• Last line of defence

      de Smet, M (2009-06-20)
    • Local Constraints to Access Appropriate Malaria Treatment in the Context of Parasite Resistance in Cambodia: a Qualitative Study

      Verschuere, J; Decroo, T; Lim, D; Kindermans, JM; Nguon, C; Huy, R; Alkourdi, Y; Peeters Grietens, K; Gryseels, C (BioMed Central, 2017-02-17)
      Despite emerging drug resistance in Cambodia, artemisinin-based combination therapy (ACT) is still the most efficacious therapy. ACT is available free of charge in the Cambodian public sector and at a subsidized rate in the private sector. However, un- and mistreated cases in combination with population movements may lead to the further spread of resistant parasites, stressing the importance of understanding how the perceived aetiology of malaria and associated health-seeking behaviour may delay access to appropriate treatment. A qualitative study explored these factors after an epidemiological survey confirmed parasite resistance in Preah Vihear province.
    • Long-lasting insecticide-treated net usage in eastern Sierra Leone - the success of free distribution.

      Gerstl, Sibylle; Dunkley, Sophie; Mukhtar, Ahmed; Maes, Peter; De Smet, Martin; Baker, Samuel; Maikere, Jacob; Médecins Sans Frontières-United Kingdom, London, UK. (2010-02-09)
      Summary Objective Médecins Sans Frontières (MSF) runs a malaria control project in Bo and Pujehun districts (population 158 000) that includes the mass distribution, routine delivery and demonstration of correct use of free, long-lasting insecticide-treated nets (LLINs). In 2006/2007, around 65 000 LLINs were distributed. The aim of this follow-up study was to measure LLIN usage and ownership in the project area. Methods Heads of 900 randomly selected households in 30 clusters were interviewed, using a standardized questionnaire, about household use of LLINs. The condition of any LLIN was physically assessed. Results Of the 900 households reported, 83.4% owning at least one LLIN. Of the 16.6% without an LLIN, 91.9% had not participated in the MSF mass distribution. In 94.1% of the households reporting LLINs, the nets were observed hanging correctly over the beds. Of the 1135 hanging LLINs, 75.2% had no holes or 10 or fewer finger-size holes. The most common source of LLINs was MSF (75.2%). Of the 4997 household members, 67.2% reported sleeping under an LLIN the night before the study, including 76.8% of children under 5 years and 73.0% of pregnant women. Conclusion Our results show that MSF achieved good usage with freely distributed LLINs. It is one of the few areas where results almost achieve the new targets set in 2005 by Roll Back Malaria to have at least 80% of pregnant women and children under 5 years using LLINs by 2010.
    • Low efficacy of the combination artesunate plus amodiaquine for uncomplicated falciparum malaria among children under 5 years in Kailahun, Sierra Leone.

      Grandesso, F; Hagerman, A; Kamara, S; Lam, E; Checchi, F; Balkan, S; Scollo, G; Durand, R; Guthmann, J P; Epicentre, Paris, France. (Wiley-Blackwell, 2006-07)
      OBJECTIVE: In 2004, Sierra Leone adopted artesunate plus amodiaquine as first-line antimalarial treatment. We evaluated the efficacy of this combination in Kailahun, where a previous study had shown 70.2% efficacy of amodiaquine in monotherapy. METHODS: Method and outcome classification of the study complied with WHO guidelines. Children 6-59 months with uncomplicated malaria were followed-up for 28 days. PCR genotyping was used to distinguish recrudescence from reinfection. Reinfections were reclassified as cured. RESULTS: Of 172 children who were referred to the study clinic, 126 satisfied inclusion criteria and were enrolled. No early treatment failures were reported. The day 14, efficacy was 98.2% (95% CI: 93.8-99.8). Of 65 recurrent parasitaemias analysed by PCR, 17 were recrudescences. The PCR-adjusted day 28 efficacy was 84.5% (95% CI: 76.4-90.7). All true failures occurred in the last 8 days of follow-up. Of 110 children who completed the 28-day follow-up, 54 (49.1%) experienced a novel infection. CONCLUSION: The efficacy of this combination was disappointing. The high reinfection rate suggested little prophylactic effect. In Kailahun a more efficacious combination might be necessary in the future. The efficacy of AS + AQ needs to be monitored in Kailahun and in the other regions of Sierra Leone.
    • Low referral completion of rapid diagnostic test-negative patients in community-based treatment of malaria in Sierra Leone.

