Therapeutic efficacy and tolerability of artemether-lumefantrine for uncomplicated Plasmodium falciparum malaria in Niger, 2020

BACKGROUND

Monitoring therapeutic efficacy is important to ensure the efficacy of artemisinin-based combination therapy (ACT) for malaria. The current first-line treatment for uncomplicated malaria recommended by the National Malaria Control Program in Niger is artemether-lumefantrine (AL). In 2020, an in vivo study was carried out to evaluate clinical and parasitological responses to AL as well as the molecular resistance to the drug in three sentinel sites: Agadez, Tessaoua and Gaya, in Niger.

METHODS

A multi-center, single-arm trial was conducted according to the 28-day World Health Organization (WHO) 2009 therapeutic efficacy study protocol. Children between 6 months and 15 years with confirmed uncomplicated Plasmodium falciparum infection and 1000-200,000 asexual parasites/μL of blood were enrolled and followed up for 28 days. Uncorrected and PCR-corrected efficacy results at day 28 were calculated, and molecular correction was performed by genotyping the msp1, msp2, and glurp genes. The pfk13, pfdhfr, pfdhps, pfcrt and pfmdr genes were analyzed by PCR and Sanger sequencing. The Kaplan-Meier curve assessed parasite clearance.

RESULTS

A total of 255 patients were enrolled in the study. The adequate clinical and parasitological response after PCR correction was 98.9% (95% CI 96.4-101.0%), 92.2% (85.0-98.5%) and 97.1% (93.1-101.0%) in Gaya, Tessaoua and Agadez, respectively. No adverse events were observed. Ten mutations (SNP) were found, including 7 synonyms (K248K, G690G, E691E, E612E, C469C, G496G, P718P) and 3 non-synonyms (N594K, R255K, V714S). Two mutations emerged: N594K and V714S. The R255K mutation detected in Southeast Asia was also detected. The pfdhpsK540E and pfdhfrI164L mutations associated with high levels of resistance are absent. There is a reversal of chloroquine resistance.

CONCLUSION

The study findings indicate that AL is effective and well tolerated for the treatment of uncomplicated malaria in three sites in Niger. The emergence of a pfk13 mutation requires additional testing such as the Ring Stage Assay and CRISPR/Cas9 to confirm the role of these emerging mutations. Trial registration NCT05070520, October 7, 2021.

Plasmodium falciparum kelch13 polymorphisms identified after treatment failure with artemisinin-based combination therapy in Niger

BACKGROUND

Artemisinin-based combination therapy (ACT) is the most effective treatment for malaria, and has significantly reduced morbimortality. Polymorphisms associated with the Plasmodium falciparum Kelch gene (Pfkelch13) have been associated with delayed parasite clearance even with ACT treatment.

METHODS

The Pfkelch13 gene was sequenced from P. falciparum infected patients (n = 159) with uncomplicated malaria in Niger. An adequate clinical and parasitological response (ACPR) was reported in 155 patients. Four (n = 4) patients had treatment failure (TF) that were not reinfections-two of which had late parasitological failures (LPF) and two had late clinical failures (LCF).

RESULTS

Thirteen single nucleotide polymorphisms (SNPs) were identified of which seven were non-synonymous (C469R, T508S, R515T, A578S, I465V, I437V, F506L,), and three were synonymous (P443P, P715P, L514L). Three SNP (C469R, F506L, P715P) were present before ACT treatment, while seven mutations (C469R, T508S, R515T, L514L, P443P, I437V, I465V) were selected by artemether/lumefantrine (AL)-five of which were non-synonymous (C469R, T508S, R515T, I437V, I465V). Artesunate/amodiaquine (ASAQ) has selected any mutation. One sample presented three cumulatively non-synonymous SNPs-C469R, T508S, R515T.

CONCLUSIONS

This study demonstrates intra-host selection of Pfkelch13 gene by AL. The study highlights the importance of LCF and LPF parasites in the selection of resistance to ACT. Further studies using gene editing are required to confirm the potential implication of resistance to ACT with the most common R515T and T508S mutations. It would also be important to elucidate the role of cumulative mutations.

Safety, effectiveness, and adherence of a short and all-oral treatment regimen for the treatment of rifampicin-resistant tuberculosis in Niger: a study protocol of a pragmatic randomised clinical trial with stratified block randomisation

BACKGROUND

Rifampicin-resistant tuberculosis (RR-TB) treatment requires combination treatment, which frequently causes serious adverse events and globally results in not much more than 60% treatment success. In Niger, a high cure rate was obtained with a RR-TB treatment strategy based on a second-line injectable drug (SLID)-containing Short Treatment Regimen (STR), with linezolid replacing the SLID in patients with ototoxicity. Given the availability of novel anti-tuberculosis drugs, WHO recommends all-oral RR-TB treatment. Considering the high level of success with the Niger treatment strategy, it would only be justified to replace it in case robust evidence shows that the WHO all-oral bedaquiline/linezolid (BDQ/LZD)-containing STR (experimental arm) performs better than the Niger RR-TB treatment strategy, (control arm) in terms of safety, effectiveness and adherence.

METHODS

A pragmatic randomised clinical trial (RCT) using stratified block randomisation, conducted between April 2021 and March 2024, prospectively enrols participants diagnosed with RR-TB in one of the four RR-TB units of the nation. Depending of the month in which patients are diagnosed with RR-TB, patients with FQ-susceptible RR-TB are enrolled in either the experimental arm or control arm.

DISCUSSION

To increase the feasibility of conducting a RCT, embedded in routine activities of all Niger's RR-TB Units, we used a creative trial design. We randomised by monthly blocks, whereby the regimen used changes every month, using the month of RR-TB diagnosis as stratifying variable. This approach was deemed feasible for Niger's national tuberculosis programme, as it simplifies the work of the clinicians running the RR-TB units. Our creative design may serve as an example for other national programs. Findings will inform national and international RR-TB treatment guidelines, and will also strengthen the evidence-base on how to develop robust RR-TB treatment regimens.

TRIAL REGISTRATION

Pan African Clinical Trial Register PACTR202203645724919 . Registered on 15 March 2022.

