibits consumption of pork may be concerned about this. If the parent of a child who is due to receive the LAIV consults you about this, you can point them to information from the Vaccine Knowledge Project,²¹ the Muslim Council of Britain,²³ the Kashrus and Medicines Information Service,^21,24 and Public Health England.²² For those parents who will still not accept the vaccine, the QIVc can be offered if the child is aged 2 years or over.⁷

8. Be Clear that Children who Have Had the LAIV Do Not Generally Pose a Risk to Others

In recent years, several antivaccination campaigns have focused on the risk of those who have received a live vaccine ‘shedding’ the virus against which they have been vaccinated, thereby passing on the disease to those around them.²⁵ Patients may raise this as a concern if their child is due to receive the LAIV and they live with a family member who is immunocompromised. The Green Book notes that, in the United States (where the LAIV is used extensively), there have been no reported cases of illness or infection among immunocompromised contacts of those who have received the LAIV.³ However, it advises that it would be reasonable to consider an alternative, inactivated vaccine if close contact with a very severely immunocompromised person is unavoidable—for example, if a child is living with someone who is in isolation following a bone marrow transplant.³

9. Consider Delivering Other Vaccines at the Same Time

A flu vaccination clinic is the ideal setting in which to catch up on other vaccinations, such as for Streptococcus pneumoniae, shingles, or COVID-19. At the start of the COVID-19 vaccination effort, vaccinators were advised not to give flu and COVID-19 vaccines together; however, this is now considered safe.^26,27 Furthermore, non-live vaccines can usually be coadministered.³

The only exception to this rule is for those patients being given the Shingrix^®▼ (GlaxoSmithKline UK) shingles vaccine in conjunction with an adjuvanted flu vaccine, such as the aQIV.²⁸ The Green Book advises that, if possible, the vaccinations should be separated by at least 7 days, because there is an absence of data on this particular situation.²⁸ This exception does not apply to other brands of shingles vaccine, or for non-adjuvanted flu vaccines.²⁸ However, if rapid protection is needed, or if a 7-day gap will lead to the person being lost to follow up, the guidance notes that coadministration can be considered.²⁸

10. Think About Ways to Increase Vaccine Uptake

There are concerns that flu may be particularly serious in 2022–2023 because immunity is likely reduced as a result of 2 years of measures to reduce the spread of COVID-19.⁶ We have already seen the potential consequences of reduced immunity due to social distancing: reduced exposure to adenoviruses might have played a part in a recent outbreak of hepatitis among children that led to liver transplants and deaths.²⁹ The flu season in Australia, often a portent of what is to come in the UK, has also seen a higher-than-usual incidence of disease caused by influenza A, which is associated with more severe illness.³⁰ Therefore, it is even more important than usual that we try to maximise vaccine uptake.

Ways to do this include raising awareness among eligible groups (for example, discussing flu vaccination at antenatal clinics and when people attend pharmacies), using articles such as this to ‘myth bust’ concerns about issues like egg allergy and porcine gelatine in vaccines, and providing vaccinations in well-visited places, such as community or religious centres. The NICE guidance on increasing flu vaccination uptake has more detailed suggestions,³¹ and you may also want to consider the ‘presumptive ask’. By using presumptive language (for example, ‘It’s time for your flu vaccination; hold on while I get it from the fridge’, instead of ‘Would you like a flu vaccination?’), uptake can be increased.³² The patient or parent clearly still has the opportunity to withhold their consent or ask questions, but is prompted to accept the vaccine.

Summary

Vaccines save lives, and—with concerns about a more severe flu season than usual in 2022–2023—it is important that as many people as possible are vaccinated. Primary care teams need a thorough knowledge of who should be vaccinated and with which vaccine, and should make all possible efforts to increase vaccine uptake.

Dr Toni Hazell

Portfolio GP, Tottenham, London