Efficacy of sulfadoxine-pyrimethamine for the treatment of uncomplicated falciparum malaria in Ethiopia

Artemether-lumefantrin treatment adherence among uncomplicated plasmodium falciparum malaria patients, visiting public health facilities in AsgedeTsimbla district, Tigray, Ethiopia: a cross-sectional study

Background

Ethiopia has set a goal to eliminate malaria by 2030; Artemether–lumefantrine (AL) is put as one of the cornerstone strategies for uncomplicated plasmodium falciparum malaria treatment. However, only focusing on prescribing of the treatment without assessing patients’ adherence could lead to the resistance of the drug. In Ethiopia, there is limited evidence about patients’ adherence to AL and its influencing factors. Therefore, this study aimed at addressing this information gap.

Methods

A health facility based cross-sectional study was employed. Participants were selected using simple random sampling technique from registration books of the public health facilities in AsgedeTsimbla. Data were collected from March 24th to April 30th, 2018. We interviewed participants using a pre-tested structured questionnaire, and the blister pack was also inspected at their homes on day 4. Data were entered into Epi-Info and analyzed using SPSS 21. Odds ratios with 95% Confidence Intervals were estimated and the level of significance was declared at p-value ≤ 0.05.

Results

A total of 384 study participants were interviewed with a response rate of 95.5%. The overall AL adherence was 53.6% (95% CI 48.4–58.3%). Children aged < 5 years [AOR: 0.4, 95% CI (0.2–0.8)], and being treated in health post [AOR: 0.3, 95% CI (0.1–0.5)] were more likely to show AL adherence whereas illiteracy [AOR: 9.4, 95% CI (4.2–21.3)], didn’t know the consequence of discontinued AL [AOR: 4.0, 95% CI (2.1–7.6)], had concomitant drugs [AOR: 2.5, 95% CI (1.4–4.5)], and stopped/saved drug when improved before tablet got finished [AOR: 3.2, 95% CI (1.7–5.9)] were factors less likely to be associated with AL adherence.

Conclusion

AL adherence was low. Children aged < 5 years, and being treated in health post were determinants of AL adherence whereas illiteracy, didn’t know the consequence of discontinued the drug, had concomitant drugs, and stopped/saved drug when improved before tablet got finished were factors that hindered the AL adherence. Stakeholders should emphasize designing appropriate strategies including educational interventions to increase the AL adherence and prevent drug resistance. Further research should be conducted to evaluate AL resistance.

Serological evidence for a decline in malaria transmission following major scale-up of control efforts in a setting selected for Plasmodium vivax and Plasmodium falciparum malaria elimination in Babile district, Oromia, Ethiopia

BACKGROUND

Following successful malaria control during the last decade, Ethiopia instituted a stepwise malaria elimination strategy in selected low-transmission areas.

METHODS

Cross-sectional surveys were conducted in Babile district, Oromia, Ethiopia from July to November 2017 to evaluate malaria infection status using microscopy and nested polymerase chain reaction (nPCR) and serological markers of exposure targeting Plasmodium falciparum and Plasmodium vivax apical membrane antigen-1 (AMA-1).

RESULTS

Parasite prevalence was 1.2% (14/1135) and 5.1% (58/1143) for P. falciparum and 0.4% (5/1135) and 3.6% (41/1143) for P. vivax by microscopy and nPCR, respectively. Antibody prevalence was associated with current infection by nPCR for both P. falciparum (p<0.001) and P. vivax (p=0.014) and showed an age-dependent increase (p<0.001, for both species). Seroconversion curves indicated a decline in malaria exposure 15 y prior to sampling for P. falciparum and 11.5 y prior to sampling for P. vivax, broadly following malaria incidence data from district health offices, with higher antibody titres in adults than children for both species.

CONCLUSIONS

Malaria transmission declined substantially in the region with continuing heterogeneous but measurable local transmission, arguing in favour of continued and tailored control efforts to accelerate the progress towards elimination efforts.

Prevalence of Plasmodium falciparum Pfcrt and Pfmdr1 alleles in settings with different levels of Plasmodium vivax co-endemicity in Ethiopia

