How is asthma affected by the flu?

What is asthma?

Asthma is a very common condition that affects the airways of the lungs, causing irritation and inflammation which leads to symptoms such as breathlessness and tightness in the chest. In the case of a bad asthma attack, the airways can close up, leading to a life-threatening shortness of breath. Bad flare-ups of asthma symptoms are caused by triggers such as allergens, exercise, and some illnesses.

Asthma can generally be managed with the correct use of inhalers (usually a combination of preventers, that reduce inflammation and irritation in the lungs, and relievers, that soothe asthmatic symptoms by re-opening your airways).

What is flu?

Flu, or influenza, is a viral infection often confused with the common cold. Flu symptoms include a fever, headaches, aches and pains, coughing, sneezing and tiredness. Though flu can be caught at any time of year, it is especially common during winter. Read our article on flu symptoms to learn more.

As flu is a viral infection, it cannot be treated with antibiotics. However, most people will find that their symptoms pass within a week, provided they get lots of bed rest, stay warm, and drink plenty of water. Many people also treat their symptoms with over-the-counter painkillers and anti-inflammatories such as paracetamol and ibuprofen. It is also possible to get a prescription for the medicine Tamiflu, a tablet taken to either prevent contracting flu, or to shorten flu symptoms by up to a day.

If you are in a risk group for flu (i.e. if you are over 65, pregnant or have a weakened immune system or certain chronic health conditions) then you are entitled to a free flu vaccine on the NHS.

How is asthma affected by flu?

While it is not the case that people who suffer from asthma are more susceptible to catching flu, the symptoms of flu can make asthma worse in many cases. For 90% of people, viruses (such as flu) act as asthma triggers, setting off a bad flare-up of symptoms.

The reason for this is that asthma is characterised by the inflammation and sensitivity of the airways. Flu can often worsen these symptoms, as the virus can also affect the airways in the lungs and make them more irritated and inflamed - a common symptom of flu is a cough. In combination with asthma, flu can sometimes lead to more serious conditions such as pneumonia and bronchitis.

I have asthma. What should I do to protect myself against flu?

It could be that if you catch flu, your asthma symptoms will worsen. However, there are some things you can do to protect yourself.

The first, and most important, is to make sure you are managing your asthma correctly. This involves making sure of the following:

• You are using the right asthma medicines, in the correct dosages.
• You are using your inhaler (and your aero chamber or spacer) correctly.
• You have a personalised asthma action plan, detailing the nature of your condition, which helps you to stay on top of your symptoms (you are 4 times less likely to be admitted to hospital due to asthma complications if you have an asthma action plan).

Many people who suffer from asthma are not using the correct medicines to keep their symptoms under control. It is also very common for people to use their preventer inhaler incorrectly, or even avoid using it altogether. This means that their lungs can become easily inflamed and irritated - if they then catch flu, these symptoms will be worsened. Even those people who just use a reliever inhaler can be at risk if they are not using their inhaler properly.

Good asthma management involves:

•  Checking with a doctor, nurse, or pharmacist that you are using your inhaler correctly. You can also watch our video on correct inhaler technique here.
• Making sure you use your preventer inhaler if you have been prescribed one - even if you feel completely well, you should still use your preventer until your doctor instructs you otherwise.
• Visiting your doctor if your asthma symptoms are not going away, and/or if you are using your reliever more than 3 times a week.
• Keeping your asthma action plan up-to-date and reading through it regularly. You can download your own from Asthma UK.
• Being aware of triggers that might cause a flare-up in your symptoms and avoiding them.

If you follow the guidelines above, you can significantly reduce your chances of being badly affected by flu.

Do I need to get the flu vaccine?

People with asthma are more likely to need to the flu vaccine than people who don’t have asthma. However, Asthma UK states not everyone suffering from asthma needs the vaccine and that, if you are concerned about flu, you should visit your GP or nurse for advice. Typically, asthmatic people who will need the vaccine are:

• those using steroid preventer inhalers or taking steroid tablets
• those who have been admitted to hospital due to an asthma attack
• those who suffer from other conditions that put them at risk

Asthma sufferers who, for instance, only occasionally use their reliever inhaler and are not generally troubled by symptoms or other ill health should not need the flu vaccine.

How else can I avoid the flu?

Flu is spread by the coughs and sneezes of an infected person. As such, there are some precautions you can take to avoid getting the flu. These include:

• avoiding close contact with family or friends who have the flu
• washing your hands with soap and warm water regularly (to kill any droplets of the virus that may have gotten onto your skin)
• keeping surfaces and shared utensils or crockery clean

If you do get the flu and find that your asthma symptoms are getting worse, you should visit your doctor.

For more information on managing your asthma, visit our asthma clinic. 

While it is not the case that people who have asthma are more susceptible to catching flu, the symptoms of flu can make asthma worse in many cases.