Prevalence and risk factors for latent tuberculosis infection among healthcare workers in Morocco.

Increased prevalence of latent tuberculosis infection (LTBI) has been observed among high-risk populations such as healthcare workers (HCWs). The results may depend on the method of LTBI assessment, interferon-gamma release assay (IGRA) and/or tuberculin skin test (TST). Here, we investigated the prevalence and risk factors for LTBI assessed by both IGRAs and TST in HCWs living in Morocco, a country with intermediate tuberculosis (TB) endemicity and high BCG vaccination coverage. HCWs were recruited in two Moroccan hospitals, Rabat and Meknes. All the participants underwent testing for LTBI by both IGRA (QuantiFERON-TB Gold In-Tube, QFT-GIT) and TST. Different combinations of IGRA and TST results defined the LTBI status. Risk factors associated with LTBI were investigated using a mixed-effect logistic regression model. The prevalence of LTBI among 631 HCWs (age range 18-60 years) varied from 40.7% (95%CI 36.9-44.5%) with QFT-GIT to 52% (95%CI 48.2-56.0%) with TST using a 10 mm cut-off. The highest agreement between QFT-GIT and TST (κ = 0.50; 95%CI 0.43-0.56) was observed with the 10 mm cut-off for a positive TST. For a definition of LTBI status using a double positive result for both QFT-GIT and TST, significant associations were found with the following risk factors: being male (OR = 2.21; 95%CI 1.40-3.49; p = 0.0007), belonging to age groups 35-44 years (OR = 2.43; 95%CI 1.45-4.06; p = 0.0007) and even more 45-60 years (OR = 4.81; 95%CI 2.72-8.52; p = 7.10-8), having a family history of TB (OR = 6.62; 95%CI 2.59-16.94; p = 8.10-5), and working at a pulmonology unit (OR = 3.64; 95%CI 1.44-9.23; p = 0.006). Smoking was associated with LTBI status when defined by a positive QFT-GIT result (OR = 1.89; 95%CI 1.12-3.21; p = 0.02). A high prevalence of LTBI was observed among HCWs in two Moroccan hospitals. Male gender, increased age, family history of TB, and working at a pulmonology unit were consistent risk factors associated with LTBI.

Antibacterial activity, structure and CMC relationships of alkanediyl alpha,omega-bis(dimethylammonium bromide) surfactants.

Some alpha,omega-alkanediyl bis-dimethylammonium bromide compounds (gemini surfactants) referred as "m-s-m" have been synthesized, purified and characterized by usual spectroscopic methods. These compounds have been screened for antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. Their activity was compared. The compounds tested showed excellent in vitro antibacterial activity against Staphylococcus aureus ranging from 1.5 to 20 microg/ml and had variable activity against E. coli with minimum minimum inhibitory concentration (MIC) of 50 microg/ml. These compounds are less active against P. aeruginosa. On the other hand, contrary to the antibacterial activity of these products against S. aureus, a relation between the MIC and the critical micellar concentration (CMC) was found and relationship between chain's Length and antibacterial activity was found.