Evaluation of the influenza-like illness sentinel surveillance system: A national perspective in Tanzania from January to December 2019.

BACKGROUND: The World Health Organization (WHO) recommends periodic evaluations of influenza surveillance systems to identify areas for improvement and provide evidence of data reliability for policymaking. However, data on the performance of established influenza surveillance systems are limited in Africa, including Tanzania. We aimed to assess the usefulness of the Influenza surveillance system in Tanzania and to ascertain if the system meets its objectives, including; estimating the burden of disease caused by the Influenza virus in Tanzania and identifying any circulating viral strains with pandemic potential. METHODOLOGY: From March to April 2021, we collected retrospective data through a review of the Tanzania National Influenza Surveillance System electronic forms for 2019. Furthermore, we interviewed the surveillance personnel about the system's description and operating procedures. Case definition (ILI-Influenza Like Illness and SARI-Severe Acute Respiratory Illness), results, and demographic characteristics of each patient were obtained from the Laboratory Information System (Disa*Lab) at Tanzania National Influenza Center. The United States Centers for disease control and prevention updated guidelines for evaluating public health surveillance systems were used to evaluate the system's attributes. Additionally, the system's performance indicators (including turnaround time) were obtained by evaluating Surveillance system attributes, each being scored on a scale of 1 to 5 (very poor to excellent performance). RESULTS: A total of 1731 nasopharyngeal and oropharyngeal samples were collected from each suspected influenza case in 2019 from fourteen (14/14) sentinel sites of the influenza surveillance system in Tanzania. Laboratory-confirmed cases were 21.5% (373/1731) with a predictive value positive of 21.7%. The majority of patients (76.1%) tested positive for Influenza A. Thirty-seven percent of patients' results met the required turnaround time, and 40% of case-based forms were incompletely filled. Although the accuracy of the data was good (100%), the consistency of the data was below (77%) the established target of ≥ 95%. CONCLUSION: The overall system performance was satisfactory in conforming with its objectives and generating accurate data, with an average performance of 100%. The system's complexity contributed to the reduced consistency of data from sentinel sites to the National Public Health Laboratory of Tanzania. Improvement in the use of the available data could be made to inform and promote preventive measures, especially among the most vulnerable population. Increasing sentinel sites would increase population coverage and the level of system representativeness.

Influence of diet quality on nutritional status of school-aged children and adolescents in Zanzibar, Tanzania.

BACKGROUND: Malnutrition among young children and adolescents poses a serious health challenge in developing countries which results in many health problems during adulthood. Poor diet quality is known as the root cause of malnutrition which is caused by unhealthy food choices and bad eating habits among young children and adolescents. However, limited evidence is available on diet quality and its association with nutrition status among young children and adolescents in Zanzibar. This study examined the diet quality and its relationship with the nutritional status of school-aged children and adolescents in Zanzibar. METHODS: Data for this study was obtained from the cross-sectional survey of School Health and Nutrition (SHN) conducted in Zanzibar. The survey recruited children aged 5-19 years from 93 schools in Zanzibar. A seven-day food frequency questionnaire (FFQ) was used to assess dietary intake. Prime Dietary Quality Score (PDQS) consisted of 21 food groups was then constructed to assess the diet quality of school-aged children and adolescents. Body mass index (BMI-for-age Z-score) was used as the indicator of nutrition status. Both linear and logistic regression analysis techniques were used to determine the associations between BMI and PDQS. RESULTS: A total data of 2,556 children were enrolled in the survey. The prevalence of thinness was 8.1%, normal 82.1%, overweight 7.2% and obesity 2.6%. The mean (SD) PDQS score was 18.8 (3.2) which ranged from 8 to 33. Consumptions of green leafy vegetables (49.3%), yellow or red fruits (37.8%), legumes (38.3%), fish (36.3%), and vegetable oil (31.5%) were up to three times per week, whereas consumptions of white vegetables (77.3%), cooked vegetables (32.6%), citrus fruits (66.8%), other types of fruits (66.2%), nuts (46.4%), poultry (49.6%), whole grains (61%) and eggs (67.8%) were less than once per week. In terms of unhealthy foods, eating fried foods was reported by 26.3% up to three times per week, and 31.5% reported consuming sweets and ice cream up to three times in the past week. High PDQS was significantly associated with a reduction in BMI of children (p< 0.005). For each unit increase in the consumption of unhealthy foods such as fried foods, cooked vegetables and refined grains there is a significant increase in BMI. The odds of being obese decrease significantly as diet quality increases from the first to third quintile of PDQS (AOR = 0.2, 0.04-0.89 95% CI, p = 0.035). CONCLUSION: Consumption of high quality diet was found to be associated with a reduction in excessive weight among school-aged children and adolescents in Zanzibar. There is a need for interventions targeting to reduce unhealthy food consumption in school environment. Further research should be conducted to assess diet quality using PDQS among young children and adolescents.

Scaling-up the delivery of dog vaccination campaigns against rabies in Tanzania.

An increasing number of countries are committing to meet the global target to eliminate human deaths from dog-mediated rabies by 2030. Mass dog vaccination is central to this strategy. To interrupt rabies transmission from dogs to humans, the World Health Organization recommends that vaccination campaigns should be carried out every year in all dog-owning communities vaccinating 70% of their susceptible dogs. Monitoring and evaluation of dog vaccination campaigns are needed to measure progress towards elimination. In this study, we measured the delivery performance of large-scale vaccination campaigns implemented in 25 districts in south-east Tanzania from 2010 until 2017. We used regression modelling to infer the factors associated with, and potentially influencing the successful delivery of vaccination campaigns. During 2010-2017, five rounds of vaccination campaigns were carried out, vaccinating in total 349,513 dogs in 2,066 administrative vaccination units (rural villages or urban wards). Progressively more dogs were vaccinated over the successive campaigns. The campaigns did not reach all vaccination units each year, with only 16-28% of districts achieving 100% campaign completeness (where all units were vaccinated). During 2013-2017 when vaccination coverage was monitored, approximately 20% of vaccination units achieved the recommended 70% coverage, with average coverage around 50%. Campaigns were also not completed at annual intervals, with the longest interval between campaigns being 27 months. Our analysis revealed that districts with higher budgets generally achieved higher completeness, with a twofold difference in district budget increasing the odds of a vaccination unit being reached by a campaign by slightly more than twofold (OR: 2.29; 95% CI: 1.69-3.09). However, higher budgets did not necessarily result in higher coverage within vaccination units that were reached. We recommend national programs regularly monitor and evaluate the performance of their vaccination campaigns, so as to identify factors hindering their effective delivery and to guide remedial action.