Interpreting measures of tuberculosis transmission: a case study on the Portuguese population

BMC Infectious Diseases

M Gabriela M Gomes²  Raquel Duarte¹  Roberto FS Andrade³  Suani TR Pinho³  Paula Rodrigues⁴  Joao Sollari Lopes² 

[1] Instituto de Saúde Publica, Universidade do Porto, 4050-600 Porto, Portugal;Instituto Gulbenkian de Ciência, Apartado 14, 2781-901 Oeiras, Portugal;Instituto de Física, Universidade Federal da Bahia, Campus Universitário de Ondina, 40210-340 Salvador, Brazil;Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal

关键词: Tuberculosis epidemiology;    Transmission dynamics;    Sojourn times;    Heterogeneity;   

Others  :  1127514
DOI  :  10.1186/1471-2334-14-340

 received in 2013-12-09, accepted in 2014-06-09,  发布年份 2014

【 摘 要 】

Background

Tuberculosis remains a high burden for Human society despite considerable investments in its control. Unique features in the history of infection and transmission dynamics of tuberculosis pose serious limitations on the direct interpretation of surveillance data and call for models that incorporate latent processes and simulate specific interventions.

Methods

A transmission model was adjusted to the dataset of active tuberculosis cases reported in Portugal between 2002 and 2009. We estimated key transmission parameters from the data (i.e. time to diagnosis, treatment length, default proportion, proportion of pulmonary TB cases). Using the adjusted model to the Portuguese case, we estimated the total burden of tuberculosis in Portugal. We further performed sensitivity analysis to heterogeneities in susceptibility to infection and exposure intensity.

Results

We calculated a mean time to diagnose of 2.81 months and treatment length of 8.80 months in Portugal. The proportion defaulting treatment was calculated as 0.04 and the proportion of pulmonary cases as 0.75. Using these values, we estimated a TB burden of 1.6 million infected persons, corresponding to more than 15% of the Portuguese population. We further described the sensitivity of these estimates to heterogeneity.

Conclusions

We showed that the model reproduces well the observed dynamics of the Portuguese data, thus demonstrating its adequacy for devising control strategies for TB and predicting the effects of interventions.

【 授权许可】

   
2014 Lopes et al.; licensee BioMed Central Ltd.

【 图 表 】

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