Prevalence of Mutations in the Pfdhfr, Pfdhps, and Pfmdr1 Genes of Malarial Parasites Isolated from Symptomatic Patients in Dogondoutchi, Niger

The effectiveness of artemisinin-based combination therapies (ACTs) depends not only on that of artemisinin but also on that of partner molecules. This study aims to evaluate the prevalence of mutations in the Pfdhfr, Pfdhps, and Pfmdr1 genes from isolates collected during a clinical study. Plasmodium genomic DNA samples extracted from symptomatic malaria patients from Dogondoutchi, Niger, were sequenced by the Sanger method to determine mutations in the Pfdhfr (codons 51, 59, 108, and 164), Pfdhps (codons 436, 437, 540, 581, and 613), and Pfmdr1 (codons 86, 184, 1034, and 1246) genes. One hundred fifty-five (155) pre-treatment samples were sequenced for the Pfdhfr, Pfdhps, and Pfmdr1 genes. A high prevalence of mutations in the Pfdhfr gene was observed at the level of the N51I (84.97%), C59R (92.62%), and S108N (97.39%) codons. The key K540E mutation in the Pfdhps gene was not observed. Only one isolate was found to harbor a mutation at codon I431V. The most common mutation on the Pfmdr1 gene was Y184F in 71.43% of the mutations found, followed by N86Y in 10.20%. The triple-mutant haplotype N51I/C59R/S108N (IRN) was detected in 97% of the samples. Single-mutant (ICS and NCN) and double-mutant (IRS, NRN, and ICN) haplotypes were prevalent at 97% and 95%, respectively. Double-mutant haplotypes of the Pfdhps (581 and 613) and Pfmdr (86 and 184) were found in 3% and 25.45% of the isolates studied, respectively. The study focused on the molecular analysis of the sequencing of the Pfdhfr, Pfdhps, and Pfmdr1 genes. Although a high prevalence of mutations in the Pfdhfr gene have been observed, there is a lack of sulfadoxine pyrimethamine resistance. There is a high prevalence of mutation in the Pfmdr184 codon associated with resistance to amodiaquine. These data will be used by Niger’s National Malaria Control Program to better monitor the resistance of Plasmodium to partner molecules in artemisinin-based combination therapies.

OUP accepted manuscript

BACKGROUND

Outcomes of retreatment for rifampicin-resistant tuberculosis (RR-TB) are rarely reported. We report 'definitive outcomes' after a cascade approach to RR-TB treatment. After a bacteriologically adverse outcome for the 9-months fluoroquinolone-based Short Treatment Regimen (STR), patients were retreated with a bedaquiline-based regimen (BDQ-regimen).

METHODS

A Retrospective cohort study of RR-TB patients treated with the STR during 2012-2019 and retreated with a BDQ-regimen in case of failure or relapse was conducted. Definitive relapse-free cure took into account BDQ-regimen outcomes.

RESULTS

Of 367 patients treated with the STR, 20 (5.4%) experienced failure or relapse. Out of these 20 patients, 14 started a BDQ-regimen, of whom none experienced failure or relapse. Definitive end of treatment outcomes of STR after revising with third-line BDQ-regimen outcomes, 84.7% (311/367) were cured relapse-free, 10.6% (39/367) died during treatment and 3.0% (11/367) were lost to follow-up during treatment with either the STR or BDQ-regimen. Six patients (1.6%; 6/367) with STR failure/relapse died before starting a BDQ-regimen. No patient had definitive treatment failure or relapse and remained without treatment.

CONCLUSIONS

If fluoroquinolone resistance is excluded or rare, it is beneficial to use fluoroquinolone as the core drug for a first RR-TB treatment regimen and to safeguard bedaquiline for those in need of retreatment.

Clinical features and predictors of mortality among hospitalized patients with COVID-19 in Niger

Introduction

COVID-19 has spread across the African continent, including Niger. Yet very little is known about the phenotype of people who tested positive for COVID-19. In this humanitarian crises region, we aimed at characterizing variation in clinical features among hospitalized patients with COVID-19-like syndrome and to determine predictors associated with COVID-19 mortality among those with confirmed COVID-19.

Methods

The study was a retrospective nationwide cohort of hospitalized patients isolated for COVID-19 infection, using the health data of the National Health Information System from 19 March 2020 (onset of the pandemic) to 17 November 2020. All hospitalized patients with COVID-19-like syndrome at admission were included. A Cox-proportional regression model was built to identify predictors of in-hospital death among patients with confirmed COVID-19.

Results

Sixty-five percent (472/729) of patients hospitalized with COVID-19 like syndrome tested positive for SARS-CoV-2 among which, 70 (15%) died. Among the patients with confirmed COVID-19 infection, age was significantly associated with increased odds of reporting cough (adjusted odds ratio [aOR] 1.02; 95% confidence interval [CI] 1.01–1.03) and fever/chills (aOR 1.02; 95% CI 1.02–1.04). Comorbidity was associated with increased odds of presenting with cough (aOR 1.59; 95% CI 1.03–2.45) and shortness of breath (aOR 2.03; 95% CI 1.27–3.26) at admission. In addition, comorbidity (adjusted hazards ratio [aHR] 2.04; 95% CI 2.38–6.35), shortness of breath at baseline (aHR 2.04; 95% CI 2.38–6.35) and being 60 years or older (aHR 5.34; 95% CI 3.25–8.75) increased the risk of COVID-19 mortality two to five folds.

Conclusion

Comorbidity, shortness of breath on admission, and being aged 60 years or older are associated with a higher risk of death among patients hospitalized with COVID-19 in a humanitarian crisis setting. While robust prospective data are needed to guide evidence, our data might aid intensive care resource allocation in Niger.

Determination of administered activities for the treatment of Graves' disease with iodine-131: Proposition of a simplified dosimetric procedure

This prospective study included 35 patients suffering from Graves' disease (GD) clinically and biologically confirmed by endocrinologists, sent to the nuclear medicine department of CHU de Bab El Oued, Algiers for iodine-131 therapy. CHU de Bab El Oued is a tertiary hospital located in the center of the capital Algiers. The aim of this study is to propose a simplified dosimetric procedure which will initiate iodine-131 therapy of GD in particular and hyperthyroidism in general in Niger. The determination of the maximum uptake was performed with a Biodex external probe at 2 h, 4 h, and 24 h after the administration of 3 MBq of liquid iodine-131. The iodine-131 activities were determined using the Marinelli formula with a predefined effective half-life (T_e) of 5 days and subsequently extrapolated half-life with kaleidagraph software. The statistical analysis was performed using an excel sheet and analyzed using the software package Statistica 10 (stat Soft, Tulsa, USA). the male:female gender ratio was1:4.5 and the mean age was 42.56 years (±7.14). The body mass index was within normal range with a value of 25.25 kg²(±0.42) and the mean average thyroid mass was equal to 24.05 (±10.53) g. The mean uptake value at 24 h was 43.24% (±17.68%) meanwhile the maximum uptake value was 46.28 (±21.13%). The estimated effective half-life (T_e) was 5.44 days (±1.96) days which were different from the predefined T_e of 5 days. The mean activity determined with fixed T_e and 24 h uptake was 244.45 (±109.2) MBq and the mean activity calculated with both extrapolated T_e and maximum uptake was 452.22 (±381.9) MBq. Empirical determination of activity in the treatment of GD gives higher activities (1.5 times) to patients than dosimetric methods based on the determination of extrapolated effective half-life.

