In the forecast for the period between April 28 and May 04, SPAIC said that in the region of Trás-os-Montes and Alto Douro, pollen will be at a high to very high level, predominating the pollen of pine, birch, olive, cork oak and oak trees and also of grass.

The bulletin indicates that, for the region of Entre Douro and Minho, the predicted levels will also be raised to very high, as well as for the region of Beira Litoral, where the pollen of the olive trees, cork oak and oaks and grasses, parity and nettle will predominate.

According to SPAIC, in Beira Interior, pollen will present a very high level and in the atmosphere will prevail the pollen of pine, olive, cork oak and oak trees and grasses, nettle and sorrel.

As for the region of Lisbon and Setúbal, the forecast also points to a very high level, which will also be across the Alentejo and the Algarve.

In the south of the country, the pollen of cypress, pine, olive, cork oak and oak trees and grasses, nettle will predominate.

For Madeira, the forecast indicates a low to moderate level of concentration in the atmosphere, with emphasis on the pollen of the pine tree and also for grasses and parity, and the Azores will present a low level, predominating the pollen of the pine, cypress and or cryptomeria trees and also of the parity and nettle herbs.

According to SPAIC, the high concentration poses a risk to people who are allergic to pollen and who may develop symptoms of allergic rhinitis such as sneezing, tearing and eye complaints and eventually developing asthma.

Practical recommendations in the face of the high concentrations of pollen are for allergic people to wear sunglasses when going outside, to travel by car with the windows closed, to keep the clothes you wore that day away from the bedroom, to avoid ventilating the house at times of higher concentration of pollen in the air, as early in the morning, and to wear a full helmet, if you are a motorcyclist.

The large peaks of concentration occur between mid-March and June, but high levels can also arise in the fall.

In 2002, the Portuguese Aerobiology Network (RPA) was created, a free service provided by SPAIC that monitors, nationally and continuously, pollen grains and fungal spores present in the atmosphere with potential negative repercussions on human health.

The RPA results from the collaboration between researchers and professors from the Universities of Évora, Madeira and Azores and immunoallergologists from various hospitals throughout the country.

Currently, RPA consists of nine stations or monitoring centers located in Porto, Vila Real, Coimbra, Castelo Branco, Lisbon, Évora, Faro, Funchal and Ponta Delgada.