Talaia*, M.A.R., Vieira da Cruz**, A.A., Saraiva**, M.A.C. and Manso Orgaz*,M.D.

*Physics Department, University of Aveiro, Aveiro, Portugal **Service of Medicine Intern and Service of Pneumologia, Hospital Infante D. Pedro, Aveiro, Portugal

The influence of weather and climate on infectious diseases is a very complex problem. Infectious diseases can be affected by several meteorological factors, namely the resistance of the human body to infection and the case of spread of an infection. The assumption that the meteorologically induced seasonal fluctuations, in the general resistance of the population, may play a more important part, in the epidemiology of diseases, than is generally assumed. For example, influenza virus and pneumonia may be called winter diseases. Thus winter months with very low humidities and little air movement in heated buildings are favourable for the transmission of infections respiratory diseases. In this paper, our aim attention is to relate, the beginning of pneumonia and influenza “attacks” in the services of urgency of the Hospital of Aveiro with meteorological factors. The risk group (age and sex) are studied. The Aveiro region, more concretely Aveiro lagoon, is located in the central region of Portugal. It has own characteristics for being windy and humid and it can be considered temperate by the influence of the sea. A statistical study was considered. We used the medical records and the database of meteorological factors (1999-2001). The investigation shows that the air temperature seems to be an important factor to the appearance of the disease that leads the patients to the medical urgencies. We observed biometeorological relationships. The study shows that the cooling weather seems to be determinant in the eruption of the diseases. In fact, the diseases occur when the outside temperature of the air is low. The obtained analysis allows to conclude that some meteorological factors have correlation with the occurrences of the disease and to allow improving the work in the urgency services in the requested periods. Last, the most vulnerable persons to infectious diseases should adopt precaution measures before the beginning of the favourable period of infection.