What is Flu?
Seasonal Influenza (Flu) is an unpredictable but recurrent pressure on society every winter. Vaccination helps to provide the best protection. Flu is an acute viral infection of the respiratory tract and is spread easily by droplets, aerosol, or through direct contact with the respiratory secretions of someone with the infection. Even people with mild or no symptoms can infect others.
For healthy individuals, the virus causes an unpleasant but normally self-limiting disease with recovery usually within two to seven days. Common symptoms include:
- Sudden onset of fever, chills, headache, muscle and joint pain and extreme fatigue
- Dry cough, sore throat and stuffy nose
- In young children, gastrointestinal symptoms such as vomiting and diarrhoea may occur
Because of the changing nature of flu viruses, the World Health Organization (WHO) monitors their epidemiology throughout the world.
Each year WHO makes recommendations about the strains of influenza A and B which are predicted to be circulating in the forthcoming winter, based on information about the circulating viruses and epidemiological data at that time. These strains are then included in the vaccine developed that year.
There are two types of vaccine, a live attenuated vaccine given via nasal spray and an inactivated virus given via injection.
Mismatches between the components in the vaccine and circulating viruses do occur from time to time. This explains why the overall effectiveness of the vaccine can vary from year to year.
Who should have the flu vaccine?
The NHS vaccination programme for the 2020/21 flu season has been extended to include more groups than in previous years. As COVID-19 is likely to be circulating at the same time as flu, protecting individuals at high risk of influenza (who are also most vulnerable to hospitalisation as a result of COVID-19) is hugely important.
The vaccine is offered free of charge on the NHS to anyone with a serious long-term health condition including:
- Chronic (long-term) respiratory diseases, such as severe asthma
- Chronic obstructive pulmonary disease (COPD), or bronchitis
- Chronic heart disease, such as heart failure
- Chronic kidney disease at stage three, four or five
- Chronic liver disease
- Chronic neurological disease, such as Parkinson’s disease or motor neurone disease
- Learning disability
- Problems with the spleen – for example, sickle cell disease or if the spleen has been removed or is not working properly
- A weakened immune system due to disease (such as HIV and AIDS), or treatment (such as cancer treatment)
- Severe obesity (BMI >40)
Other groups identified at higher risk and eligible for the vaccine on the NHS this year include:
- Those aged 65 years and over (including those becoming age 65 years by 31 March 2021)
- Those aged six months to under 65 years in clinical risk groups
- All pregnant women (including those who become pregnant during flu season)
- All children aged two to eleven (but not twelve years or older) on 31 August 2020
- Those in long-stay residential care homes or other long-stay care facilities
- Those who are in receipt of a carer’s allowance, or who are the main carer of an older or disabled person
- Household contacts of those on the NHS Shielded Patient list or of immunocompromised individuals
- Health and social care staff
Following prioritisation of other eligible groups and subject to sufficient flu vaccine supplies being available, the NHS programme may be further extended in November and December this year. It is possible the flu vaccine may also be offered to individuals between 50-64 years of age
It is important to note that everyone is susceptible to flu and if you do not fall within the above categories it is reasonable and worthwhile seeking vaccination through your local pharmacy or an independent provider.
Common misconceptions about the virus
‘The vaccine can give you flu’
This is untrue. It is most likely that any flu-like symptoms experienced by people who have just had the vaccine are caused by either:
- One of many other circulating viruses that can produce flu-like symptoms
- Having contracted flu infection in the two weeks following vaccination before the immune system has had sufficient time to develop an immune response to the vaccine
- The body’s immune system responding to the vaccine
‘The vaccine doesn’t work’
The vaccine is usually between 30-60% effective depending on the age and health of the person receiving it and upon how well the circulating flu strains match the composition of the vaccine.
Even when flu is not completely prevented by vaccination, those who have received the vaccine may have some protection that could reduce the severity of their symptoms
‘It doesn’t affect healthy people’
Although typically the elderly, very young and people with underlying medical conditions are at greater risk of suffering from severe illness, previously healthy people and the young can also develop severe complications from flu.
In 2009/10 and 2010/11, up to one third of deaths from flu were in people considered healthy. Many cases of severe illness were in those aged under 65 years.
Although a good diet and a healthy lifestyle is always to be encouraged, this alone will not prevent flu. Vaccination is the best option for protecting yourself, your family and vulnerable patients from the virus.
In summary, the flu vaccine, whilst not 100% effective, is still the best way to reduce the risk of getting flu and spreading it to friends and relatives who may be more susceptible to serious complications of flu such as pneumonia, encephalitis and even premature mortality.
There are very few individuals for whom flu vaccination is unsafe or unsuitable and given that we are all susceptible to flu, now more than ever, is a very important time to take whatever steps we can to protect our own health as well as society’s.
Dr. Sidra Malik BMBS MRCGP DRCOG DFSRH
10th September 2020