[Evaluation of the Viral Hemorrhagic Fever Surveillance System in the Assaba region, Mauritania (2020-2022)]. / Évaluation du système de surveillance des fièvres hémorragiques virales dans la wilaya d'Assaba, Mauritanie (2020-2022).

Introduction: Several arboviral diseases have been known to be endemic (e.g., Crimean-Congo hemorrhagic fever, Rift Valley fever) or are emerging (dengue fever, chikungunya, O'nyong-nyong) in human populations in Mauritania, while others have become rare in recent years (e.g. yellow fever). Moreover, domestic animals, especially cattle, camels, goats, and sheep, are also known to be infected with some of these arboviruses (e.g. Crimean-Congo hemorrhagic fever, Rift Valley fever). For these reasons, viral hemorrhagic fever surveillance in Mauritania is part of the Integrated Disease Surveillance and Response (IDSR). However, limited information is available on the efficacy of the viral hemorrhagic fever surveillance system in the Assaba region of Mauritania. The aim of the present study was to assess the performance of the surveillance system, in particular its general utility, simplicity, flexibility, acceptability, and reactivity. Methods: A descriptive cross-sectional study was conducted from July to August 2022 in the Assaba region with the objective of evaluating the characteristics of the system by interviewing key actors involved in the surveillance of viral hemorrhagic fevers, with a focus on Rift Valley fever and Crimean-Congo hemorrhagic fever, using questionnaires developed following the guidelines of the Centers for Disease Control and Prevention (Atlanta, Georgia, USA). Data from 2020-2022 on viral hemorrhagic fevers from the National Institute of Public Health laboratory were analyzed. Medians, interquartile ranges, and proportions were calculated using Epi Info® 7.2.5.0 and Excel® 2021. Results: The questionnaire was answered by all twenty-six persons involved in the viral hemorrhagic fever surveillance system in Assaba region. The majority of survey respondents found the system to be useful (51%), simple (63%), acceptable (46%), responsive (64%), and flexible (46%). An analysis of the data revealed a positive predictive value of 28% for Rift Valley Fever. The weekly distribution of cases within the wilaya indicates that the moughataa of Kiffa recorded the highest number of cases in September, with a notable weekly peak during that month in 2020. According to the analysis of the National Institute of Public Health database, cases of viral hemorrhagic fevers were promptly handled. Survey responses and database analysis revealed issues related to data quality and data management mechanisms. These limitations in the surveillance system are likely to be due to insufficient resources and training of the personnel, in particular with regards to data collection and management, which in turn led to incomplete or missing data and invalid data entry. These weak points can be ascribed, at least in part, to financial constraints and inadequate attribution of priority to arboviral diseases. Despite these limitations, disease data generated by the surveillance system were generally reliable. Conclusion: The viral hemorrhagic fever surveillance system in the Assaba region adheres to the organization and functioning of the national viral hemorrhagic fever surveillance system, which is part of the IDSR. The characteristics of utility, simplicity, responsiveness, and flexibility of the viral hemorrhagic fever surveillance system are good, but acceptability and flexibility need further improvement. The earlier the first arboviral human or animal cases are detected, the more likely an active intervention can be organized in response to the emerging epidemic or epizootic and prevent the spread of the disease. An efficient viral surveillance system is the key to reducing the negative impact of arboviral diseases in Assaba region.

Factors associated with COVID-19 in children aged 0 to 15 in Niger, 2020.

On January 30, 2020, the WHO declared COVID-19 a global health emergency. Children were affected in less severe forms. Niger had implemented measures in a context where children were a source of contamination. The aim was to determine the factors associated with COVID-19 in children in Niger from February to August 2020 through an analysis of the national database. We conducted an analytical cross-sectional study including all COVID-19 suspects in the database. We used Excel and Epi Info 7.2.4. software for data extraction and analysis. Frequencies and proportions were calculated, and in a logistic regression, we estimated the ORs of association with their 95% confidence intervals, the factors associated with COVID-19 at the threshold of p<0.05. Of 572 notified cases of suspected COVID-19 in children aged 0-15, 11.36% were positive. The median age of infected children was 10 years [IQR: 5- 13 years]. The male/female sex ratio was 2.1. Children aged 11 to 15 accounted for 49.2%, 61.5% lived in Niamey, 4.6% had comorbidities. The notion of travel was 12.3% and 40% had a notion of contact, 24.4% had a fever, 23.2% had a cough, 18% were hospitalized, and a case-fatality rate of 1.5%. In etiological analysis, the factors associated with COVID-19 were sex ORa=0.51 [0.28-0.93] p=0.028, presence of symptoms ORa=2.29 [1.23-4.25] p=0.008 and notion of contact ORa=0.32 [0.13-0.77] p=0.011. Exposed children were sensitive to COVID-19, and all age groups were affected, with a predominance of males. We recommend barrier measures adapted to young people, and early detection and management of infected children.