Correction: Immunogenicity of an oral rotavirus vaccine administered with prenatal nutritional support in Niger: A cluster randomized clinical trial

[This corrects the article DOI: 10.1371/journal.pmed.1003720.].

[Safety and Efficacy of Artemether-Lumefantrine and Artesunate-Amodiaquine in Niger]

This study aims to evaluate the therapeutic efficacy and tolerance of two ACTs widely used for the treatment of uncomplicated malaria due to Plasmodium falciparum in Niger. The study was conducted from September to November 2017, at the Integrated Health Centers of Dogondoutchi and Birni N'Gaouré, in patients aged from 6 months to 15 years, with uncomplicated malaria due to Plasmodium falciparum. They were treated with either Artemether-Lumefantrine (AL) or Artesunate-Amodiaquine (ASAQ). The primary endpoint was the appropriate clinical and parasitological response (RCPA) to D28, after PCR correction. The secondary criteria were the clearing time of fever, parasites, and gametocytes and then the occurrence of adverse events. A total of 459 patients were examined, of whom 312 patients met the inclusion criteria for therapeutic efficacy evaluation. We have followed 299 patients up to J28 including 146 in the AL arm and 153 in the ASAQ arm. After PCR correction at J28, RCPA were 95.8% and 96% (P = 0.7185) for arms AL and ASAQ, respectively, compared to 93.1% and 94.1% respectively before PCR correction (P = 0.7892). The number of patients on AL and ASAQ treatment who developed an adverse reaction were 6 (7.6%) and 23 (28%) respectively. AL and ASAQ associations are effective and well tolerated. No serious adverse event was noted. However, their monitoring must continue to detect possible resistance.

Immunogenicity of an oral rotavirus vaccine administered with prenatal nutritional support in Niger: A cluster randomized clinical trial

BACKGROUND

Nutritional status may play a role in infant immune development. To identify potential boosters of immunogenicity in low-income countries where oral vaccine efficacy is low, we tested the effect of prenatal nutritional supplementation on immune response to 3 doses of a live oral rotavirus vaccine.

METHODS AND FINDINGS

We nested a cluster randomized trial within a double-blind, placebo-controlled randomized efficacy trial to assess the effect of 3 prenatal nutritional supplements (lipid-based nutrient supplement [LNS], multiple micronutrient supplement [MMS], or iron-folic acid [IFA]) on infant immune response (n = 53 villages and 1,525 infants with valid serology results: 794 in the vaccine group and 731 in the placebo group). From September 2015 to February 2017, participating women received prenatal nutrient supplement during pregnancy. Eligible infants were then randomized to receive 3 doses of an oral rotavirus vaccine or placebo at 6-8 weeks of age (mean age: 6.3 weeks, 50% female). Infant sera (pre-Dose 1 and 28 days post-Dose 3) were analyzed for anti-rotavirus immunoglobulin A (IgA) using enzyme-linked immunosorbent assay (ELISA). The primary immunogenicity end point, seroconversion defined as ≥3-fold increase in IgA, was compared in vaccinated infants among the 3 supplement groups and between vaccine/placebo groups using mixed model analysis of variance procedures. Seroconversion did not differ by supplementation group (41.1% (94/229) with LNS vs. 39.1% (102/261) with multiple micronutrients (MMN) vs. 38.8% (118/304) with IFA, p = 0.91). Overall, 39.6% (n = 314/794) of infants who received vaccine seroconverted, compared to 29.0% (n = 212/731) of infants who received placebo (relative risk [RR]: 1.36; 95% confidence interval [CI]: 1.18, 1.57, p < 0.001). This study was conducted in a high rotavirus transmission setting. Study limitations include the absence of an immune correlate of protection for rotavirus vaccines, with the implications of using serum anti-rotavirus IgA for the assessment of immunogenicity and efficacy in low-income countries unclear.

CONCLUSIONS

This study showed no effect of the type of prenatal nutrient supplementation on immune response in this setting. Immune response varied depending on previous exposure to rotavirus, suggesting that alternative delivery modalities and schedules may be considered to improve vaccine performance in high transmission settings.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02145000.

Rotavirus vaccine efficacy up to 2 years of age and against diverse circulating rotavirus strains in Niger: Extended follow-up of a randomized controlled trial

BACKGROUND

Rotavirus vaccination is recommended in all countries to reduce the burden of diarrhea-related morbidity and mortality in children. In resource-limited settings, rotavirus vaccination in the national immunization program has important cost implications, and evidence for protection beyond the first year of life and against the evolving variety of rotavirus strains is important. We assessed the extended and strain-specific vaccine efficacy of a heat-stable, affordable oral rotavirus vaccine (Rotasiil, Serum Institute of India, Pune, India) against severe rotavirus gastroenteritis (SRVGE) among healthy infants in Niger.

METHODS AND FINDINGS

From August 2014 to November 2015, infants were randomized in a 1:1 ratio to receive 3 doses of Rotasiil or placebo at approximately 6, 10, and 14 weeks of age. Episodes of gastroenteritis were assessed through active and passive surveillance and graded using the Vesikari score. The primary endpoint was vaccine efficacy of 3 doses of vaccine versus placebo against a first episode of laboratory-confirmed SRVGE (Vesikari score ≥ 11) from 28 days after dose 3, as previously reported. At the time of the primary analysis, median age was 9.8 months. In the present paper, analyses of extended efficacy were undertaken for 3 periods (28 days after dose 3 to 1 year of age, 1 to 2 years of age, and the combined period 28 days after dose 3 to 2 years of age) and by individual rotavirus G type. Among the 3,508 infants included in the per-protocol efficacy analysis (mean age at first dose 6.5 weeks; 49% male), the vaccine provided significant protection against SRVGE through the first year of life (3.96 and 9.98 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 60.3%, 95% CI 43.6% to 72.1%) and over the entire efficacy follow-up period up to 2 years of age (2.13 and 4.69 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 54.7%, 95% CI 38.1% to 66.8%), but the difference was not statistically significant in the second year of life. Up to 2 years of age, rotavirus vaccination prevented 2.56 episodes of SRVGE per 100 child-years. Estimates of efficacy against SRVGE by individual rotavirus genotype were consistent with the overall protective efficacy. Study limitations include limited generalizability to settings with administration of oral polio virus due to low concomitant administration, limited power to assess vaccine efficacy in the second year of life owing to a low number of events among older children, potential bias due to censoring of placebo children at the time of study vaccine receipt, and suboptimal adapted severity scoring based on the Vesikari score, which was designed for use in settings with high parental literacy.

CONCLUSIONS

Rotasiil provided protection against SRVGE in infants through an extended follow-up period of approximately 2 years. Protection was significant in the first year of life, when the disease burden and risk of death are highest, and against a changing pattern of rotavirus strains during the 2-year efficacy period. Rotavirus vaccines that are safe, effective, and protective against multiple strains represent the best hope for preventing the severe consequences of rotavirus infection, especially in resource-limited settings, where access to care may be limited. Studies such as this provide valuable information for the planning of national immunization programs and future vaccine development.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02145000.

