Revista Egitania Sciencia - Volume 18 | ARTICLE

Title: APPLICATION OF DURATION MODELS TO GRIPNET DATA FOR ANALYSIS OF THE SPREAD OF INFLUENZA IN PORTUGAL FROM 2008 TO 2012

Author: Sónia Costa (soniacosta27@live.com.pt), Alcina Nunes (alcina@ipb.pt), Carlos Balsa (balsa@ipb.pt)

Publication: Revista Egitania Sciencia - Volume 18

Abstract:
Influenza affects millions of people worldwide, endangering human health with not only clinical but also economic consequences. Thus, it is important to know how it may evolve and the factors that can propel its spread, allowing the population in general and health facilities, in particular, to be prepared. Thus, this research project aims to analyse how influenczahas been propagated over time in Portugal by applying nonparametric duration models (Kaplan-Meier and Nelson-Aalen) to a cross-section database with annual data over a continuous period of eight years (2005-2012). The database was provided by Gripenet, an observatory that, with the support of volunteer participants, monitors the annual growth of the phenomenon of influenza. Results show that, for 50% of the participant population under review, infection occurs in December and January of each year. . Subdividing the sample reveals that women are less likely to contract the virus in the early days of analysis, getting around on foot and using public transport presents a riskfor contracting the virus that increases very slowly with time, smokers presents a probability 126 of infection that increases more rapidly over time and those living alone have an initial reduced risk of contagion.

Keywords: influenza, duration models, gripenet, Portugal




               INSTITUTO POLITÉCNICO DA GUARDA | Av. Dr. Francisco Sá Carneiro, 50 | 6300 - 559 Guarda | Tel.+351271220100 | Fax +351271222690