[Analysis of national leprosy surveillance data in Mauritania from 2009 to 2019]. / Analyse des données nationales de surveillance de la lèpre en Mauritanie de 2009 à 2019.

Introduction: Leprosy is a chronic infectious disease that mainly affects the skin, mucous membranes and the peripheral nervous system. Its elimination as a public health problem seems to lead to its ignorance and therefore to a risk of late diagnosis. An analysis of leprosy surveillance data in Mauritania was conducted to determine epidemiological trends and clinical forms of reported cases. Material and method: The retrospective study was based on the epidemiological records of leprosy in Mauritania from 2009 to 2019. The diagnosis of leprosy was made on the basis of the diagnostic criteria of the World Health Organization (WHO). Data were analyzed using Epi Info version 7.2.5.0. The frequencies, proportions, and rates were calculated. Results: Over the past 11 years, 164 cases have been notified. Among the notified cases, 96/164 (58.5%) were males and 68/164 (41.5%) females, with a sex ratio of 1.4. The mean age (± standard deviation) was 44.0 ± 17.1 years [range, 9 - 86 years], and the median was 45 years [interquartile range, 32.5; 57.5]. Children under the age of 16 accounted for 9/164 (5.5%). The wilayas (i.e. "regions") of Nouakchott were the most endemic regions in the country. The multibacillary form (MB) represented 109/164 (66.5%) cases among the observed clinical forms. The average annual incidence was 0.3 case/100,000 population for MB and 0.1 case/100,000 for PB (paucibacillary). All reported cases were treated with multidrug therapy. Conclusion: The results of leprosy surveillance showed a persistence of this disease in Mauritania. It is necessary to relaunch leprosy services at all levels in order to continue to reduce the morbidity associated with this disease, and eventually eliminate it from the country.

Epidemiological profile of measles in Niger: analysis of measles case-based surveillance data from 2010 to 2019.

Measles is a rapidly growing disease in the world with 869,770 cases and 207,500 deaths recorded in 2019. Niger continues to record epidemic outbreaks despite the actions taken. This study aims to analyze the national database from 2010 to 2019 to characterize the epidemiology of measles in Niger. This is a descriptive retrospective study. Our sample is exhaustive of suspected and positive measles cases from the database of the department of surveillance and response to epidemics for 10 years. Data extraction and analysis was done using Epi Info 7.2.3.1 software. In our study we found n=11,784 suspected measles cases notified from 2010 to 2019 with 37.2% of positive cases (IgM+). All regions are concerned. The female/male sex ratio was 1.1. The 1-to-5-year age group was the most representative (44.44%); 28.3% received at least one dose of vaccine; 62.22% lived in urban areas. The number of deaths was 225 (1.9%). The proportion of samples received at the laboratory within 3 days is 70.38%. The baseline analysis allowed us to find that all regions recorded cases and deaths with a low vaccination rate of 28.3%. Improved response and immunization strategies are recommended.

Investigation Around Cases of Crimean-Congo Hemorrhagic Fever-Mauritania, 2022.

Background: Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic arbovirosis. Humans are infected by tick bites or contact with blood of infected animals. CCHF can be responsible for severe outbreaks due to human-to-human transmission. Our aims were to increase awareness and promote the search for risk factors and disease monitoring to prevent CCHF epidemic, capacity building, appropriate measures to treat patients, and information for the local population. Methods: During the outbreak of hemorrhagic fever from February to May 2022, blood samples were collected from 88 patients suspected to be infected with the virus. Diagnosis was established by reverse-transcription polymerase chain reaction (RT-PCR) and/or enzyme-linked immunosorbent assay. Results: CCHF was confirmed by RT-PCR in 7 of 88 (8%) patients. Ticks were found in cattle, sheep, or goats in the areas where the subjects resided, with the exception of 1 CCHF-positive patient in close contact with fresh animal meat. Exposure to potential risk factors was found in all patients. The interval between the onset of symptoms and hospital admission was 2-3 days. All 7 patients were admitted to our hospital and treated promptly by blood transfusion. Two patients died. Conclusions: Mortality is high in patients with the hemorrhagic form of CCHF. Disease prevention is necessary by strengthening vector control, avoiding contact and consumption of organic products from diseased animals, and vaccinating animals in areas where the disease is endemic. Furthermore, it is essential to establish management procedures for patients infected with CCHF virus.