Modelling of seasonal influenza and estimation of the burden in Tunisia

The burden of influenza was estimated from surveillance data in Tunisia using epidemiological parameters of transmission with WHO classical tools and mathematical modelling. The incidence rates of influenza-associated influenza-like illness [ILI] per 100 000 were 18 735 in 2012/2013 season; 5536 in 2013/14 and 12 602 in 2014/15. The estimated proportions of influenza-associated ILI in the total outpatient load were 3.16%; 0.86% and 1.98% in the 3 seasons respectively. Distribution of influenza viruses among positive patients was: A[H3N2] 15.5%; A[H1N1] pdm2009 39.2%; and B virus 45.3% in 2014/2015 season. From the estimated numbers of symptomatic cases, we estimated that the critical proportions of the population that should be vaccinated were 15%, 4% and 10% respectively. Running the model for the different values of R0, we quantified the number of symptomatic clinical cases, the clinical attack rates, the symptomatic clinical attack rates and the number of deaths. More realistic versions of this model and improved estimates of parameters from surveillance data will strengthen the estimation of the burden of influenza

[Risk factors of leishmanin-skin test positivity in transmission of Leishmania infantum in the center of Tunisia]

This work aims to estimate prevalence and evaluate risk factors of leishmanin-skin test positivity. A cross-sectional leishmanin skin test study was carried out on a sample of 3190 healthy volunteers living in the gouvernorates of Kairouan and Kasserine. Age standardized prevalence of leishmanin-skin test positivity was 45.9% [CI95% = [43.9-47.9]] confirming the hyper endemicity of this region. The rate of leishmanin-skin test positivity ranged from 75.9% [CI95% = [71.9-79.5]] in Zaghdoud [Kairouan] to 6.5% [CI95% = [3.7-11.01] in Abdeladhim [Kasserine]. There is no significant difference between men and women suggesting a similar exposure to infection. In the districts of Zaghdoud, Sidi Amor, El Hajeb and chbika, age specific rates showed a rapid increasing positive prevalence with age reaching a proportion exceeding 80% after the age of 15 years. However, the age specific prevalence from other delegations showed a progressive increasing trend with age, with a low rate for younger children and a plateau of 75% after 45 years. Multivariate analysis of leishmanin-skin test positivity risk factors showed that only district and age are determinants of this infection