Laboratory organisation and management of SARS-CoV-2 infection in Niger, West Africa

Background

As the coronavirus disease 2019 (COVID-19) pandemic unfolds, laboratory services have been identified as key to its containment. This article outlines the laboratory organisation and management and control interventions in Niger.

Intervention

The capitol city of Niger, Niamey, adopted a ‘National COVID-19 Emergency Preparedness and Response Plan’ to strengthen the preparedness of the country for the detection of severe acute respiratory syndrome coronavirus-2. Laboratory training and diagnostic capacity building were supported by existing active clinical and research laboratories for more rapid and practicable responses. The National Reference Laboratory for Respiratory Viruses located at the Centre de Recherche Médicale et Sanitaire was designated as the reference centre for COVID-19 testing. The national plan for COVID-19 testing is being gradually adopted in other regions of the country in response to the rapidly evolving COVID-19 emergency and to ensure a more rapid turn-around time.

Lessons learnt

After the decentralisation of COVID-19 testing to other regions of the country, turn-around times were reduced from 48–72 h to 12–24 h. Reducing turn-around times allowed Niger to reduce the length of patients’ stays in hospitals and isolation facilities. Shortages in testing capacity must be anticipated and addressed. In an effort to reduce risk of shortages and increase availability of reagents and consumables, Niamey diversified real-time reverse transcriptase–polymerase chain reaction kits for severe acute respiratory syndrome coronavirus-2 detection.

Recommendations

Continued investment in training programmes and laboratory strategy is needed in order to strengthen Niger’s laboratory capacity against the outbreak.

Extended Follow-up From a Randomized Clinical Trial of Routine Amoxicillin in the Treatment of Uncomplicated Severe Acute Malnutrition in Niger

This study is an extended follow-up of a randomized clinical trial of routine amoxicillin use for infants experiencing uncomplicated severe acute malnutrition in Niger.

[Epidemiological, clinical and evolutionary profile of patients with tuberculosis at the Regional Hospital of Maradi, Republic of the Niger]

Introduction

Il s'agissait de décrire le profil épidémiologique, clinique et évolutif des patients suivis pour tuberculose au Centre Hospitalier Régional de Maradi.

Méthodes

Nous avions mené une étude rétrospective, descriptive et analytique à partir des dossiers des patients suivis pour tuberculose du 1^er janvier 2015 au 31 décembre 2017.

Résultats

Au total 595 patients ont été suivis dont 406 hommes (68,24%) pour 189 femmes (31,76%) et une prévalence de 27,71%. L'âge moyen était de 42,3 ans avec des extrêmes de 13 mois à 85 ans. 70,5% des patients provenaient du milieu urbain. Les commerçants représentaient 36,9% des cas. La recherche bactériologique était positive dans 64,7% des cas. Les signes fonctionnels étaient représentés par: la toux (99,5%), la fièvre (79,5%), et la douleur thoracique. La tuberculose pulmonaire avait représenté 78,7%. Le succès thérapeutique a été 81,28%. La prévalence du VIH était de 13,6% et une létalité de 10,42% dont 40,4% des patients décédés avaient une co-infection TB/VIH.

Conclusion

Avec 10,42% de décès, la tuberculose demeure un fléau dans les pays à faible revenu. L'infection à VIH/SIDA a négativement influencé ces décès au cours de cette étude. La recherche des facteurs de co-morbidités chez tout patient tuberculeux devrait être systématique afin d'améliorer leur prise en charge globale.

OC 8721 WANECAM II – A CLINICAL TRIAL PROGRAMME TO ASSESS SAFETY, EFFICACY AND TRANSMISSION-BLOCKING PROPERTIES OF A NEW ANTIMALARIAL KAF156 (GANAPLACIDE) IN UNCOMPLICATED MALARIA IN WEST AND CENTRAL AFRICA

Background

Despite major progress in the past decade, malaria remains a major public health problem in sub-Saharan Africa. West and Central Africa account for nearly 2/3 of the burden currently attributable to falciparum malaria. Artemisinin-based combination therapies (ACT) are a cornerstone of our strategy for controlling and eventually eliminating malaria. However, reduced responsiveness/resistance to artemisinin derivatives and to ACTs, an increasing problem in South-East Asia is a major concern. It is of utmost importance to develop new antimalarial drugs from novel chemical classes that can replace ACTs. KAF156, an imidazolepiperazine, is a leading candidate in the antimalarial drug development pipeline. Combination of KAF156 with a Solid Dispersion Formulation of lumefantrine (LUM-SDF) is expected to be fast acting, fully curative, improve patient adherence and can potentially reduce malaria transmission.

Methods

WANECAM II proposes to advance the clinical development of KAF156 through clinical trials in adults and children, with integrated capacity building and infrastructure development activities. The trial programme will be undertaken in the context of networking, team-building, leadership development and community engagement schemes that will involve intra-European, European-African and intra-African collaborative activities. WANECAM II will accelerate the clinical study of children less than 2 years of age which are the key target for new antimalarial treatments.

Results

By the end of the project, the results are expected to contribute to the registration of KAF156/LUM-SDF through stringent regulatory health authorities, increase biomedical research capacity in the consortium and effectively promote networking among the respective teams. A new clinical research team in Niger, a grossly underrepresented country in the African research landscape, will be developed and further increase capacity and infrastructure in the consortium.

Conclusion

Providing a new antimalarial drug combination that does not contain an artemisinin derivative and is effective against resistant P. falciparum strains as well as gametocytes and that is likely to be taken in 3 or fewer single doses will be a major advance in the field. The new combination of KAF156 with LUM-SDF is expected to provide such major advance upon successful conclusion of the WANECAM II project.

Single-dose oral ciprofloxacin prophylaxis as a response to a meningococcal meningitis epidemic in the African meningitis belt: A 3-arm, open-label, cluster-randomized trial

BACKGROUND

Antibiotic prophylaxis for contacts of meningitis cases is not recommended during outbreaks in the African meningitis belt. We assessed the effectiveness of single-dose oral ciprofloxacin administered to household contacts and in village-wide distributions on the overall attack rate (AR) in an outbreak of meningococcal meningitis.

