Why a common cold can trigger respiratory crises in asthma and COPD sufferers
Nasal cell response explains why rhinovirus affects some mildly while others face hospitalisation, say Yale researchers.
- 16 March 2026
- 3 min read
- by Priya Joi
At a glance
- Rhinoviruses that cause the common cold are the leading trigger of asthma attacks and hospitalisations in people with asthma and chronic obstructive pulmonary disease (COPD).
- New research from Yale suggests severe illness is driven not by the virus itself, but by a weakened immune response in nasal cells, which normally send early warning signals to control infection.
- Understanding how this frontline defence fails could help scientists to develop treatments to prevent dangerous respiratory crises triggered by common cold infections.
The coughs and sniffles caused by the common cold virus are a familiar soundtrack to the winter season. In most people they trigger an annoying but benign sickness, however in some cases the virus can cause deadly respiratory illness.
For people with asthma and chronic obstructive pulmonary disease (COPD), the rhinoviruses that cause the common cold are the main cause of asthma attacks and hospitalisations, causing symptoms like wheezing, shortness of breath and a persistent cough, which can escalate into a full-blown respiratory crisis.
Until now, it wasn’t clear why the same virus causes only mild symptoms in some people but severe breathing problems in others.
In people with asthma or COPD, the inflammation that is often present in the airways muffles the message, delaying the immune response. This allows the rhinovirus to run rampant and trigger far worse infection.
A Yale research team publishing in Cell Press Blue have now shown that the answer lies not with the rhinovirus itself but in the body’s response to the virus.
The researchers found that the first-line defences in nasal tissue are much more important than initially thought.
Cells inside our nose have built-in defence mechanisms against infections that send a warning signal to the immune system to immediately dampen the virus, causing only mild symptoms.
However, in people with asthma or COPD, the inflammation that is often present in the airways muffles the message, delaying the immune response. This allows the rhinovirus to run rampant and trigger far worse infection.
Cold comfort
In the study, the researchers experimented with infecting lab-grown nasal tissues with rhinovirus (‘rhino’ is derived from the Greek word for nose). These human-like nasal cells could be grown into organoids in the lab that were able to develop cilia and produce mucus, replicating the inside of the nose and lungs.
Normally, nasal cells produce an immune defence called an ‘interferon’ response, which subdues the rhinovirus so that only about 2% of nasal cells become infected.
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However, even the uninfected cells responded by activating the interferon antiviral defences that warn neighbouring cells of an infection.
When the researchers blocked the warning signals, they observed a dangerous cascade of reactions. The delay in signalling led to excessive mucus production and inflammation, mimicking the responses seen in asthma and COPD attacks.
Signal blocked
The explanation seems to be two-fold.
As Dr Ellen Foxman, a professor of immunobiology at Yale School of Medicine and lead author on the study, explains: “In our model, we inhibited the response with a drug, but it’s known that in people with chronic airway diseases, the interferon response is lower than in a healthy person. That’s the ‘why’ we just don’t know yet. It’s our next step.”
Second, epithelial cells from airways that are chronically exposed to inflammation, as in asthma and COPD, might be desensitised to a warning signal from the nasal cells. In other words, it takes them longer to realise there’s an infection – the virus can double its numbers by the time the immune system responds.
The authors say that by elucidating the signalling pathway that can be disrupted when that first line of defence fails, the research offers targets for drugs to prevent dangerous reactions to rhinovirus.
