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Background The Global Influenza Hospital Surveillance Network (GIHSN) aims to determine the burden of severe influenza disease and Influenza Vaccine Effectiveness (IVE). This is a prospective, active surveillance and hospital-based epidemiological study to collect epidemiological data in the GIHSN. In the 2016–2017 influenza season, 15 sites in 14 countries participated in the GIHSN, although the analyses could not be performed in 2 sites. A common core protocol was used in order to make results comparable. Here we present the results of the GIHSN 2016–2017 influenza season. Methods A RT-PCR test was performed to all patients that accomplished the requirements detailed on a common core protocol. Patients admitted were included in the study after signing the informed consent, if they were residents, not institutionalised, not discharged in the previous 30 days from other hospitalisation with symptoms onset within the 7 days prior to admission. Patients 5 years old or more must also complied the Influenza-Like Illness definition. A test negative-design was implemented to perform IVE analysis. IVE was estimated using a logistic regression model, with the formula IVE = (1-aOR) × 100, where aOR is the adjusted Odds Ratio comparing cases and controls. Results Among 21,967 screened patients, 10,140 (46.16%) were included, as they accomplished the inclusion criteria, and tested, and therefore 11,827 (53.84%) patients were excluded. Around 60% of all patients included with laboratory results were recruited at 3 sites. The predominant strain was A(H3N2), detected in 63.6% of the cases (1840 patients), followed by B/Victoria, in 21.3% of the cases (618 patients). There were 2895 influenza positive patients (28.6% of the included patients). A(H1N1)pdm09 strain was mainly found in Mexico. IVE could only be performed in 6 sites separately. Overall IVE was 27.24 (95% CI 15.62–37.27. Vaccination seemed to confer better protection against influenza B and in people 2–4 years, or 85 years old or older. The aOR for hospitalized and testing positive for influenza was 3.02 (95% CI 1.59–5.76) comparing pregnant with non-pregnant women. Conclusions Vaccination prevented around 1 in 4 hospitalisations with influenza. Sparse numbers didn’t allow estimating IVE in all sites separately. Pregnancy was found a risk factor for influenza, having 3 times more risk of being admitted with influenza for pregnant women. Electronic supplementary material The online version of this article (10.1186/s12889-019-6713-5) contains supplementary material, which is available to authorized users.

BackgroundThe Global Influenza Hospital Surveillance Network (GIHSN) aims to determine the burden of severe influenza disease and Influenza Vaccine Effectiveness (IVE). This is a prospective, active surveillance and hospital-based epidemiological study to collect epidemiological data in the GIHSN. In the 2016-2017 influenza season, 15 sites in 14 countries participated in the GIHSN, although the analyses could not be performed in 2 sites. A common core protocol was used in order to make results comparable. Here we present the results of the GIHSN 2016-2017 influenza season.MethodsA RT-PCR test was performed to all patients that accomplished the requirements detailed on a common core protocol. Patients admitted were included in the study after signing the informed consent, if they were residents, not institutionalised, not discharged in the previous 30days from other hospitalisation with symptoms onset within the 7days prior to admission. Patients 5years old or more must also complied the Influenza-Like Illness definition. A test negative-design was implemented to perform IVE analysis. IVE was estimated using a logistic regression model, with the formula IVE=(1-aOR)x100, where aOR is the adjusted Odds Ratio comparing cases and controls.ResultsAmong 21,967 screened patients, 10,140 (46.16%) were included, as they accomplished the inclusion criteria, and tested, and therefore 11,827 (53.84%) patients were excluded. Around 60% of all patients included with laboratory results were recruited at 3 sites. The predominant strain was A(H3N2), detected in 63.6% of the cases (1840 patients), followed by B/Victoria, in 21.3% of the cases (618 patients). There were 2895 influenza positive patients (28.6% of the included patients). A(H1N1)pdm09 strain was mainly found in Mexico. IVE could only be performed in 6 sites separately. Overall IVE was 27.24 (95% CI 15.62-37.27. Vaccination seemed to confer better protection against influenza B and in people 2-4years, or 85years old or older. The aOR for hospitalized and testing positive for influenza was 3.02 (95% CI 1.59-5.76) comparing pregnant with non-pregnant women.ConclusionsVaccination prevented around 1 in 4 hospitalisations with influenza. Sparse numbers didn't allow estimating IVE in all sites separately. Pregnancy was found a risk factor for influenza, having 3 times more risk of being admitted with influenza for pregnant women.