METHODS AND FINDINGS

In this 3-arm, open-label, cluster-randomized trial during a meningococcal meningitis outbreak in Madarounfa District, Niger, villages notifying a suspected case were randomly assigned (1:1:1) to standard care (the control arm), single-dose oral ciprofloxacin for household contacts within 24 hours of case notification, or village-wide distribution of ciprofloxacin within 72 hours of first case notification. The primary outcome was the overall AR of suspected meningitis after inclusion. A random sample of 20 participating villages was enrolled to document any changes in fecal carriage prevalence of ciprofloxacin-resistant and extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae before and after the intervention. Between April 22 and May 18, 2017, 49 villages were included: 17 to the control arm, 17 to household prophylaxis, and 15 to village-wide prophylaxis. A total of 248 cases were notified in the study after the index cases. The AR was 451 per 100,000 persons in the control arm, 386 per 100,000 persons in the household prophylaxis arm (t test versus control p = 0.68), and 190 per 100,000 persons in the village-wide prophylaxis arm (t test versus control p = 0.032). The adjusted AR ratio between the household prophylaxis arm and the control arm was 0.94 (95% CI 0.52-1.73, p = 0.85), and the adjusted AR ratio between the village-wide prophylaxis arm and the control arm was 0.40 (95% CI 0.19‒0.87, p = 0.022). No adverse events were notified. Baseline carriage prevalence of ciprofloxacin-resistant Enterobacteriaceae was 95% and of ESBL-producing Enterobacteriaceae was >90%, and did not change post-intervention. One limitation of the study was the small number of cerebrospinal fluid samples sent for confirmatory testing.

CONCLUSIONS

Village-wide distribution of single-dose oral ciprofloxacin within 72 hours of case notification reduced overall meningitis AR. Distributions of ciprofloxacin could be an effective tool in future meningitis outbreak responses, but further studies investigating length of protection, effectiveness in urban settings, and potential impact on antimicrobial resistance patterns should be carried out.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02724046.

Efficacy of a Low-Cost, Heat-Stable Oral Rotavirus Vaccine in Niger

BACKGROUND

Each year, rotavirus gastroenteritis is responsible for about 37% of deaths from diarrhea among children younger than 5 years of age worldwide, with a disproportionate effect in sub-Saharan Africa.

METHODS

We conducted a randomized, placebo-controlled trial in Niger to evaluate the efficacy of a live, oral bovine rotavirus pentavalent vaccine (BRV-PV, Serum Institute of India) to prevent severe rotavirus gastroenteritis. Healthy infants received three doses of the vaccine or placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis were assessed through active and passive surveillance and were graded on the basis of the score on the Vesikari scale (which ranges from 0 to 20, with higher scores indicating more severe disease). The primary end point was the efficacy of three doses of vaccine as compared with placebo against a first episode of laboratory-confirmed severe rotavirus gastroenteritis (Vesikari score, ≥11) beginning 28 days after dose 3.

RESULTS

Among the 3508 infants who were included in the per-protocol efficacy analysis, there were 31 cases of severe rotavirus gastroenteritis in the vaccine group and 87 cases in the placebo group (2.14 and 6.44 cases per 100 person-years, respectively), for a vaccine efficacy of 66.7% (95% confidence interval [CI], 49.9 to 77.9). Similar efficacy was seen in the intention-to-treat analyses, which showed a vaccine efficacy of 69.1% (95% CI, 55.0 to 78.7). There was no significant between-group difference in the risk of adverse events, which were reported in 68.7% of the infants in the vaccine group and in 67.2% of those in the placebo group, or in the risk of serious adverse events (in 8.3% in the vaccine group and in 9.1% in the placebo group); there were 27 deaths in the vaccine group and 22 in the placebo group. None of the infants had confirmed intussusception.

CONCLUSIONS

Three doses of BRV-PV, an oral rotavirus vaccine, had an efficacy of 66.7% against severe rotavirus gastroenteritis among infants in Niger. (Funded by Médecins sans Frontières Operational Center and the Kavli Foundation; ClinicalTrials.gov number, NCT02145000 .).

[Evaluation of the benefit of different complementary exams in the search for a TB diagnosis algorithm for HIV patients put on ART in Niamey, Niger]

In Niger, the tuberculosis (TB) screening among people living with human immunodeficiency virus (HIV) (PLHIV) is nonsystematic and the use of additional tests is very often limited. The objective of this research is to evaluate the performance and the cost-effectiveness of various paraclinical testing strategies of TB among adult patients with HIV, using available tests in routine for patients cared in Niamey. This is a multicentric prospective intervention study performed in Niamey between 2010 and 2013. TB screening has been sought in newly diagnosed PLHIV, before ART treatment, performing consistently: a sputum examination by MZN (Ziehl-Nielsen staining) and microscopy fluorescence (MIF), chest radiography (CR), and abdominal ultrasound. The performance of these different tests was calculated using sputum culture as a gold standard. The various examinations were then combined in different algorithms. The cost-effectiveness of different algorithms was assessed by calculating the money needed to prevent a patient, put on ART, dying of TB. Between November 2010 and November 2012, 509 PLHIV were included. TB was diagnosed in 78 patients (15.3%), including 35 pulmonary forms, 24 ganglion, and 19 multifocal. The sensitivity of the evaluated algorithms varied between 0.35 and 0.85. The specificity ranged from 0.85 to 0.97. The most costeffective algorithm was the one involving MIF and CR. We recommend implementing a systematic and free direct examination of sputum by MIF and a CR for the detection of TB among newly diagnosed PLHIV in Niger.

High efficacy of first-line ART in a West African cohort, assessed by dried blood spot virological and pharmacological measurements

OBJECTIVES

The objectives of this study were to determine the rate of viral success in HIV-infected patients on first-line ART by the assessment of dried blood spot (DBS) viral load (VL) and to assess the performance of DBS sampling for VL measurement, genotypic resistance and antiretroviral concentration determinations.

METHODS

HIV-infected patients treated for >1 year with first-line ART in Niamey, Niger were included. VL based on nucleic acid sequence-based amplification (NASBA) assay (limit of quantification <800 copies/mL) was measured on DBS capillary samples. Resistance genotype was assessed for all detectable VLs (limit of detection >100 copies/mL); antiretroviral concentrations were interpreted using standard plasma cut-offs after extrapolation of blood to plasma results. Median (IQR) results are presented.

RESULTS

Two hundred and eighteen patients (61% women), aged 41 (34-46) years, with 138 (56-235) CD4 cells/mm³ at baseline were included. After 4 (2-6) years of follow-up under therapy, CD4 gain was +197 (98-372) cells/mm³; 81% had VL <800 copies/mL. Antiretroviral concentrations were adequate in 87% of patients and nevirapine/efavirenz concentrations were related to viral success (P < 0.001). DBS genotypic resistance amplification succeeded in 71% of failing patients: NRTI drug resistance mutations were identified in 73% including resistance to lamivudine/emtricitabine (67%), abacavir (30%) and tenofovir (21%); and NNRTI drug resistance mutations were identified in 82% including resistance to rilpivirine (39%) and etravirine (15%).

CONCLUSIONS

This study demonstrated a good response after 4 years of first-line ART in Niger. Adherence was high, according to antiretroviral concentrations, and the majority of failures were explained by selection of drug resistance mutations detected in the DBS genotype. Using DBS might improve the assessment of ART failure in HIV-infected patients in low-income countries.