      Thomson, Anna; Khogali, Mohammed; de Smet, Martin; Reid, Tony; Mukhtar, Ahmed; Peterson, Stefan; von Schreeb, Johan; Division of Global Health, Karolinska Institutet, Stockholm, Sweden. anna.thomson@stockholm.msf.org. (2011-05)
      ABSTRACT:
    • Malaria in an Internally Displaced Persons Camp in the Democratic Republic of the Congo

      Brooks, H; Jean Paul, M; Claude, K; Houston, S; Hawkes, M (Oxford University Press, 2017-08-01)
    • Malaria in camps for internally-displaced persons in Uganda: evaluation of an insecticide-treated bednet distribution programme.

      Spencer, S; Grant, A D; Piola, P; Tukpo, K; Okia, M; Garcia, M; Salignon, P; Genevier, C; Kiguli, J; Guthmann, J P; et al. (ElsevierWiley-Blackwell, 2004-12)
      Malaria is a key health problem among displaced populations in malaria-endemic areas. Mass distribution of insecticide-treated bednets (ITN) to prevent malaria is often carried out in complex emergencies, but there are few data on the outcome or operational effectiveness of such programmes. In June 2001, Medecins Sans Frontieres completed a mass distribution of ITNs (Permanet) to internally displaced persons in Bundibugyo, southwest Uganda, distributing one to four nets per household, and aiming to provide coverage for all residents. In July 2002, we did a cross-sectional survey using three-stage cluster sampling to evaluate the programme. A total of 1245 individuals from 835 households were interviewed. An ITN was present in 75.6% (95% CI 72.7-78.5) of the households, but only 56.5% (95% CI 52.3-60.4) of individuals were sleeping under an ITN, and nets were often damaged. The prevalence of malarial parasitaemia was 11.2% (95% CI 9.4-13.0), and was significantly lower in ITN users compared to non-users (9.2% vs. 13.8%, relative risk [RR] 0.63, 95% CI 0.46-0.87); ITNs with severe damage remained effective (RR for severely damaged net 0.58, 95% CI 0.35-0.98). There was no significant difference in haemoglobin concentration between ITN users and non-users.
    • Malaria in pregnancy: a call for a safe, efficient, and patient-centred approach to first-trimester treatment.

      Rao, VB; Jensen, TO; Jimenez, BC; Robays, J; Lasry, E; Sterk, E; de Smet, M (Elsevier, 2018-06-06)
    • Malaria in the Nuba Mountains of Sudan: baseline genotypic resistance and efficacy of the artesunate plus sulfadoxine-pyrimethamine and artesunate plus amodiaquine combinations.

      Hamour, S; Melaku, Y; Keus, K; Wambugu, J; Atkin, S; Montgomery, J; Ford, N; Hook, C; Checchi, F; Médecins Sans Frontières, Plantage Middenlaan 14, 1018 DD Amsterdam, The Netherlands. (Elsevier, 2005-07)
      Both northern and southern Sudan are deploying artemisinin-based combinations against uncomplicated Plasmodium falciparum malaria (artesunate+sulfadoxine-pyrimethamine [AS+SP] in the north, artesunate+amodiaquine [AS+AQ] in the south). In 2003, we tested the efficacy of 3 day AS+SP and AS+AQ regimens in vivo in the isolated, seasonally endemic Nuba Mountains region (the first study of AS combinations in southern Sudan). We also analysed pre-treatment blood samples for mutations at the P. falciparum chloroquine transporter (Pfcrt) gene (associated with CQ resistance), and at the dihydrofolate reductase (Dhfr) gene (associated with pyrimethamine resistance). Among 161 randomized children under 5 years, PCR-corrected cure rates after 28 days were 91.2% (52/57, 95% CI 80.7-97.1) for AS+SP and 92.7% (51/55, 95% CI 82.4-98.0) for AS+AQ, with equally rapid parasite and fever clearance. The Pfcrt K76T mutation occurred in 90.0% (144/160) of infections, suggesting CQ would work poorly in this region. Overall, 82.5% (132/160) carried mutations at Dhfr (N51I, C59R or S108N, but not I164L), but triple mutants (more predictive of in vivo SP failure) were rare (3.1%). CQ use should be rapidly discontinued in this region. SP resistance may propagate rapidly, and AS+AQ is likely to be a better long-term option, provided AQ use is limited to the combination.
    • Malaria is an uncommon cause of adult sepsis in south-western Uganda

