At Risk Groups

Influenza A&B and parainfluenza have been linked with COPD exacerbations and often multiple viruses can be detected. The proportion of exacerbations related to isolation of influenza virus differs between studies and is probably influenced by the number of COPD patients that receive influenza vaccination. Influenza infections are a cause of excess morbidity and mortality in COPD and may affect the progression of the disease. Vaccination remains the gold standard for prevention of influenza in at-risk subjects including patients with chronic diseases such as COPD.

Studies investigating the excess mortality associated with the flu season suggest that approximately 35–50% are due to cardiovascular disease.³

A flu pandemic has highlighted that people with diabetes suffer from more severe influenza than those with no underlying condition.⁴

Diabetes triples the risk of hospitalisation after influenza A (H1N1)p and quadruples the risk of ICU admission once hospitalised.⁵

Patients with diabetes are at higher risk of severe disease and complications such as hospitalization or death as a result of developing influenza. Actually, patients with diabetes are three times more likely to die from flu complications than those without diabetes.⁶

People with diabetes are more likely to die or be admitted to hospital as a result of influenza than healthy individuals.⁷

Immunosuppression (e.g. from chemotherapy, HIV, asplenia, spleen dysfunction or long-term steroid therapy) puts patients at risk of succumbing to flu complications if they contract the disease.¹

High risk groups include those with neurological conditions e.g. people who have had a stroke, transient ischaemic attack (TIA), cerebral palsy and other diseases of the neuromuscular system.¹

The PHE Green Book and National flu immunisation programme recommends that pregnant women are offered the flu vaccine, at any stage of their pregnancy.^1,9 A study review concluded that inactivated flu vaccine can be administered during all trimesters of pregnancy, with no increased risk to the mother or the unborn child.¹

Pregnant women are particularly vulnerable to severe complications of flu.¹ There is also evidence that flu during pregnancy may be associated with premature birth and smaller birth size and weight, and that the flu vaccine may reduce this risk.¹ Another benefit of antenatal flu immunisation is that it confers passive immunity to newborns during the first few months of life.¹

For 2021/22, the National flu immunisation programme has set a goal of at least 55% uptake of the flu vaccine in pregnant women, with the ultimate aim of at least 75% uptake.⁹

The risk of hospitalisation for pneumonia and flu during the flu season is at least 5 times higher in those aged ≥65 years compared with those <65 years.¹⁰

In a study of the burden of influenza in England by age and clinical risk group, the vast majority of the annual deaths occurred in the 65+ age group, particularly those with underlying co-morbidities (72% of total).¹¹

In 2021-22, children eligible for the influenza vaccine include: all children aged 2 to 15 on 31 August 2021, those aged 6 months to 2 years in clinical risk groups.⁹

From 2015, the PHE Green Book has recommended that adults with a Body Mass Index ≥40 kg/m² be offered the flu vaccination.¹ In many cases, these patients will also be at risk due to other conditions they contract due to complications of obesity.

The PHE Green Book recommends that healthcare workers who are directly involved in patient care should have a flu vaccine every year.¹ Flu immunisation of health and social care workers with direct patient contact is likely to reduce transmission of infection to vulnerable patients, including those with impaired immunity that may not respond well to a flu vaccine.

Frontline healthcare workers are more likely to be exposed to the flu virus, especially during winter months. Estimates suggest that up to one in four healthcare workers may become infected with flu during a mild flu season.¹⁴ This is a much higher incidence than would be expected in the general population.¹⁴

Flu immunisation should be offered by NHS organisations to all employees directly involved in patient care, as part of their policy for preventing flu transmission to protect patients, staff and visitors.⁹

NHS England has published a CQUIN covering 2017/18 and 2018/19 which includes an indicator to improve the uptake of flu vaccinations for frontline healthcare workers. The ambition is for providers to achieve uptake of flu vaccinations by frontline healthcare staff of 75%.⁹

Examples of staff who may be directly involved with patient care include: clinicians, midwives and nurses, paramedics and ambulance drivers, occupational therapists, physiotherapists, radiographers, GPs, practice nurses, district nurses, health visitor social care staff in care settings, and pharmacists.

Flu can spread rapidly from person to person when there are many people living at close quarters, and this likely to lead to significant morbidity and mortality.¹ This does not include university halls of residence.

Immunisation of people caring for elderly or disabled relatives or friends helps protect the people they are caring for, and protects the carers from falling ill and being unable to fulfil their care duties.¹