People have been cautioned that pollen can cause death.

When the pollen count climbs, people with asthma are at risk of fatal attacks, with high levels expected this weekend.

More than three million individuals in the UK have lung disorders including asthma or chronic obstructive pulmonary disease (COPD) and are at risk of attacks or flare-ups, according to Asthma and Lung UK.

From Friday, high pollen levels are expected in much of England and Wales, with medium levels in other parts of the UK.

Symptoms such as a runny nose and itchy eyes are common in those who suffer from hay fever.

However, more than half of asthmatics (59%) report pollen can cause symptoms including tightness in the chest, wheezing, and shortness of breath.

According to the charity’s research, a quarter of persons with COPD feel the same way.

Allergies can cause airways to constrict and sticky mucus to build up, making breathing difficult.

Asthma episodes can be fatal; in the United Kingdom, four people die from it every day.

“When pollen levels are at their peak, this can be devastating for patients with lung disorders like asthma who can suffer serious symptoms and have life-threatening attacks,” said Dr Andy Whittamore, clinical lead for Asthma and Lung UK.

People may struggle to breathe as a result of these attacks, which can be dangerous.