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Objectives: The genetic diversity of Mycobacterium tuberculosis complex (MTBC) influences the immune response of the host, which may affect the immunodiagnostic tests and biomarker assessment studies used for tuberculosis (TB). This study aimed to determine whether the mycobacterial-antigen-stimulated cytokine responses vary with the genotype of the MTBC infecting the patient. Methods: Eighty-one patients with confirmed active pulmonary TB were recruited, and MTBC clinical strains were isolated from their sputum for bacterial lineage single-nucleotide polymorphism typing. Whole blood was drawn from the patients to measure the purified protein derivative (PPD)-stimulated cytokine responses (GM-CSF, IFN-γ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, TNF-α, IFN-α, IL-12, eotaxin, IL-13, IL-15, IL-17, MIP1-α, MIP1-β, MCP1, IL1RA, IP10, IL2R, MIG) with the Luminex multiplex immunoassay. Results: Of the 24 cytokines studied, three were produced differentially in whole blood dependent on the infecting lineage of MTBC. Decreased production of IL-17 was observed in patients infected with modern lineages compared with patients infected with ancestral lineages (P < 0.01), and production of IFN-γ and IL-2 was significantly decreased in patients infected with lineage 4 strains compared with patients infected with lineage 3 strains (P < 0.05). Conclusion: MTBC strains belonging to lineage 4 induced a decreased whole-blood PPD-stimulated pro-inflammatory cytokine response.

Objectives: Schistosomiasis is an important disease in Madagascar, and several studies on the disease have focused on the occurrence of the parasite in humans. However, the range of the pathogen in the environment and its impact on human infection is difficult to predict. An environmental DNA (eDNA) detection system for Schistosoma mansoni was developed to improve schistosomiasis eco-epidemiology studies. Methods: Primers and probes were designed and tested in experimental biotopes. The field study was conducted in Maevatanana District of Madagascar. Seven water sources with human use were sampled, with a total of 21 water samples collected. Snails were collected, and patients were examined by ultrasound to determine the occurrence of schistosomiasis in the study area. Results: One water source with active transmission was identified through the detection of S. mansoni eDNA in the water and the intermediate host Biomphalaria pfeifferi collected from the same water source. People with clinical schistosomiasis were found in the area, reinforcing the findings. Conclusions: The application of eDNA in eco-epidemiology enables the determination of hot spots and safe spots in endemic areas, constituting an alternative ecological tool for follow-up and monitoring of control programs for schistosomiasis, and contributing information on water safety for improving the standard of living of the people in endemic areas. Keywords: Eco-epidemiology, EcoHealth, One Health, Environment, Schistosomiasis, Africa, Madagascar, eDNA

Tuberculosis (TB) is an infectious disease of global public health importance caused by Mycobacterium tuberculosis complex. The disease has worsened with the emergence of multidrug-resistant (MDR)-TB strains. The timely diagnosis and treatment of TB remains a key public health priority, and laboratories have a critical role in the rapid and accurate detection of TB and drug resistance. Molecular assays based on nucleic acid amplification techniques have been developed for the rapid, sensitive, and specific diagnosis of TB, with the ability to determine the drug sensitivity status. These molecular techniques are now available or are being implemented in developing countries. However, traditional microscopy and culture methods cannot yet be replaced; the molecular assays can be applied in parallel with these tests for the diagnosis of TB or for drug susceptibility testing. Performing such molecular tests is often restricted by constraints with regard to sputum sample storage and safe transportation from remote health centres to central laboratories. Since smear slides are performed routinely for the diagnosis of TB in most TB diagnostic laboratories, they are readily available and could be the ideal tool to transport sputum for further molecular tests. The aim of this review was to provide a comprehensive survey on the use of smear slides for both TB diagnosis and the molecular test approach. Based on the literature, stained smear microscopy slides can be a safe system for the transportation of sputum specimens from remote health centres to reference TB laboratories for further molecular TB or MDR-TB detection, and could help in the rapid diagnosis and therefore timely management of TB patients.