Molecular characterization of hepatitis B virus from chronically-infected patients in Niamey, Niger

OBJECTIVES

In Niger, 65% of hepatocarcinoma and 75% of cirrhosis cases were due to hepatitis B virus (HBV). We studied the genotypic characteristics of HBsAg in chronically HBV-infected patients in Niamey.

METHODS

We studied prospectively HBV genotypic patterns among hospitalized patients with HBV infection in the National Hospital of Niamey, Niger. Patients were screened for hepatitis B surface antigen (HBsAg) and HBV genotyping was performed on the HBsAg-positive patients.

RESULTS

In this study, we have confirmed the predominance of the HBV genotype E (HBV-E) in Niger and have identified 2 recombinant forms including HBV-E/D and HBV-A3/E reported previously among blood donors in Niger and Ghana, respectively. Amino acid substitutions found in HBV sequences obtained here included P120T, S143L, G145A and A194T. These substitutions were characterized as being associated with modified antigenicity and, notably, with impaired serological detection of HBsAg, while the A194T variant was found to have a controversial role in reduced susceptibility to tenofovir.

CONCLUSIONS

We have identified two recombinant HBV forms and rare genotypic patterns in Niger that may affect hepatitis B surface antigen antigenicity, and improve current knowledge of epidemiological, clinical and virological patterns of hepatitis B in this country.

Routine Amoxicillin for Uncomplicated Severe Acute Malnutrition in Children

BACKGROUND

High-quality evidence supporting a community-based treatment protocol for children with severe acute malnutrition, including routine antibiotic use at admission to a nutritional treatment program, remains limited. In view of the costs and consequences of emerging resistance associated with routine antibiotic use, more evidence is required to support this practice.

METHODS

In a double-blind, placebo-controlled trial in Niger, we randomly assigned children who were 6 to 59 months of age and had uncomplicated severe acute malnutrition to receive amoxicillin or placebo for 7 days. The primary outcome was nutritional recovery at or before week 8.

RESULTS

A total of 2412 children underwent randomization, and 2399 children were included in the analysis. Nutritional recovery occurred in 65.9% of children in the amoxicillin group (790 of 1199) and in 62.7% of children in the placebo group (752 of 1200). There was no significant difference in the likelihood of nutritional recovery (risk ratio for amoxicillin vs. placebo, 1.05; 95% confidence interval [CI], 0.99 to 1.12; P=0.10). In secondary analyses, amoxicillin decreased the risk of transfer to inpatient care by 14% (26.4% in the amoxicillin group vs. 30.7% in the placebo group; risk ratio, 0.86; 95% CI, 0.76 to 0.98; P=0.02).

CONCLUSIONS

We found no benefit of routine antibiotic use with respect to nutritional recovery from uncomplicated severe acute malnutrition in Niger. In regions with adequate infrastructure for surveillance and management of complications, health care facilities could consider eliminating the routine use of antibiotics in protocols for the treatment of uncomplicated severe acute malnutrition. (Funded by Médecins sans Frontières Operational Center Paris; ClinicalTrials.gov number, NCT01613547.).

Prevalence of Bordetella infection in a hospital setting in niamey, niger

Bordetella pertussis still poses an important health threat in developing countries. In Niger, notified pertussis cases are few despite the low diphtheria-tetanus-pertussis/pentavalent vaccine coverage. We aimed to estimate the prevalence of B. pertussis in children aged <5 years consulting at a pediatric ward. A 5-month study in 2011 recruited 342 children with respiratory symptoms at the National Hospital of Niamey. Nasopharyngeal aspirates were tested by culture and real-time polymerase chain reaction. Overall, 34 (11.2%) of the 305 available nasopharyngeal aspirates tested by real-time polymerase chain reaction were positive for a Bordetella spp., with an estimated prevalence of 8.2 cases per 1000 children aged <5. None was notified to the surveillance network. A single specimen was positive on culture. This study, the first to provide laboratory-confirmed data on pertussis in Niger, highlights the need to sensitize health care personnel to actively notify clinical cases and to integrate laboratory diagnosis in the existing surveillance system.

[Amyotrophic Lateral Sclerosis (ALS) in the 10 last years in CHU Campus of Lomé (TOGO)]

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease that causes damage of upper motor neuron and lower motor neuron. Our objective was to describe the incidence and demographic characteristics of ALS and to analyze its diagnosis and management in Togo.

MATERIALS AND METHODS

A retrospective and descriptive study of patient's observations was conducted in the department of neurology of the teaching hospital in Lomé during a 10 years period (2000 to 2009). The diagnosis of ALS was made according to the clinical classification of El Escorial.

RESULTS

5 cases of ALS were diagnosed, representing 0.049% of the hospitalizations in the department of neurology. The average age of patients was 49 years [range: 24 - 67 years] and the average evolution of the disease was 17.6 months [range: 6 - 36 months]. All the patients were men. The treatment was symptomatic in every case. Treatment with Riluzole was not delivered. During the follow-up, one patient died from respiratory complications.

CONCLUSION

The El Escorial criteria should be made more accessible for a larger audience, as the availability and classification of care management relies heavily on diagnosed cases, namely early diagnosis.

[Severe burn due to sulfuric acid: a report case at the National Hospital of Niamey]

Sulfuric acid is easy to obtain and leads to severe caustic burn. Caustic burns are increasingly common in homicides and suicide. We reported a case of sulfuric acid burn due to a family criminal act. Immediate skin washout was performed and avoided many complications like eyes lesion or their destruction. The skin lesion evolved in different stages of caustic burns: necrosis, tissue mortification then retractile and keloid scar. The treatment duration was 32 months.

[Preparedness for influenza A/H5N1 pandemic in Niger: a study on health care workers' knowledge and global organization of health activities]

Dans les pays industrialisés, l’émergence de virus influenza à potentiel pandémique a suscité des réactions à la mesure de la menace que représentent ces agents infectieux. Cependant, à l’heure de la mondialisation, le contrôle des épidémies repose tout autant sur une coordination mondiale efficace des moyens de lutte que sur une préparation des systèmes de santé nationaux du Nord et du Sud, au centre desquels se trouvent les personnels soignants. Notre étude a pris place dans le principal hôpital nigérien, l’Hôpital national de Niamey. L’objectif était d’évaluer les connaissances des professionnels de soins en matière de pandémie grippale et de contrôle du risque infectieux. Sur la base d’un questionnaire, nous avons interrogé 178 soignants, médicaux et paramédicaux. Cette étude — la première à notre connaissance à explorer ces questions dans le contexte africain — a d’abord mis en lumière une certaine maîtrise des connaissances théoriques sur la grippe aviaire par les soignants. Cependant, au-delà des savoirs théoriques, l’enquête a également permis d’identifier des limites importantes compromettant les capacités de prévention et de lutte contre une pandémie grippale, notamment en termes d’organisation des soins et de contrôle du risque infectieux hospitalier.