In this paper, are presented the preliminary results of the A.I.D.A. (Auto Immunity: Diagnosis Assisted by computer) project which is developed in the frame of the cross-border cooperation Italy-Tunisia. According to the main objectives of this project, a database of interpreted Indirect ImmunoFluorescence (IIF) images on HEp 2 cells is being collected thanks to the contribution of Italian and Tunisian experts involved in routine diagnosis of autoimmune diseases. Through exchanging images and double reporting; a Gold Standard database, containing around 1000 double reported IIF images with different patterns including negative tests, has been settled. This Gold Standard database has been used for optimization of a computing solution (CADComputer Aided Detection) and for assessment of its added value in order to be used along with an immunologist as a second reader in detection of auto antibodies for autoimmune disease diagnosis. From the preliminary results obtained, the CAD appeared more powerful than junior immunologists used as second readers and may significantly improve their efficacy.

International audience; Auto-reactive cytotoxic T lymphocytes play a key role in the progressive loss or destruction of melanocytes in vitiligo but the mechanism underlying the loss of self-tolerance is unknown. A deregulation of regulatory T-cell biology has recently been suggested. The analysis of the suppressive effects of peripheral T regulatory cells in vitiligo patients revealed a functional defect in seven of 15 cases. This defect was strongly correlated with disease activity. The evaluation of the percentage of peripheral regulatory T lymphocytes did not reveal any intrinsic quantitative defect. Yet, a decrease in the percentage of such cells was noted in patients with progressive forms, suggesting a recruitment of regulatory T cells from the peripheral blood to the site of injury. This was further corroborated by the significant increase of Forkhead box P3 expression in the vitiliginous skin of patients. Our data support the involvement of a functional defect of peripheral regulatory T cells in the pathogenesis of vitiligo and open new possibilities to advance therapeutic approaches.