Plasmodium falciparum and P. vivax co-exist at different endemicity levels across Ethiopia. For over two decades Artemether-Lumefantrine (AL) is the first line treatment for uncomplicated P. falciparum, while chloroquine (CQ) is still used to treat P. vivax. It is currently unclear whether a shift from CQ to AL for P. falciparum treatment has implications for AL efficacy and results in a reversal of mutations in genes associated to CQ resistance, given the high co-endemicity of the two species and the continued availability of CQ for the treatment of P. vivax. This study thus assessed the prevalence of Pfcrt-K76T and Pfmdr1-N86Y point mutations in P. falciparum. 18S RNA gene based nested PCR confirmed P. falciparum samples (N = 183) collected through community and health facility targeted cross-sectional surveys from settings with varying P. vivax and P. falciparum endemicity were used. The proportion of Plasmodium infections that were P. vivax was 62.2% in Adama, 41.4% in Babile, 30.0% in Benishangul-Gumuz to 6.9% in Gambella. The Pfcrt-76T mutant haplotype was observed more from samples with higher endemicity of P. vivax as being 98.4% (61/62), 100% (31/31), 65.2% (15/23) and 41.5% (22/53) in samples from Adama, Babile, Benishangul-Gumuz and Gambella, respectively. However, a relatively higher proportion of Pfmdr1-N86 allele (77.3–100%) were maintained in all sites. The observed high level of the mutant Pfcrt-76T allele in P. vivax co-endemic sites might require that utilization of CQ needs to be re-evaluated in settings co-endemic for the two species. A country-wide assessment is recommended to clarify the implication of the observed level of variation in drug resistance markers on the efficacy of AL-based treatment against uncomplicated P. falciparum malaria.

Malaria epidemiology and interventions in Ethiopia from 2001 to 2016

BACKGROUND

Ethiopia is one of the African countries where Plasmodium falciparum and P. vivax co-exist. Monitoring and evaluation of current malaria transmission status is an important component of malaria control as it is a measure of the success of ongoing interventions and guides the planning of future control and elimination efforts.

MAIN TEXT

We evaluated changes in malaria control policy in Ethiopia, and reviewed dynamics of country-wide confirmed and clinical malaria cases by Plasmodium species and reported deaths for all ages and less than five years from 2001 to 2016. Districts level annual parasite incidence was analysed to characterize the malaria transmission stratification as implemented by the Ministry of Health. We found that Ethiopia has experienced major changes from 2003 to 2005 and subsequent adjustment in malaria diagnosis, treatment and vector control policy. Malaria interventions have been intensified represented by the increased insecticide treated net (ITN) and indoor residual spraying (IRS) coverage, improved health services and improved malaria diagnosis. However, countrywide ITN and IRS coverages were low, with 64% ITN coverage in 2016 and IRS coverage of 92.5% in 2016 and only implemented in epidemic-prone areas of > 2500 m elevation. Clinical malaria incidence rate dropped from an average of 43.1 cases per 1000 population annually between 2001 and 2010 to 29.0 cases per 1000 population annually between 2011 and 2016. Malaria deaths decreased from 2.1 deaths per 100 000 people annually between 2001 and 2010 to 1.1 deaths per 100 000 people annually between 2011 to 2016. There was shrinkage in the malaria transmission map and high transmission is limited mainly to the western international border area. Proportion of P. falciparum malaria remained nearly unchanged from 2000 to 2016 indicating further efforts are needed to suppress transmission.

CONCLUSIONS

Malaria morbidity and mortality have been significantly reduced in Ethiopia since 2001, however, malaria case incidence is still high, and there were major gaps between ITN ownership and compliance in malarious areas. Additional efforts are needed to target the high transmission area of western Ethiopia to sustain the achievements made to date.

Therapeutic efficacy of artemether-lumefantrine in the treatment of uncomplicated Plasmodium falciparum malaria in Ethiopia: a systematic review and meta-analysis

Background

As Ethiopia is one of the sub-Saharan countries with a great burden of malaria the effectiveness of first line anti-malarial drugs is the major concern. The aim of this study was to synthesize the available evidence on the efficacy of artemether-lumefantrine in the treatment of uncomplicated Plasmodium falciparum malaria in Ethiopia. This was done by performing a meta-analysis of recent studies conducted in the country on this topic.

Methods

Studies published between January 2010 and January 2017 that reported on the efficacy of artemether-lumefantrine in the treatment of P. falciparum malaria in Ethiopian patients were searched for using the PubMed and Google Scholar databases. Ten prospective single-arm cohort studies that followed patients for 28–42 days were included in this analysis. All of the included studies were deemed to be of high quality.

Results

Ten studies involving 1179 patients that were eligible for meta-analysis were identified. At recruitment, the average parasite count per patient was 1 2981/μl of blood. On the third day of treatment, 96.7% and 98.5% of the study subjects become fever-free and parasite-free, respectively. Based on the per protocol analysis, the cure rate after use of artemether-lumefantrine was 98.2% (polymerase chain reaction corrected) and 97.01% (polymerase chain reaction uncorrected) after 28 days of follow-up. The reinfection rate within 28 days was 1.1% and the recrudescence rate was 1.9%.

Conclusions

This review found that the cure rate for uncomplicated P. falciparum malaria using artemether-lumefantrine in Ethiopia is still high enough to recommend the drug as a first-line agent. There should be careful periodic monitoring of the efficacy of this drug, as treatment failure may occur due to resistance, sub-therapeutic levels that may occur due to non-adherence, or inadequate absorption.

