Doctoral Thesis
DOI
10.11606/T.5.2016.tde-03022016-115428
Document
Author
Full name
Rosângela Peregrina Sanches
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2015
Supervisor
Committee
Azevedo Neto, Raymundo Soares de
Ferreira, Cláudia Pio
Ortega, Neli Regina de Siqueira
Yang, Hyun Mo
Title in Portuguese
Análise do número de reprodutibilidade basal na fase inicial de doenças causadas por vetores
Keywords in Portuguese
Dengue
Estudocomparativo
Funções verossimilhança
Modelos matemáticos
Modelos teóricos
Número básico de reprodução
Abstract in Portuguese
Title in English
Analysis of the basic reproduction number from the initial growth phase of the outbreak in diseases caused by vectors
Keywords in English
Basic reproduction number
Comparative study
Dengue
lLkelihood functions
Mathematical models
Models theoretical
Abstract in English
The basic reproduction number,R_0, is defined as the expected number of secondary cases of a disease produced by a single infection in a susceptible population. If R_0 < 1 the disease cannot establish in the population, and if R_0 > 1 we expect the disease spread in the population. The value of R_0 can be estimated in several ways, for example, with the stability analysis of a compartmental model, through the matrix of next generation, using the final phase of an epidemic, etc. In this work we studied methods for estimating R_0 from the initial growth phase of the outbreak, without assuming exponential growth of cases, which is suggested in most studies. We used the methods proposed by Nishiura, Ross-Macdonald and White and Pagano. The objective of this work was to compare these techniques and to evaluate how these technique estimate the value of the basic reproduction number, applying them to diseases caused by vectors. In this particular case we used data of dengue. We used data from the city of Ribeirão Preto in the periods of 2009-2010 and 2010-2011, in both cases the city had an outbreak. The results obtained by the three methods are numerically different. We can conclude that all methods are correct in the sense that dengue will spread in the city studied, what is true for the cases studied, although they are numerically different. Weekly analysis of the data show that the estimated values have a same pattern over time