[Snake bites in the emergency unit of Niamey National Hospital, Niger]

This study was aimed at assessing envenomations caused by snakebite in Niamey National Hospital, between July 2005 and September 2006. We included 53 victims of snakebites. The wounded distribution indicated more wounded males than females (sex ratio = 1.78:1). The mean age was 29 ± 17 years. September to November seemed a period of higher risk. The snake was not identified in 60% of the cases. The bite occurred during March in 43% of the cases. Clinically, 6% of the patients showed no signs of envenomation and 7% presented bleeding disorders; 88% of the patients did not receive anti-venom. The lethality rate was 15%.

Rabies exposure in international travelers: do we miss the target?

BACKGROUND

Little data exist about the spatial distribution of the risk for travelers of being injured by a potentially rabid animal.

METHODS

Over the last 14 years, animal-associated injuries in 424 international travelers presenting to a travel medicine clinic in Marseille, southern France, were investigated.

RESULTS

The majority of cases were reported from North Africa (41.5%) and Asia (22.2%). Most countries where at-risk injuries occurred (Algeria, Morocco, Tunisia, Thailand, and Turkey) were those for which travelers do not usually seek advice at a specialized travel clinic, because these countries are not at risk for specific travel-associated diseases like malaria or yellow fever. The probability of travelers being attacked by each animal species varied significantly according to the destination country. Dogs were more frequently involved in Algeria, cats in Tunisia and the Middle East, and non-human primates in sub-Saharan Africa, Madagascar, and Asia.

CONCLUSIONS

We suggest that rabies pre-exposure vaccination should be offered to individuals traveling regularly to North Africa to visit their relatives and who are at high risk of exposure to potentially rabid animal attacks. Pre-travel advice when addressing rabies prevention should consider the specific epidemiology of animal-related injuries in the traveled country, as well as the traveler's characteristics. Travelers should be advised about which species of animal are potentially aggressive in their destination country so that they can more easily avoid risk-contacts.

[Plasmodium falciparum chloroquine and pyrimethamine resistance monitoring network with molecular tools in the Niger River valley, Republic of Niger]

Plasmodium falciparum resistance to chloroquine first arose in Africa 25 years ago. Nowadays most of African malaria control programmes have switched their first-line treatment of uncomplicated malaria cases towards artemisinin derivatives combination. After WHO guidelines, a survey network for malaria treatment resistance has been set up in the Niger valley around Niamey since December 2004. The association of the Niger national malaria control programme with the CERMES research center allowed collecting of samples from both health centers and hospitals of this region. Blood finger-pricks on filter papers were tested for detection of plasmodial antigen in health center without biological diagnosis capacity. Specimens found positive either in hospital laboratory or by using antigen method were tested by PCR/RFLP to detect K76T mutations on the pfcrt gene and S108N mutation on the pfdhfr gene. This simple procedure allows the screening of a large number of specimens. Moreover, a spatial distribution of mutations and evidence of resistance clusters were searched integrating the data in a geographic information system. The 76T mutation of pfcrt and 108N of pfdhfr were respectively found in 50.8% and 57% of the specimens tested. No statistically significant difference was found according to the level of sanitary formations or the age of the patients. No resistance cluster was identified and the prevalence of mutation seems homogeneous in the zone. By completing the clinical efficacy studies we think that our simple method for collecting and testing blood samples associated with clinical efficacy studies may be useful for building a network of malaria drug resistance in Africa.

Mefloquine versus 3-day oral quinine–clindamycin in uncomplicated imported falciparum malaria

In this open randomized trial comparing 3-day oral quinine-clindamycin versus standard mefloquine regimen for uncomplicated imported falciparum malaria, mefloquine treatment was associated with a higher risk of discontinuation of the treatment (RR=1.8, 95% CI [1.1-2.8]) related to mainly mild gastrointestinal adverse drug events. The poor tolerability of mefloquine sets a question mark against its use in outpatients.

[Prevalence of cryptosporidiosis in pediatric hospital patients in Niamey, Niger]

No data has been published, so far about the prevalence of cryptosporidiosis among children in Niger; a landlocked country of West Africa where malnutrition and diarrhoea are two major public health issues. The aim of the present study was to get a first evaluation of the prevalence of Cryptosporidium sp in the stools of hospitalized children in the National Hospital of Niamey (NHN) where we carried out a prospective descriptive study involving all children younger than 5 years of age in the paediatric department between February 21st and May 22nd, 2004. Direct stool examination and Ritchie technique were systematically performed, and evidence of Cryptosporidium oocysts was looked for by means of a smear from the sediment which was stained by the modified Ziehl-Neelsen technique. The weight/age ratio was calculated and analyzed with the Epi-Info software, based on the reference population defined by the US National Center for Health Statistics (NCHS). Malnutrition was defined as a weight/age ratio more than 2 SD below the NCHS's reference population. Malnutrition was considered moderate between -2 and -3 SD and severe below 3 SD. In the 3 months study 220 children were included (sex ratio = 1.18 and mean age = 20 months) showing that 65% of the children were suffering from malnutrition (moderate = 17.3%, severe = 47%). Diarrhoea was reported in 51.8% of the children. Cryptosporidium oocysts were detected in 12/220 children (5.5% of the studied population) and 7/114 (6. 1%) of those children were suffering from diarrhoea. 10 (83%) out of the 12 infected children were malnourished. This was the first study ever conducted in the paediatric department of the Niamey hospital, and it showed evidence of a 5.5% prevalence of cryptosporidiosis in the overall studied population, versus 6.1% among children with diarrhoea. 5 children without diarrhoea and 2 children under 6 months were also infected. Another study based on a larger number of patients would be necessary to address the impact of rainfall distribution on the incidence of the disease.

Molecular study of microsporidiosis due to Enterocytozoon bieneusi and Encephalitozoon intestinalis among human immunodeficiency virus-infected patients from two geographical areas: Niamey, Niger, and Hanoi, Vietnam

Microsporidiosis cases due to Enterocytozoon bieneusi and Encephalitozoon intestinalis are emerging opportunistic infections associated with a wide range of clinical syndromes in humans. The aim of this study was to specify microsporidial epidemiology in two different geographical areas. From November 2004 to August 2005, 228 and 42 stool samples were collected in Niamey, Niger, and Hanoi, Vietnam, respectively. Screening for microsporidia was performed using UV-light microscopy. Detection was confirmed by molecular biology using two methods specific for E. bieneusi and E. intestinalis. All samples positive for E. bieneusi were subjected to genotyping. In this study, we found high prevalences of microsporidiosis among human immunodeficiency virus-infected patients, 10.5% and 9.5%, respectively, in Niamey and Hanoi. These levels of prevalence are similar to those recorded in European countries before highly active antiretroviral therapy was introduced. In the samples positive for E. bieneusi, we found seven distinct genotypes, including two genotypes not previously described. The E. bieneusi genotype distributions in the two geographical areas suggest different routes of infection transmission, person-to-person in Niger and zoonotic in Vietnam.