      Auma, Mary A; Siedner, Mark J; Nyehangane, Dan; Nalusaji, Aisha; Nakaye, Martha; Mwanga-Amumpaire, Juliet; Muhindo, Rose; Wilson, L Anthony; Boum, Yap; Moore, Christopher C; et al. (BioMed Central, 2013-05-01)
      Malaria is often considered a cause of adult sepsis in malaria endemic areas. However, diagnostic limitations can make distinction between malaria and other infections challenging. Therefore, the objective of this study was to determine the relative contribution of malaria to adult sepsis in south-western Uganda.
    • Malaria PCR Detection in Cambodian Low-Transmission Settings: Dried Blood Spots Versus Venous Blood Samples

      Canier, Lydie; Khim, Nimol; Kim, Saorin; Eam, Rotha; Khean, Chanra; Loch, Kaknika; Ken, Malen; Pannus, Pieter; Bosman, Philippe; Stassijns, Jorgen; et al. (American Society of Tropical Medicine and Hygiene, 2015-01-05)
      In the context of malaria elimination, novel strategies for detecting very low malaria parasite densities in asymptomatic individuals are needed. One of the major limitations of the malaria parasite detection methods is the volume of blood samples being analyzed. The objective of the study was to compare the diagnostic accuracy of a malaria polymerase chain reaction assay, from dried blood spots (DBS, 5 μL) and different volumes of venous blood (50 μL, 200 μL, and 1 mL). The limit of detection of the polymerase chain reaction assay, using calibrated Plasmodium falciparum blood dilutions, showed that venous blood samples (50 μL, 200 μL, 1 mL) combined with Qiagen extraction methods gave a similar threshold of 100 parasites/mL, ∼100-fold lower than 5 μL DBS/Instagene method. On a set of 521 field samples, collected in two different transmission areas in northern Cambodia, no significant difference in the proportion of parasite carriers, regardless of the methods used was found. The 5 μL DBS method missed 27% of the samples detected by the 1 mL venous blood method, but most of the missed parasites carriers were infected by Plasmodium vivax (84%). The remaining missed P. falciparum parasite carriers (N = 3) were only detected in high-transmission areas.
    • Malaria surveillance among the displaced Karen population in Thailand April 1984 to February 1989, Mae Sot, Thailand.

      Decludt, B; Pecoul, B; Biberson, P; Lang, R; Imivithaya, S; Medecins sans Frontieres, Paris, France. (1991-12)
      Right from the arrival of the displaced Karen people in Thailand, Médecins sans Frontières (MSF) identified malaria as the top priority problem. A program of patient care based on the coupled laboratory/dispensary was set up in April 1984. Immediately a system of surveillance of morbidity and mortality from malaria was set up. This study consisted of analysing data gathered over a period of five years. During this time, the displaced population increased from 9,000 to 20,000. Analysis of the trends shows a hyperendemic situation with an annual incidence rate of 1,067 per thousand in 1984. This figure was 600 per thousand in 1988. 1,500 blood smears were checked each month and the positive predictive value of clinical suspicion was 45% on average. Plasmodium falciparum represented 80% of infections. The malaria case fatality ratio over the course of the last two years of surveillance was 0.3%. Five years observation show that the fight against malaria in this region can be based on the development of curative services and laboratories.
    • Malaria, malnutrition and MSF. Médecins Sans Frontières.