Electronic supplementary material

The online version of this article (10.1186/s40249-017-0372-5) contains supplementary material, which is available to authorized users.

Anti-malarial treatment outcomes in Ethiopia: a systematic review and meta-analysis

BACKGROUND

Ethiopia is among countries with a high malaria burden. There are several studies that assessed the efficacy of anti-malarial agents in the country and this systematic review and meta-analysis was performed to obtain stronger evidence on treatment outcomes of malaria from the existing literature in Ethiopia.

METHODS

A systematic literature search using the preferred reporting items for systematic review and meta-analysis (PRISMA) statement was conducted on studies from Pubmed, Google Scholar, and ScienceDirect databases to identify published and unpublished literature. Comprehensive meta-analysis software was used to perform all meta-analyses. The Cochrane Q and the I 2 were used to evaluate heterogeneity of studies. Random effects model was used to combine studies showing heterogeneity of Cochrane Q p < 0.10 and I 2  > 50.

RESULTS

Twenty-one studies were included in the final analysis with a total number of 3123 study participants. Treatment outcomes were assessed clinically and parasitologically using World Health Organization guidelines. Adequate clinical and parasitological response was used to assess treatment success at the 28th day. Overall, a significant high treatment success of 92.9% (95% CI 89.1-96.6), p < 0.001, I 2  = 98.39% was noticed. However, treatment success was higher in falciparum malaria patients treated with artemether-lumefantrine than chloroquine for Plasmodium vivax patients [98.1% (97.0-99.2), p < 0.001, I 2  = 72.55 vs 94.7% (92.6-96.2), p < 0.001, I 2  = 53.62%]. Seven studies reported the adverse drug reactions to anti-malarial treatment; of 822 participants, 344 of them were exposed to adverse drug reactions with a pooled event rate of 39.8% (14.1-65.5), p = 0.002.

CONCLUSIONS

On the basis of this review, anti-malarial treatment success was high (92.9%) and standard regimens showed good efficacy against Plasmodium falciparum (98.1%) and P. vivax (94.7%) infections in Ethiopia, but associated with high rates of adverse drug reactions (ADRs). However, these ADRs were not serious enough to discontinue anti-malarial treatment. The results of this study suggest that the current anti-malarial medications are effective and safe; however, greater priority should be placed on the discovery of new anti-malarial drugs to achieve successful outcomes as resistance seems inevitable since cases of anti-malarial drug resistance have been reported from other areas of the world.

High efficacy of artemether-lumefantrine and declining efficacy of artesunate + sulfadoxine-pyrimethamine against Plasmodium falciparum in Sudan (2010-2015): evidence from in vivo and molecular marker studies

Background

The present paper reports on studies that evaluated artesunate + sulfadoxine-pyrimethamine (AS + SP) which is the first-line drug and artemether-lumefantrine (AL) which is a second-line drug against uncomplicated falciparum malaria in Sudan. This evaluation was performed in twenty studies covering six sentinel sites during five successive annual malaria transmission seasons from 2010 to 2015.

Methods

The standard World Health Organization protocol was used for a follow-up period of 28 days. The frequency distribution of molecular markers for antifolate resistance in dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes was studied in pre-treatment samples in four sites in 2011.

Results

In the nine studies of AL conducted at five sites (n = 595), high PCR-corrected cure rates were found, ranging from 96.8 to 100 %. Among the eleven studies of AS + SP (n = 1013), a decline in the PCR-corrected cure rates was observed in Gedaref in Eastern Sudan: 91.0 % in the 2011–12 season and 86.5 % in the 2014–15 season. In the remaining sites, the AS + SP cure rates ranged between 95.6 and 100 %. The rate of clearance of microscopic gametocytaemia after treatment was not significantly different with AL or AS + SP on days 7, 14, 21 and 28 of follow-up. A total of 371 pre-treatment samples were analysed for molecular markers of SP resistance. The temporal changes and geographical differences in the frequency distribution of SP-resistance genotypes showed evidence of regional differentiation and selection of resistant strains.

Conclusion

The findings of this study call for a need to review the Sudan malaria treatment policy. Epidemiological factors could play a major role in the emergence of drug-resistant malaria in eastern Sudan.

Australian New Zealand Clinical Trials Registry

Trial registration numbers 2011–2012: ACTRN12611001253998, 2013–2015: ACTRN12613000945729

Combining long-lasting insecticidal nets and indoor residual spraying for malaria prevention in Ethiopia: study protocol for a cluster randomized controlled trial

BACKGROUND

Long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the main malaria prevention interventions in Ethiopia. There is conflicting evidence that the combined application of both interventions is better than either LLINs or IRS used alone. This trial aims to investigate whether the combination of LLINs (PermaNet 2.0, Vestergaard Frandsen, Lausanne, Switzerland) with IRS using propoxur will enhance the protective benefits and cost-effectiveness of the interventions against malaria and its effect on mosquito behavior, as compared to each intervention alone.