Field-based evidence for the linkage of pfcrt and pfdhfr drug-resistant malaria genotypes and clinical profiles of severe malaria in Niger

Drug resistance has been shown to increase malaria mortality and morbidity in both community- and hospital-based studies. We investigated the association between two Plasmodium falciparum drug resistance-related molecular markers and clinical profiles of severe malaria in children hospitalised in Niger. PCR-RFLP analysis showed that the codon 108 mutation of the pfdhfr gene was positively linked to severe malarial anaemia. These findings are consistent with persistent parasite infection leading to unbalanced anaemia in young children. No significant relationship was found between the molecular markers and hypoglycaemia or hyperparasitaemia. Conversely, the pfcrt T76 mutation was found to be negatively associated with cerebral malaria and neurological symptoms, such as convulsions and coma. These results have implications for the strain-specific virulence hypothesis and for parasite fitness and evolution. Our findings are discussed in regard to the local malaria transmission level.

[The treatment of lower limb varices by stripping and cross sectioning of the saphenous vein at the National Hospital of Niamey: 31 operated limbs]

OBJECTIVE

The authors reported the results of surgical procedure of lower limbs varicose (LLV) by stripping and crossectomy of saphenous vein at the National hospital of Niamey.

METHODS

It is a prospective study during 5 years and half from January 2001 to June 2006. It concerned the all the patients with LLV who underwent a stripping-crossectomy of the great saphenous vein (GVS) and short saphenous vein (SSV) and elastic stocking. The anaes's clinical classification is used.

RESULTS

The series included 27 patients (31 limbs): 20 males and 7 females (Ratio: 2.8). The average age was 32.4 years (ranged: 21 to 58 years). The mean duration of symptoms was 4.2 years (ranged: 3 to 12 years). According the ANAES's classification we found 63% of patients in stage B, and 37% in stage C. We performed 35 stripping crossectomy (28 for GSV and 7 for SSV) with avulsions accessory veins in 6 cases (14%), incompetent perforator ligature in 2 cases (4.6%) and complementary sclerotherapy in 19 cases (61.3%). The postoperative complications including haematomas (9.7%), wound infections (6.5%) and paraesthesia of saphenous nerve (6.5%) were subsequently resolved with treatment. The mean duration of hospitalization was 11 days (ranged: 4 to 18 days). After a mean follow-up period of 3 years (ranged: 6 months to 6 years) the recurrent varices rate was 6.5% (2 cases) due to leg perforators in 1 case/2 and 4 cases (9.7%) of residual ankle oedema.

CONCLUSION

The LLV concerned young people. The results were good and recurrent rate is low after stripping and crossectomy for varicose stage B and C according ANAES's classification. The surgical procedure needed minute clinical and paraclinical assessment.

Genetic diversity and structure of African Plasmodium falciparum populations in urban and rural areas

The genetic variability and population structure of Plasmodium falciparum are key factors in malaria control strategies. Studies have suggested no P. falciparum population structure although linkage disequilibrium was observed in some African areas. We have assessed length polymorphism at 6-22 microsatellites in four urban and rural sites (Djibouti, Dakar, Niamey, and Zouan-Hounien, n = 240 blood samples). Results have shown a P. falciparum population structure in Africa (Fst = 0.17-0.24), lower genetic diversity in Djibouti (He = 0.53) than in the other sites (He = 0.73-0.76), and 3) significant linkage disequilibrium in Djibouti. These results could be related to geographic isolation and low flow of parasites between sites. They also suggest a potential effect of rural suburbs to generate genetic diversity in towns. This could affect the dispersal of selected drug resistance and should be considered when adapting urban malaria control strategies.

Treatment of imported malaria in adults: a multicentre study in France

BACKGROUND

Data about anti-malarial drugs prescription practices in Europe and the safety of imported malaria treatments are scanty. In 1999, a French consensus development conference published guidelines for the prevention and treatment of imported P. falciparum malaria. The impact of these guidelines has not been evaluated.

AIM

To investigate the impact of these guidelines on the prescription of anti-malarials, and to evaluate the incidence of acute drug events (ADEs) leading to discontinuation of treatment.

DESIGN

Cross-sectional survey.

METHODS

Members of the medical staff in 14 French infectious and tropical disease wards completed a standardized form for each patient treated for imported malaria in 2001. A propensity score matching technique was used to estimate the risk of ADEs leading to discontinuation of the regimen.

RESULTS

In the 474 patients studied, quinine was the first-line anti-malarial most often prescribed. Only 3% of patients received halofantrine. Mefloquine was associated with a RR of 4.9 (95%CI 3.2-7.4, p < 0.00001) risk of discontinuation of treatment due to ADEs.

DISCUSSION

The very limited use of halofantrine indicates that the main practice recommendations of the guidelines have been taken into account. Mefloquine was associated with a substantial risk of discontinuing the treatment because of ADEs. This is a serious limitation for the use of mefloquine in the treatment of out-patients with imported malaria.

Epidemiological, clinical and biological features of malaria among children in Niamey, Niger

Background

Malaria takes a heavy toll in Niger, one of the world's poorest countries. Previous evaluations conducted in the context of the strategy for the Integrated Management of Childhood Illness, showed that 84% of severe malaria cases and 64 % of ordinary cases are not correctly managed. The aim of this survey was to describe epidemiological, clinical and biological features of malaria among <5 year-old children in the paediatric department of the National Hospital of Niamey, Niger's main referral hospital.

Methods

The study was performed in 2003 during the rainy season from July 25^th to October 25^th. Microscopic diagnosis of malaria, complete blood cell counts and measurement of glycaemia were performed in compliance with the routine procedure of the laboratory. Epidemiological data was collected through interviews with mothers.

Results

256 children aged 3–60 months were included in the study. Anthropometrics and epidemiological data were typical of a very underprivileged population: 58% of the children were suffering from malnutrition and all were from poor families. Diagnosis of malaria was confirmed by microscopy in 52% of the cases. Clinical symptoms upon admission were non-specific, but there was a significant combination between a positive thick blood smear and neurological symptoms, and between a positive thick blood smear and splenomegaly. Thrombopaenia was also statistically more frequent among confirmed cases of malaria. The prevalence of severe malaria was 86%, including cases of severe anaemia among < 2 year-old children and neurological forms after 2 years of age. Overall mortality was 20% among confirmed cases and 21% among severe cases.

Conclusions

The study confirmed that malaria was a major burden for the National Hospital of Niamey. Children hospitalized for malaria had an underprivileged background. Two distinctive features were the prevalence of severe malaria and a high mortality rate. Medical and non-medical underlying factors which may explain such a situation are discussed.