      Evans, D; Médecins Sans Frontières, Glebe, NSW. office@sydney.msf.org (Medical Society of Australia, 2008-02-21)
      This is a personal account of my brief time in Burundi as a volunteer doctor with Médecins Sans Frontières (MSF) at the beginning of 2001. Burundi is a small nation in central Africa (bounded by the Democratic Republic of Congo, Rwanda and Tanzania) which has suffered from problems between the Hutu and Tutsi "ethnic groups", similar to those for which Rwanda is better known. Unlike Rwanda, the war between government troops and rebel forces continues in Burundi. MSF has been in Burundi since 1992, providing basic healthcare, nutrition programs, surgical services and epidemiological intervention. In late 2000, a malaria epidemic began in Burundi's highland regions where transmission is normally low, and thus the population largely not immune. Malnutrition rates also increased and MSF rapidly expanded its usual program in an attempt to control these new health problems.
    • Malaria: current status of control, diagnosis, treatment, and a proposed agenda for research and development.

      Guerin, P J; Olliaro, P; Nosten, F; Druilhe, P; Laxminarayan, R; Binka, F; Kilama, W L; Ford, N; White, N J; Norwegian Institute of Public Health, Norway. philippe.guerin@fhi.no (2002-09)
      Rolling back malaria is possible. Tools are available but they are not used. Several countries deploy, as their national malaria control treatment policy, drugs that are no longer effective. New and innovative methods of vector control, diagnosis, and treatment should be developed, and work towards development of new drugs and a vaccine should receive much greater support. But the pressing need, in the face of increasing global mortality and general lack of progress in malaria control, is research into the best methods of deploying and using existing approaches, particularly insecticide-treated mosquito nets, rapid methods of diagnosis, and artemisinin-based combination treatments. Evidence on these approaches should provide national governments and international donors with the cost-benefit information that would justify much-needed increases in global support for appropriate and effective malaria control.
    • Markers of sulfadoxine-pyrimethamine resistance in Eastern Democratic Republic of Congo; implications for malaria chemoprevention.

      van Lenthe, M; van der Meulen, R; Lassovski, M; Ouabo, A; Bakula, E; Badio, C; Cibenda, D; Okell, L; Piriou, E; Grignard, L; et al. (BioMed Central, 2019-12-18)
      BACKGROUND: Sulfadoxine-pyrimethamine (SP) is a cornerstone of malaria chemoprophylaxis and is considered for programmes in the Democratic Republic of Congo (DRC). However, SP efficacy is threatened by drug resistance, that is conferred by mutations in the dhfr and dhps genes. The World Health Organization has specified that intermittent preventive treatment for infants (IPTi) with SP should be implemented only if the prevalence of the dhps K540E mutation is under 50%. There are limited current data on the prevalence of resistance-conferring mutations available from Eastern DRC. The current study aimed to address this knowledge gap. METHODS: Dried blood-spot samples were collected from clinically suspected malaria patients [outpatient department (OPD)] and pregnant women attending antenatal care (ANC) in four sites in North and South Kivu, DRC. Quantitative PCR (qPCR) was performed on samples from individuals with positive and with negative rapid diagnostic test (RDT) results. Dhps K450E and A581G and dhfr I164L were assessed by nested PCR followed by allele-specific primer extension and detection by multiplex bead-based assays. RESULTS: Across populations, Plasmodium falciparum parasite prevalence was 47.9% (1160/2421) by RDT and 71.7 (1763/2421) by qPCR. Median parasite density measured by qPCR in RDT-negative qPCR-positive samples was very low with a median of 2.3 parasites/µL (IQR 0.5-25.2). Resistance genotyping was successfully performed in RDT-positive samples and RDT-negative/qPCR-positive samples with success rates of 86.2% (937/1086) and 55.5% (361/651), respectively. The presence of dhps K540E was high across sites (50.3-87.9%), with strong evidence for differences between sites (p < 0.001). Dhps A581G mutants were less prevalent (12.7-47.2%). The dhfr I164L mutation was found in one sample. CONCLUSIONS: The prevalence of the SP resistance marker dhps K540E exceeds 50% in all four study sites in North and South Kivu, DRC. K540E mutations regularly co-occurred with mutations in dhps A581G but not with the dhfr I164L mutation. The current results do not support implementation of IPTi with SP in the study area.
    • Markers of sulfadoxine–pyrimethamine resistance in Eastern Democratic Republic of Congo; implications for malaria chemoprevention

