What is asthma?
Asthma is a common life-long disease that is affecting more and more people all over the world. In asthma, the airways become inflamed (swollen) and narrow, and breathing becomes difficult. Asthma can make you cough, you may feel as if your chest is tightening and your breathing may become noisy (wheeze).
What do infections have to do with asthma?
Respiratory infections can cause problems for people with asthma by causing exacerbations.
What is an exacerbation?
When symptoms of any disease occur more frequently and are worse than normal it is called an exacerbation. In people with asthma, signs of an exacerbation are increased breathlessness, coughing and chest tightening.
What causes an exacerbation?
Exacerbations can be caused by direct contact with allergens such as animal fur, bee stings and pollen, but most exacerbations are caused by infections. Infections can cause severe asthma symptoms that develop very quickly. This is known as an “acute” exacerbation and action must be taken immediately to get the correct treatment.
Which respiratory viruses cause asthma exacerbations?
The most common viruses are human rhinoviruses, which cause the common cold. Other viruses that can cause exacerbations include coronaviruses, influenza (flu), parainfluenza viruses and respiratory syncytial virus (RSV).
Why do cold viruses trigger asthma exacerbations?
Many scientists have found a link between the common cold and worsening asthma symptoms. If you have a common cold (caused by a rhinoviral infection), the virus will usually be present in your upper airways as well as deep inside your lungs. People with asthma may have cold symptoms for longer because it takes time to recover from an exacerbation. However, they may not necessarily have colds more often.
How are infections spread?
The commonest way to pick up an infection is by coming into close or direct contact with someone who already has an infection. Viruses survive best in crowds. A wide and quick spread of rhinoviruses is often seen when children return to school after the summer break.
How can I tell how severe my exacerbation is?
As well as experiencing more symptoms during an exacerbation, a peak flow meter can also help confirm whether your condition is getting worse. A peak flow meter can show how bad your exacerbation is by measuring the speed at which air can pass through the airways. When the airways are inflamed, it is harder to breathe out and peak flow readings will be lower than usual. This is because inflammation will be partly blocking the airways. Exacerbations can be spotted at an early stage if there is a drop in morning peak flow of more than 25%.
Short-acting bronchodilators should be used more often and if this does not help contact your doctor. If your peak flow values drop by more than 50% you should seek medical advice immediately. If you have asthma and you have an exacerbation, you may need to step up your treatment according to your action plan.
How can I manage my asthma at home?
The best way to prevent exacerbations is to take your maintenance therapy regularly and to have good asthma control. The better you can control your asthma, the less irritated your airways will be when you have an infection. This may be because your airways are less swollen. Mild symptoms can be relieved with the use of an inhaler that relaxes the airways (bronchodilator).
More severe exacerbations require more intensive treatment and you should discuss an action plan with your doctor, who may ask you to take a lung function test. One of the things that this will show is the amount of air you can force out of your lungs in one second (FEV1). This information will help your doctor to decide what treatment will help you to manage your condition more effectively.
This information was compiled by ERS Respiratory Infections expert, Dr Gernot Rohde MD
GRACE is an EU 6th Framework Programme Network of Excellence to combat resistance
to antibiotics in the community.This project aims to combine the activities of physicians and
scientists from many institutions in 14 European countries to combat antibiotic resistance in community-acquired lower respiratory tract infections.