Humoral and Cellular Immunogenicity of Six Different Vaccines against SARS-CoV-2 in Adults: A Comparative Study in Tunisia (North Africa).

BACKGROUND: The mass vaccination campaign against SARS-CoV-2 was started in Tunisia on 13 March 2021 by using progressively seven different vaccines approved for emergency use. Herein, we aimed to evaluate the humoral and cellular immunity in subjects aged 40 years and over who received one of the following two-dose regimen vaccines against SARS-CoV-2, namely mRNA-1273 or Spikevax (Moderna), BNT162B2 or Comirnaty (Pfizer-BioNTech), Gam-COVID-Vac or Sputnik V (Gamaleya Research Institute), ChAdOx1-S or Vaxzevria (AstraZeneca), BIBP (Sinopharm), and Coronavac (Sinovac). MATERIAL AND METHODS: For each type of vaccine, a sample of subjects aged 40 and over was randomly selected from the national platform for monitoring COVID-19 vaccination and contacted to participate to this study. All consenting participants were sampled for peripheral blood at 3-7 weeks after the second vaccine dose to perform anti-S and anti-N serology by the Elecsys® (Lenexa, KS, USA) anti-SARS-CoV-2 assays (Roche® Basel, Switzerland). The CD4 and CD8 T cell responses were evaluated by the QuantiFERON® SARS-CoV-2 (Qiagen® Basel, Switzerland) for a randomly selected sub-group. RESULTS: A total of 501 people consented to the study and, of them, 133 were included for the cellular response investigations. Both humoral and cellular immune responses against SARS-CoV-2 antigens differed significantly between all tested groups. RNA vaccines induced the highest levels of humoral and cellular anti-S responses followed by adenovirus vaccines and then by inactivated vaccines. Vaccines from the same platform induced similar levels of specific anti-S immune responses except in the case of the Sputnik V and the AstraZeneca vaccine, which exhibited contrasting effects on humoral and cellular responses. When analyses were performed in subjects with negative anti-N antibodies, results were similar to those obtained within the total cohort, except for the Moderna vaccine, which gave a better cellular immune response than the Pfizer vaccine and RNA vaccines, which induced similar cellular immune responses to those of adenovirus vaccines. CONCLUSION: Collectively, our data confirmed the superiority of the RNA-based COVID-19 vaccines, in particular that of Moderna, for both humoral and cellular immunogenicity. Our results comparing between different vaccine platforms in a similar population are of great importance since they may help decision makers to adopt the best strategy for further national vaccination programs.

A double burden of overall or central adiposity and anemia or iron deficiency is prevalent but with little socioeconomic patterning among Moroccan and Tunisian urban women.

In North Africa, overnutrition has dramatically increased with the nutrition transition while micronutrient deficiencies persist, resulting in clustering of opposite types of malnutrition that can present a unique difficulty for public health interventions. We assessed the magnitude of the double burden of malnutrition among urban Moroccan and Tunisian women, as defined by the coexistence of overall or central adiposity and anemia or iron deficiency (ID), and explored the sociodemographic patterning of individual double burden. In cross-sectional surveys representative of the region around the capital city, we randomly selected 811 and 1689 nonpregnant women aged 20-49 y in Morocco and Tunisia, respectively. Four double burdens were analyzed: overweight (body mass index ≥25 kg/m(2)) or increased risk abdominal obesity (waist circumference ≥80 cm) and anemia (blood hemoglobin <120 g/L) or ID (C-reactive protein-corrected serum ferritin <15 µg/L). Adjusted associations with 9 sociodemographic factors were estimated by logistic regression. The prevalence of overweight and ID was 67.0% and 45.2% in Morocco, respectively, and 69.5% and 27.0% in Tunisia, respectively, illustrating the population-level double burden. The coexistence of overall or central adiposity with ID was found in 29.8% and 30.1% of women in Morocco, respectively, and in 18.2% and 18.3% of women in Tunisia, respectively, quite evenly distributed across age, economic, or education groups. Generally, the rare, associated sociodemographic factors varied across the 4 subject-level double burdens and the 2 countries and differed from those usually associated with adiposity, anemia, or ID. Any double burden combining adiposity and anemia or ID should therefore be taken into consideration in all women. This trial was registered at clinicaltrials.gov as NCT01844349.