      van Lenthe, M; van der Meulen, R; Okell, L; Piriou, E; Lassovski, M; Bakula, E; Badio, C; Roper, C; Bousema, T; Ouabo, A; et al. (Springer Science and Business Media LLC, 2019-12-18)
      Background Sulfadoxine–pyrimethamine (SP) is a cornerstone of malaria chemoprophylaxis and is considered for programmes in the Democratic Republic of Congo (DRC). However, SP efficacy is threatened by drug resistance, that is conferred by mutations in the dhfr and dhps genes. The World Health Organization has specified that intermittent preventive treatment for infants (IPTi) with SP should be implemented only if the prevalence of the dhps K540E mutation is under 50%. There are limited current data on the prevalence of resistance-conferring mutations available from Eastern DRC. The current study aimed to address this knowledge gap. Methods Dried blood-spot samples were collected from clinically suspected malaria patients [outpatient department (OPD)] and pregnant women attending antenatal care (ANC) in four sites in North and South Kivu, DRC. Quantitative PCR (qPCR) was performed on samples from individuals with positive and with negative rapid diagnostic test (RDT) results. Dhps K450E and A581G and dhfr I164L were assessed by nested PCR followed by allele-specific primer extension and detection by multiplex bead-based assays. Results Across populations, Plasmodium falciparum parasite prevalence was 47.9% (1160/2421) by RDT and 71.7 (1763/2421) by qPCR. Median parasite density measured by qPCR in RDT-negative qPCR-positive samples was very low with a median of 2.3 parasites/µL (IQR 0.5–25.2). Resistance genotyping was successfully performed in RDT-positive samples and RDT-negative/qPCR-positive samples with success rates of 86.2% (937/1086) and 55.5% (361/651), respectively. The presence of dhps K540E was high across sites (50.3–87.9%), with strong evidence for differences between sites (p < 0.001). Dhps A581G mutants were less prevalent (12.7–47.2%). The dhfr I164L mutation was found in one sample. Conclusions The prevalence of the SP resistance marker dhps K540E exceeds 50% in all four study sites in North and South Kivu, DRC. K540E mutations regularly co-occurred with mutations in dhps A581G but not with the dhfr I164L mutation. The current results do not support implementation of IPTi with SP in the study area.
    • Methodological Issues in the Assessment of Antimalarial Drug Treatment: Analysis of 13 Studies in Eight African Countries from 2001 to 2004.

      Guthmann, J P; Pinoges, L; Checchi, F; Cousens, S; Balkan, S; Van Herp, M; Legros, D; Olliaro, P; Epicentre, 8 rue Saint Sabin, 75011 Paris, France. jguthmann@epicentre.msf.org (Published by American Society for Microbiology, 2006-11)
      The objectives of these analyses were to assess the feasibility of the latest WHO recommendations (28-day follow-up with PCR genotyping) for the assessment of antimalarial drug efficacy in vivo and to examine how different statistical approaches affect results. We used individual-patient data from 13 studies of uncomplicated pediatric falciparum malaria conducted in sub-Saharan Africa, using chloroquine (CQ), sulfadoxine/pyrimethamine (SP), or amodiaquine (AQ). We assessed the use effectiveness and test performance of PCR genotyping in distinguishing recurrent infections. In analyzing data, we compared (i) the risk of failure on target days (days 14 and 28) by using Kaplan-Meier and per-protocol evaluable patient analyses, (ii) PCR-corrected results allowing (method 1) or excluding (method 2) new infections, (iii) and day 14 versus day 28 results. Of the 2,576 patients treated, 2,287 (89%) were evaluable on day 28. Of the 695 recurrences occurring post-day 14, 650 could be processed and 584 were resolved (PCR use effectiveness, 84%; test performance, 90%). The risks of failure on day 28 with Kaplan-Meier and evaluable-patient analyses tended to be generally close (except in smaller studies) because the numbers of dropouts were minimal, but attrition rates on day 28 were higher with the latter method. Method 2 yielded higher risks of failure than method 1. Extending observation to 28 days produced higher estimated risks of failure for SP and AQ but not for CQ (high failure rates by day 14). Results support the implementation of the current WHO protocol and favor analyzing PCR-corrected outcomes by Kaplan-Meier analysis (which allows for dropouts) and retaining new infections (which minimizes losses).
    • Modeling of EBV Infection and Antibody Responses in Kenyan Infants with Different Levels of Malaria Exposure Shows Maternal Antibody Decay is a Major Determinant of Early EBV Infection

