In a note published on its website, the DGS advises the most sensitive population such as the elderly, children, patients with chronic respiratory problems (asthma) and people with cardiovascular diseases to take extra health care such as staying inside buildings, preferably with the windows closed.

The health authority also advises the general population to limit physical activity outdoors, prolonged exertion and exposure to tobacco smoke, as well as contact with irritating products.

The Directorate-General for Health states that due “to the intrusion of an air mass from the deserts of North Africa, which carries suspended dust and crosses mainland Portugal, there will be increasing concentrations of naturally occurring inhalable particles in the air”.

In case of aggravation of symptoms, people should call the Health Line 24 (808 24 24 24).