Description
Tuberculosis (TB) is known to be associated with socioeconomic inequalities. Knowing that Portugal is nowadays facing a particularly serious situation concerning financial sustainability, and given the current lack of knowledge on the local molecular epidemiology of TB, we believe it is both timely and pertinent to launch this proposal, aiming at decrease TB-associated morbidity and mortality. We will address two vulnerable groups in an urban center in the north of Portugal – the homeless and the HIV-infected patients – with the goals of establishing an active screening strategy for early TB diagnosis and treatment, as well as identifying specific risk factors for TB development. Moreover, we will proceed with the genotype of all Mycobacterium tuberculosis isolation in the area and complement that epidemiological information with a geographical information system. We expect to gain insight into the Mtb association with clinical/demographic features, and geographic perspective of the existing outbreaks’ dynamics.
Summary of project results
In Portugal, incidence rates of tuberculosis has been steadily declining in the last decades, coming under 20 cases per 100 thousand in 2015. Reaching the low incidence status brings some new challenges, namely the need to identify and prioritize intervention in vulnerable sub-populations who are at increased risk of contracting the disease. An increasing proportion of cases of TB occur in big urban centres, where transmission chains are especially hard to break due to unfavourable socioeconomic factors. In this project, 2 vulnerable groups from an urban centre in Northern Portugal were targeted – homeless and HIV-infected people – with the aim of establishing an effective strategy of diagnosis and early treatment of TB, as well as identifying specific risk factors for the development of the disease. 403 screenings were conducted and 2 TB cases identified as well as 139 HIV patients admitted in Oporto hospitals for TB infection, of which 44,6% were living in a vulnerable social situation. After the implementation of this project it became apparent that main risk factors in Porto are related to homelessness and HIV-infection, somewhat differently than in the main urban area of the country (Lisbon). Also as a result of this project, screening and treatment of the individuals belonging to these sub-populations started being organized more efficiently. New molecular epidemiology tools, through genotyping of TB strains, along with geo-referencing data from the identified TB cases, proved to be a very useful tool to complement routine public health investigation – as it showed that some cases were linked and some others were not and had never been recognized as such by public health teams. The implementation of a routine TB strain genotyping allowed a better understanding of the transmission chains in this area, supporting tailored public health interventions that will have impact further reducing the burden of disease in the country. Also as a result of this project, outbreaks that had not been previously recognized triggered enhanced public health surveillance and the creation of multidisciplinary investigation teams, that in the future will support a swifter response and allow the prevention of new cases of TB arising in Porto urban area.
Summary of bilateral results