      Reynaldi, A; Schlub, TE; Piriou, E; Ogolla, S; Sumba, OP; Moormann, AM; Rochford, R; Davenport, MP (Oxford University Press, 2016-08-28)
      The combination of Epstein-Barr virus (EBV) infection and high malaria exposure are risk factors for endemic Burkitt lymphoma, and evidence suggests that infants in regions of high malaria exposure have earlier EBV infection and increased EBV reactivation. Here we analysed the longitudinal antibody response to EBV in Kenyan infants with different levels of malaria exposure. We found that high malaria exposure was associated with a faster decline of maternally-derived IgG antibody to both the EBV viral capsid antigen (VCA) and Epstein-Barr virus nuclear antigen (EBNA1), followed by a more rapid rise in antibody response to EBV antigens in children from the high malaria region. In addition, we observed the long-term persistence of anti-VCA IgM responses in children from the malaria high region. More rapid decay of maternal antibodies was a major predictor of EBV infection outcome, as decay predicted time-to EBV DNA detection, independent of high and low malaria exposure.
    • Molecular genotyping in a malaria treatment trial in Uganda - unexpected high rate of new infections within 2 weeks after treatment.

      Mugittu, K; Priotto, G; Guthmann, J P; Kiguli, J; Adjuik, M; Snounou, G; Beck, H P; Mshinda, H; Olliaro, P; Taylor, W R J; et al. (2007-02)
      Polymerase chain reaction (PCR) genotyping of malaria parasites in drug efficacy trials helps differentiate reinfections from recrudescences. A combination therapy trial of one (n = 115) or three (n = 117) days artesunate (1AS, 3AS 4 mg/kg/day) plus sulphadoxine-pyrimethamine (SP) vs. SP alone (n = 153) was conducted in Mbarara, a mesoendemic area of western Uganda. All paired recurrent Plasmodium falciparum parasitaemias on days 7, 14, 21 and 28 post-treatment were genotyped by PCR amplification and analysis of glutamate-rich protein (glurp) and merozoite surface proteins (msp) 1 and 2 genes to distinguish recrudescent from new infections. A total of 156 (1AS = 61, 3AS = 35, SP alone = 60) of 199 paired recurrent samples were successfully analysed and were resolved as 79 recrudescences (1AS = 32, 3AS = 8, SP = 39) and 77 as new infections (1AS = 29, 3AS = 27, SP = 21). The ratios of proportions of new to recrudescent infections were 0.2, 0.9, 1.4 and 1.9 on days 7, 14, 21 and 28, respectively (P < 0.001, chi(2) test for linear trend). Unexpected high new infection rates were observed early in follow-up on days 7 [5/26 (19.2%)] and 14 [24/51 (47.1%)]. These results impact significantly on resistance monitoring and point to the value of genotyping all recurrent infections in antimalarial trials.
    • Molecular markers of resistance to amodiaquine plus sulfadoxine-pyrimethamine in an area with seasonal malaria chemoprevention in south central Niger

      Grais, RF; Laminou, IM; Woi-Messe, L; Makarimi, R; Bouriema, SH; Langendorf, C; Amambua-Ngwa, A; D'Alessandro, U; Guérin, PJ; Fandeur, T; et al. (BioMed Central, 2018-02-27)
      In Niger, malaria transmission is markedly seasonal with most of the disease burden occurring in children during the rainy season. Seasonal malaria chemoprevention (SMC) with amodiaquine plus sulfadoxine-pyrimethamine (AQ + SP) is recommended in the country to be administered monthly just before and during the rainy season. Moreover, clinical decisions on use of SP for intermittent preventive treatment in pregnancy (IPTp) now depend upon the validated molecular markers for SP resistance in Plasmodium falciparum observed in the local parasite population. However, little is known about molecular markers of resistance for either SP or AQ in the south of Niger. To address this question, clinical samples which met clinical and biological criteria, were collected in Gabi, Madarounfa district, Maradi region, Niger in 2011-2012 (before SMC implementation). Molecular markers of resistance to pyrimethamine (pfdhfr), sulfadoxine (pfdhps) and amodiaquine (pfmdr1) were assessed by DNA sequencing.