International audience; Purpose: the aim of this study was to determine the prevalence of cobalamin (vitamin B12) deficiency in different populations of patients with clinical manifestations associated or secondary to cobalamin or folates deficiency and to analyse the demographic, clinical, paraclinical investigations in cobalamin deficient patients in Tunisia. Methods: it was a prospective (19992001) multicenter study of 604 patients divided into four groups. The first group is composed of 478 consecutive patients with anaemia and/or macrocytosis with megaloblastic haemopoiesis on bone marrow examination without myelodyslasic or malignancy signs. The second group is made up of 34 patients with unexplained neurological symptoms without the presence of anaemia. The third group was composed of 82 invidious with isolated psychiatric disorders and the 10 patients with Hashimoto thyroiditis constituted the last,group. Results: serum cobalamin level was low in 98%, 23%, 14% of cases, respectively, in the first three groups. Only one case of patients with Hashimoto thyroiditis has serum cobalamin deficiency. Pernicious anaemia (Biermer's disease) was established by dual isotope schilling examination in 103 patients among a sample of 120 serum cobalamin deficient patients (86%). The median age at presentation was 45.5 years. Severe chronic atrophic gastritis was diagnosed in 97.5% of patients with Biermer's disease. Serum antibodies against intrinsic factor and gastric parietal cells were detected in (42.5%) and (60.6%) patients, respectively; (25.5%) patients had the both types of antibodies. 23.4% patients were positive for antithyroid antibodies. Anti-nuclear antibodies were detected in 3% patients. Conclusion: an interesting finding of our study was the high frequency of cobalamin deficiency in Tunisia, particularly in relative young patients. Our patients had classic features of florid cobalamin deficiency (severe haematological manifestations and neuro-psychiatric disorders). The main underlying causes of such deficiencies were Biermer's disease. Subtle clinical manifestations should be recognized and investigated even in young patients at risk.; Objectif : déterminer la prévalence des déficits en cobalamines (vitamine B12) chez différentes populations de patients présentant des manifestations cliniques pouvant être associées ou secondaires à un déficit en vitamine B12 ou en folates et analyser les données démographiques, cliniques et paracliniques chez les patients déficitaires en vitamine B12 en Tunisie. Méthodes : il s’agissait d’une étude prospective (1999-2001), multicentrique, incluant 604 patients répartis en quatre groupes : le premier groupe comportait 478 patients consécutifs présentant une hématopoïèse mégaloblastique sans signe de myélodysplasie avec ou sans anémie. Le deuxième groupe était composé de 34 patients présentant un tableau neurologique inexpliqué sans anémie mégaloblastique associée. Le troisième groupe était constitué de 82 individus présentant des manifestations psychiques isolées. Le quatrième groupe comportait dix patients ayant une thyroïdite d’Hashimoto. Résultats : le taux des cobalamines sériques était bas dans 98 %, 23 %, 14 % des cas, respectivement, des trois premiers groupes, alors qu’un seul patient du quatrième groupe était déficitaire en vitamine B12. Le test de Schilling réalisé chez un échantillon de 120 patients déficitaires en cobalamines a montré que 103 patients (86 %) étaient atteints par la maladie de Biermer. Ils avaient une médiane d’âge de 45,5 ans ; 97,5 % d’entre eux avaient une gastrite fundique atrophique sévère. L’Helicobacter pylori a été détecté chez seulement 5 parmi les 43 patients où il a été histologiquement recherché. Le bilan auto-immun chez ces patients montre : anticorps anti-cellules pariétales : 60,6 % ; anticorps anti-facteur intrinsèque : 42,5 % ; concordance entre les 2 anticorps : 48% ; anticorps anti-thyroïdiens : 23,4 % (2 % chez les témoins normaux) ; anticorps anti-nucléaire : 3 %. Conclusion : notre travail souligne la fréquence élevée des déficits en vitamine B12 en Tunisie particulièrement chez les sujets relativement jeunes. Nos patients présentaient un tableau clinique des formes florides des déficits en cobalamines (manifestations hématologiques sévères et troubles neuropsychiatriques). La cause principale sous-jacente de ces déficits était la maladie de Biermer. Les formes cliniques frustes méritent d’être recherchées et explorées même chez les sujets jeunes à risque.

International audience; Natural autoantibodies (NaAb) and IgG antibodies to tetanus toxoid (TT) were analysed in the sera of 38 children with active visceral leishmaniasis (VL) previously vaccinated with TT and in 30 healthy controls matched for sex and age. Patients exhibited high levels of NaAb to a panel of self antigens (tubulin, myosin, myoglobin, actin) contrasting to a low level of IgG to TT. Analysis of the circulating B cells in 26 untreated patients showed a low percentage of CD5+ per total B cells (3-66%, mean 36.6%) compared with 14 normal controls (17.8-66.6%, mean 52.7%) (P < 0.001). Evaluation of these parameters after antimonial therapy showed a significant decrease of the level of the NaAb (P < 0.0005), and a spontaneous increase of the level of the IgG to TT without any vaccine boosting (P < 0.01). In contrast, there was a significant increase in CD5+ B cells (P < 0.0005). This result suggests that CD5+ B cells may be sequestrated in parasitized lymphoid organs and may be released after remission. These findings show that the polyclonal B cell activation that occurs during active VL involves mainly B cells bearing NaAb and are in favour of a functional dichotomy of B cells.

International audience; Recently, tomato yellow leaf curl disease has become important for the tomato grown both in greenhouse and field conditions in Tunisia. Here, we describe a rapid, specific, reliable, and sensitive real-time PCR, based on TaqMan (R) chemistry, for Tomato yellow leaf curl Sardinia virus (TYLCSV). This method proved suitable for the detection and quantification of this virus in tomato, pepper and bean plants. It detected the virus even in the samples that were negative by conventional assays.