Dietary fiber in the diets of urban Tunisian women: association of fiber intake with BMI, waist circumference and blood chemistry: preliminary study.

BACKGROUND: The change of the way of life and the food practices in Tunisia due inter alia to the improvement of the socioeconomic conditions induced low fuel consumption of food with significant nutritional interest such as those rich in food fibres which have positive effects on the reduction and the prevention of some complications of the metabolic diseases such as the obesity whose prevalence among Tunisian women is increasingly high. OBJECTIVE: We assessed the association between the mean daily fiber intake and anthropometric parameters, the serum lipid profile and the serum glucose concentration among urban Tunisian women. METHODS: We conducted a 7-day food weighing method among 260 women of which 60 are obese (BMI > 30 kg/m(2)). The weighing method was done by trained and experienced workers in the National Institute of Nutrition of Tunisia. All the results were treated with the (Bilnut) software (1991 version) to which a list of 235 special Tunisian foods was added. We calculated their mean daily fiber intake and we prospectively evaluated the correlations between it and the BMI, the waist circumference, total plasma cholesterol, HDL-cholesterol, triglyceridemia and glycaemia. RESULTS: Obese women are found to consume less fiber than non-obese women (21.73 ± 3.25 g/day vs 26.25 ± 2.7 g/day; P<0.0001). Very high and significant correlations were observed between dietary fiber intake and the parameters investigated: BMI (r=-0.709, P<0.0001), waist circumference (r=-0.790; P<0.0001), total plasma cholesterol (r=-0.488; P<0.0001), triglyceridemia (r=-0.741; P<0.0001) and glycaemia (r=-0.557, P<0.0001). However, we find a positive but a non significant correlation with the HDL-cholesterol and the mean daily fiber intake (r=0.309; P=0.02). CONCLUSIONS: This study provides additional support to the inverse association between fiber consumption and weight gain, the serum lipid profiles, the glycaemia and the waist circumference. Our findings emphasizes the relevance of increased the intakes of fiber from varied sources that may help avoid weight gain among obese adults.

[Renal failure in Tunisian patients with type 2 diabetes: frequency and related factors]. / L'insuffisance rénale chez des diabétiques de type 2 Tunisiens hospitalises: frequence et fateurs associés.

BACKGROUND: Frequent screening of renal failure and good glycaemic control in diabetic patients can avoid this severe complication. AIM: To evaluate the frequency of renal failure and the associated risk factors among type 2 diabetic Tunisian in-patients. Glomerular filtration rate was estimated using the Cockcroft-Gault formula. Renal failure was diagnosed on figure of glomerular filtration rate inferior than 60 ml/min. RESULTS: Six hundred eighty-nine patients were included. The sex ratio was 0.65. The mean age was 60 ± 11 years. The frequency of renal failure was 19.8% (137 patients) with dominance of a moderate form defined by a glomerular filtration rate between 30 and 59 ml/min (82.5% of patients). Patients with renal failure were older and less obese than diabetic patients without this complication (p<0.00001 and 0.02 respectively). The duration of both diabetes and hypertension was higher in presence of renal failure (p=0.0001 and p<0.001 respectively). Patients with renal failure had more often hypertension and dyslipidemia than patients with normal renal function (p<0.001 and p=0.01 respectively). A personal history of severe retinopathy treated by laser, of coronary disease or of stroke was significantly associated to renal failure (p=0.002, p<0.0001 and p=0.001 respectively). CONCLUSION: The frequency of renal failure observed in Tunisian patients diagnosed with type 2 diabetes is high. Hypertension and dyslipidemia should be carefully treated to prevent or delay the evolution to the renal failure.

[Distribution and prevalence of dyslipidemia in Tunisia: results of the Tunisian National Nutrition Survey]. / Distribution et prevalence des dyslipidemies en Tunisie: resultats de l'Enquete Nationale de Nutrition.

