For the effective control of tuberculosis (TB) strategies are needed to prevent transmission. Absence of obvious symptoms for long periods after initial infection delays diagnosis and facilitates transmission. Public Health authorities in Porto have made a remarkable effort to identify individuals at high risk of having contact with TB cases and of developing the disease. The initiatives include tracing contacts identified during the epidemiological investigation and specific strategies for the maismost vulnerable indivíduosindividuals. However, recent results from the team, based on genetic analysis of Mycobacterium tuberculosis (Mtb) strains from 2014-15, revealed that current strategies are insufficient. Porto has a great diversity of Mtb strains and a complex transmission scenario. Greater follow-up is therefore essential for a more detailed understanding of transmission chains. In this sense, 4 years of longitudinal analysis of Mtbno Porto strains will be added to the previous analysis.
Mtb isolates from all cases residing in the Greater Porto laboratory confirmed in the laboratory will be genotyped using a certified in-house platform. This genetic characterization will be complemented by the sequencing of complete genomes of strains representative of the genetic diversity of Mtb strains.
With the aim of improving TB screening strategies, we will seek to develop a simple and fast diagnostic method, based on mass spectrometry with a portable device. To improve the identification of individuals who are at higher risk and who should follow specific screening programs, immunological markers of greater vulnerability will be investigated using mass cytometry in collaboration with the Karolinska Institute (KI) in Sweden.
This project will be developed by a multidisciplinary team that aims to generate data in three fundamental aspects to improve TB control strategies: 1) full understanding of transmission chains; 2) determination of the exact role of the most vulnerable groups in active transmission and 3) improvement of diagnostic methods and susceptibility markers for early diagnosis and screening of TB.
Genetic (ICVS members) and epidemiological (ISPUP) data will be combined using a bioinformatics platform developed by team members (ICVS) to better understand transmission chains and the role of the most vulnerable groups. This will be complemented with advances in the method of diagnosis (CBQF) and immunological markers of increased susceptibility (ICVS and KI). Public health specialists (ISPUP) will integrate the information to suggest improved strategies for the controlof TTB in Porto and potentially to other cities in Portugal and other European countries.