The flu season is on its way; new study investigates how colds trigger Asthma

The flu season is on its way; new study investigates how colds trigger Asthma

People who suffer with asthma often find that when they have a cold they are more susceptible to severe asthma symptoms and even asthma attacks. A recent study by researchers at the Imperial College London has looked at the specific reasons why a cold can increase asthma problems so dramatically. In the UK 5.5 million people are being treated for asthma, they currently use inhalers to manage their condition however in instances when the body is fighting a virus such as a cold it can cause severe flare ups.

In a simple, broad analysis, it was found that asthma sufferers immune systems over produce chemicals when a cold is present. This chemical in turn causes issues with the lining of lungs, leading to inflammation and an increase in asthma symptoms. The aim of the research was to identify how exactly this process happens and if there is a way to prevent or alleviate the situation.

The laboratory study included both human and animal research that investigated the protein interleukin-25 (IL-25). When an individual is suffering from a viral infection such as the common cold, asthma symptoms worsen and in extreme circumstances it can lead to an attack. The protein IL-25 presents itself when a cold is present and it affects the body by causing inflammation and the autoimmune process.

The study showed that people who suffered from asthma had an increased rate in IL-25, potentially suggesting why a common cold can lead to problematic issues regarding asthmatics.

In the study the team exposed patients with the rhinovirus (common cold). In the first instance they tested on both patients with and without asthma however after initial exposure neither patient showed an increase in IL-25 levels. Up to 10 days after exposure there was a change between the groups of patients. 61% of those with asthma (17 of 28) displayed a significant increase in IL-25 levels. In patients without asthma there was a slight increase in IL-25 levels, however these levels represented a normal amount of IL-25.

When the results were further examined the direct relation between IL-25 and an inflammatory response was identified. To counter the inflammation the study team used an IL-25 blocking antibody which blocked the inflammatory response in the lungs that happened due to the exposure of the rhinovirus infection.

The research in the study found that using an IL-25 blocking medication could potentially be a promising way to reduce symptoms in asthma suffers when they have a cold or illness. The research is only in the beginning stages of development so further research must be done to make an effective blocking treatment. There still needs to be research into asthma, especially into how symptoms can become severe due to other external circumstances.

Dr Samantha Walker, Asthma UK, who funded the research, said “Asthma still remains a relative mystery and the millions of people with asthma need more studies like this to bring us one step closer to new treatments”.

[1] “How a simple cold can set off a deadly asthma attack: Scientists discover chemical can send the immune system into overdrive”, Fiona Macrae, Mail Online,, 2014
[2] “Study finds clue to why colds trigger asthma”, ,NHS choices, 2014