[External Quality Assessment of Thick and Thin Blood Smear Slides for the Diagnosis of Malaria in the Lomé and Gulf Health Districts of Togo]. / Évaluation Externe de la Qualité de la Goutte Épaisse/Frottis Sanguin pour le Diagnostic du Paludisme dans les Districts Sanitaires de Lomé et du Golfe au Togo.

Objective: In sub-Saharan Africa where 90% of malaria cases are concentrated, the control of this disease constitutes a major challenge whose diagnosis by thick and thin smear deserves to be exact and reproducible. The purpose of this study is to assess the performance of thick/thin blood smear in order to improve its implementation process. Material and methods: This was a descriptive and analytical study that took place from May to June 2017 and involved participating laboratories (PL) coming from public, liberal and confessional sectors in Lomé. A set of 13 blood smear slides of variable parasite densities (PD) with assigned values (AV) of parasite densities and the Plasmodium species assigned was used. The criterion for establishing the parasite densities compliance interval was assigned values ± 25% and the performance rates were compared to the 80% recommended by the WHO for Africa region. Results: 41.9% (13/31) of the PLs had a compliance rate greater than 80% including four with a performance of 100% for the ability to identify the Plasmodium species. For the parasitaemia < 100/µl, 51.6% of participating laboratories had a performance rate less than 80% and for parasitaemia > 2000/µl, 100% of these laboratories had a performance rate greater than 80%. Conclusion: The evaluated laboratories had insufficient ability for the identification of Plasmodium falciparum and the correct estimation of low parasitaemia. A need to strength the technical skills, adapted to the context of low parasitaemia are essential to improve the biological diagnosis of malaria in Togo.

[Lymphatic filariasis transmission assessment survey in schools three years after stopping mass drug treatment with albendazole and ivermectin in the 7 endemic districts in Togo]. / Enquête d'évaluation de la transmission de la filariose lymphatique en milieu scolaire, 3 ans après l'arrêt du traitement de masse à l'albendazole et à l'ivermectine dans les 7 districts endémiques du Togo.

The aim of this study is to verify the level of transmission of lymphatic filariasis three years after stopping mass drug treatment in the 7 endemic districts in Togo. The survey was conducted in 2012 in Togo's 7 endemic districts grouped into four evaluation units (EU) using the WHO-recommended transmission assessment survey (TAS) protocol. Children aged 6-7 years were screened for Wuchereria bancofti antigen using the immunochromatographic card (ICT) method. A cluster sampling method was used to select eligible children in schools as the net primary-school enrolment ratio is greater than or equal to 75% in each of the four EUs. The number of children and schools to be selected in each EU, the randomization list for the selection of these children and the critical cut-off number of positive cases not to exceed were automatically generated using the Survey Sample Builder (SSB) tool, (NTD Support Center, Atlanta, Ga, USA). For confirmation, positive cases were subsequently tested for microfilaremia using nocturnal thick blood smear and for filarial antigen using Og4C3 antigen ELISA (TropBio ELISA Kit®, Townsville, Queensland, Australia). An EU is considered to have passed the test successfully (it is assumed that transmission can no longer be sustained), when the number of positive cases is below the critical cut-off number set by the SSB, which is roughly equivalent to 2% prevalence. Of the 1 706 children surveyed in Kpendjal-Tone's EU, 1 549 in Binah-Doufelgou's EU, 1 550 in Kozah's EU and the 1 575 in Amou-Haho's EU, 8 (0.46%), 1 (0.08%), 0 (0.00%) and 4 (0.25%) ICT positive cases respectively were detected. The number of positive ICT tests was well below 18, the critical cut number for each of the 4 EUs. All 13 ICT positive cases tested negative for nocturnal microfilaremia and Og4C3 ELISA. We conclude that all four EU passed the TAS with success, and the transmission of Wuchereria bancrofti is no longer likely to be sustained in the 7 endemic districts in Togo 3 years after stopping the MDA. A new TAS will be carried out in 2015, after which, if the results are still good, the country will submit a dossier to WHO for verification of the elimination of lymphatic filariasis.