UNLABELLED: The aims of the study were to study the distribution of cholesterol and triglycerides and to assess the prevalence of dyslipemia in Tunisian adult population. METHODS: The Tunisian National Nutrition Survey (TNNS) was a cross sectional study performed on a total of 7860 adult subjects and was conducted on 1996-1997. The TNNS included 3087 adults over 20 years old. RESULTS: The mean values of cholesterol (CT) were more elevated in urban than rural area (p<0.001), and in females than in males (p<0.007). The overall prevalence of hypercholesterolemia (CT > 6.2 mmol/l) was 8.4% and that of hypertriglyceridemia (TG > 1.70 mmol/l) was 21%. The prevalence of borderline high cholesterol (> or =5.2-< 6.2 mmol/l) was 17%; These prevalences were more elevated in urban than rural areas (p <0.001) and increased with age in both genders (p < 0.001). The multiple adjusted odd ratio of the prevalence of hypercholesterolemia showed a positive correlation with female sex (OR 1.40 p <0.01), high waist circumference (OR 2.51 in men and 3.04 in women p < 0001) and urban residency (OR 1.35 p = 0.03). CONCLUSION: Our study showed the metabolic consequences of westernization style life in our country and should be the starter to preventive adequate policy.

Aetiological factors and perception of anaemia in Tunisian women of reproductive age.

OBJECTIVES: To identify aetiological factors in anaemia and to explore knowledge, perceptions and attitudes towards anaemia. DESIGN: Two cross-sectional surveys and sixteen focus group discussions. SETTING: The two regions with the highest prevalence of anaemia in Tunisia, Greater Tunis (GT) and the South West (SW). SUBJECTS: Two representative samples of 687 (GT) and 729 (SW) women of reproductive age; 108 women were included in focus group discussions. RESULTS: Among anaemic women, 63.4% in the GT region and 80.2% in the SW displayed iron deficiency (ID). Genetic haemoglobinopathies accounted for 10.0% and 3.6% of the cases of anaemia in the two regions, respectively. After adjustment for confounders, the major factors for iron-deficiency anaemia were low dietary Fe intake (OR = 5.0, 95% CI 3.0, 8.4), drinking tea after eating (OR = 3.4, 95% CI 2.0, 5.7) and pica (OR = 2.1, 95% CI 1.1, 3.9). Most of the women related anaemia to the following causes: malnutrition, lack of hygiene, and their heavy workload and responsibilities in the household. Many women connected anaemia with hypotension. Few established a relationship between ID and anaemia. They had confidence in their doctor for treatment, but many complained they were not given sufficient information. Low dietary Fe intake, inappropriate food practices and inadequate perceptions contribute to the aetiology of anaemia in women. CONCLUSIONS: These results point out to the need for a strategy combining food fortification, Fe supplementation for pregnant women, nutritional education for the general public and at-risk specific target groups, and training of health professionals.

Tunisian children reference for body mass index and prevalence of obesity.

BACKGROUND: The prevalence of obesity in children is known to be increasing rapidly worldwide but few population-based surveys have been undertaken in North Africa and in the Middle East. AIMS: Report the means of body mass index with values corresponding to the different percentiles in boys and girls by age from a large nationally representative sample of the Tunisian children population. The second aim was to estimate the prevalence of obesity and over weight in children and adolescent using the 85th and 95th body mass index percentile respectively derived from the U.S.A. first National Health and Nutrition Survey and also the International cut off points for body mass index for overweight and obesity proposed by the International Obesity Task Force and Rolland Cachera. SUBJECTS AND METHODS: We have used data from the Tunisian National Nutrition Survey, a cross sectional health study providing a large nationally representative sample of the Tunisian population including 3885 children and adolescent. RESULTS: The mean of BMI was of 16,63 +/- 2,58 Kg/m2 among boys and 17.36 +/- 3.52 Kg/m in girls. The BMI increased with age and more precociously in girls (10 years) that in boys (13-14 years). The mean+2SD of the BMI approached the 95th percentile. It is noticed that our 85th percentile and 95th percentile as well in the girls and in boys were lower than the same percentiles of the children of other countries (NHANES I, IOTF) and that our 97th percentile is higher than that of the French according to tables of Roland Cachera. By conside ring the NHANES I and the IOTF, the prevalence of obesity were rather weak (<5%) but high according to the tables of Roland Cachera (3 to 11%). CONCLUSION: The prevalence of obesity was low in 1996 according to references' of the NHANES I and IOTF but high according to tables' of Roland Cachera. Prevention of obesity by a healthy way of life remains the most effective means in the long and undoubtedly less expensive realizing programs of regular monitoring.