[Hepatitis B virus serologic status among hospital health care staff in Lome]. / Évaluation de la protection vaccinale contre le virus de l'hépatite B chez le personnel soignant hospitalier à Lomé

To assess the hepatitis B virus (HBV) serologic status of hospital health care personnel in Lome. From June 1 to August 31, 2007, 100 workers vaccinated against HBV and 50 unvaccinated workers participated in this comparative cross-sectional study. The data studied were: age, sex, vaccination status, history of accidental exposure to blood, and enzyme-linked immunoassay results for HBs antigen (Ag), total anti-HBc antibodies (Ab), and anti-HBs Ab. Vaccinated subjects had a mean age of 33.2 ± 8.2 years and unvaccinated subjects of 35.2 ± 9.6 years; their respective sex ratios (M:W) were 2:1 and 3:1. Protective levels (>10 IU/L) of anti-HBs Ab were found in 78% (n = 78) of vaccinated subjects compared with 44% (n = 22) of those unvaccinated. HBs Ag was found in 36% (n = 36) of vaccinated and 56% (n = 28) of unvaccinated subjects. Of subjects previously accidentally exposed to blood, 67% (n = 35) had HBs Ag compared with 30% (n = 29) of those subjects without such exposure. This study has proved the high prevalence of HBs Ag carrier status among health care workers in Lome and confirms the importance of vaccination against HBV.

[White blood cells counts and parasite density in malaria in children aged 6 to 60 months in urban areas of Togo]. / Numération leucocytaire et densité parasitaire dans le paludisme simple chez les enfants âgés de 6 mois à 5 ans en milieu urbain au Togo.

Rational use of the artemisinin-based combination therapies in Togo requires laboratory parasitemia values to confirm suspected malaria. This study was conducted to determine the impact of the measured white blood cell (WBC) count on the determination of malaria parasite density among children younger than 5 years old infected with uncomplicated Plasmodium falciparum in Togo. This cross-sectional study of 267 children from four pediatric centers diagnosed malaria with both thick and thin blood smears and counted WBCs with a hematology analyzer. The parasite densities, calculated with the number of WBCs and estimated with an assumed count of 8,000/µL, were compared with the Wilcoxon matched pairs signed-rank test. The children's median age was 35 months (interquartile range [24-48]), with a sex ratio of 1.32. The median WBC value was 8,300 cells/µL (range: 1,300-24,900 cells/µL). The median parasitemia value calculated with the absolute WBC count was 35,714 (range: 139-48,860 parasites/µL) was not statistically different from that estimated with the assumed value of 8,000 cells/µL - 33 125 parasites/µL (p = 0.564). This study shows that malaria parasite density obtained by assuming 8000 cells/µL does not result in overestimations for children aged 6-59 months.

Nationwide integrated mapping of three neglected tropical diseases in Togo: countrywide implementation of a novel approach.

OBJECTIVE: To conduct a nationwide integrated neglected tropical disease (NTD) prevalence survey to define the need for public health interventions using an innovative mapping protocol. METHODS: Two villages were selected in every peripheral health unit in endemic districts: 29 districts for schistosomiasis and STH, 15 of them for trachoma. In each village, 15 children aged 6-9 years at a randomly selected school were tested. An additional convenience sample of 35 children aged 1-5 years underwent an eye examination for trachoma. This integrated mapping was followed by a 20-cluster trachoma survey in each district that surpassed the WHO-defined threshold of 10% prevalence of trachomatous inflammation-follicular (TF). RESULTS: A total of 1096 villages were surveyed in <6 weeks. The district prevalence of schistosomiasis ranged from 2 to 49% and of STH from 5 to 70%, with prevalence at the village level ranging from 0 to 100% for both diseases. Two districts passed the threshold of 10% for active trachoma, but the cluster survey indicated this was because of misclassification bias and that the real prevalence was <1%. CONCLUSION: Results of this mapping were used by the MoH and partners to plan integrated mass drug administration (MDA). Mass drug administration for trachoma was not implemented as no district passed the threshold requiring public health intervention.