METHODS/DESIGN

This 2 x 2 factorial cluster randomized controlled trial is being carried out in the Adami Tullu district in south-central Ethiopia for about 116 weeks from September 2014 to December 2016. The trial is based on four arms: LLINs + IRS, LLINs alone, IRS alone and control. Villages (or clusters) will be the unit of randomization. The sample size includes 44 clusters per arm, with each cluster comprised of approximately 35 households (about 175 people). Prior to intervention, all households in the LLINs + IRS and LLINs alone arms will be provided with LLINs free of charge. Households in the LLINs + IRS and IRS alone arms will be sprayed with carbamate propoxur once a year just before the main malaria transmission season throughout the investigation. The primary outcome of this trial will be a malaria incidence based on the results of the rapid diagnostic tests in patients with a fever or history of fever attending health posts by passive case detection. Community-based surveys will be conducted each year to assess anemia among children 5-59 months old. In addition, community-based malaria prevalence surveys will be conducted each year on a representative sample of households during the main transmission season. The cost-effectiveness of the interventions and entomological studies will be simultaneously conducted. Analysis will be based on an intention-to-treat principle.

DISCUSSION

This trial aims to provide evidence on the combined use of LLINs and IRS for malaria prevention by answering the following research questions: Can the combined use of LLINs and IRS significantly reduce the incidence of malaria compared with the use of either LLINs or IRS alone? And is the reduced incidence justifiable compared to the added costs? Will the combined use of LLINs and IRS reduce vector density, infection, longevity and the entomological inoculation rate? These data are crucial in order to maximize the impact of vector control interventions on the morbidity and mortality of malaria.

TRIAL REGISTRATION

PACTR201411000882128 (8 September 2014).

Declining trend of Plasmodium falciparum dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) mutant alleles after the withdrawal of Sulfadoxine-Pyrimethamine in North Western Ethiopia

Antimalarial drug resistance is one of the major challenges in global efforts of malaria control and elimination. In 1998, chloroquine was abandoned and replaced with sulfadoxine/pyrimethamine, which in turn was replaced with artemether/lumefantrine for the treatment of uncomplicated falciparum malaria in 2004. Sulfadoxine/pyrimethamine resistance is associated with mutations in dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes. The prevalence of mutation in Pfdhfr and Pfdhps genes were evaluated and compared for a total of 159 isolates collected in two different time points, 2005 and 2007/08, from Pawe hospital, in North Western Ethiopia. The frequency of triple Pfdhfr mutation decreased significantly from 50.8% (32/63) to 15.9% (10/63) (P<0.001), while Pfdhps double mutation remained high and changed only marginally from 69.2% (45/65) to 55.4% (40/65) (P = 0.08). The combined Pfdhfr/Pfdhps quintuple mutation, which is strongly associated with sulfadoxine/pyrimethamine resistance, was significantly decreased from 40.7% (24/59) to 13.6% (8/59) (P<0.0001). On the whole, significant decline in mutant alleles and re-emergence of wild type alleles were observed. The change in the frequency is explained by the reduction of residual drug-resistant parasites caused by the strong drug pressure imposed when sulfadoxine/pyrimethamine was the first-line drug, followed by lower fitness of these resistant parasites in the absence of drug pressure. Despite the decrease in the frequency of mutant alleles, higher percentages of mutation remain prevalent in the study area in 2007/08 in both Pfdhfr and Pfdhps genes. Therefore, further multi-centered studies in different parts of the country will be required to assess the re-emergence of sulfadoxine/pyrimethamine sensitive parasites and to monitor and prevent the establishment of multi drug resistant parasites in this region.

Return of chloroquine-sensitive Plasmodium falciparum parasites and emergence of chloroquine-resistant Plasmodium vivax in Ethiopia

BACKGROUND

Increased resistance by Plasmodium falciparum parasites led to the withdrawal of the antimalarial drugs chloroquine and sulphadoxine-pyrimethamine in Ethiopia. Since 2004 artemether-lumefantrine has served to treat uncomplicated P. falciparum malaria. However, increasing reports on delayed parasite clearance to artemisinin opens up a new challenge in anti-malarial therapy. With the complete withdrawal of CQ for the treatment of Plasmodium falciparum malaria, this study assessed the evolution of CQ resistance by investigating the prevalence of mutant alleles in the pfmdr1 and pfcrt genes in P. falciparum and pvmdr1 gene in Plasmodium vivax in Southern and Eastern Ethiopia.

METHODS

Of the 1,416 febrile patients attending primary health facilities in Southern Ethiopia, 329 febrile patients positive for P. falciparum or P. vivax were recruited. Similarly of the 1,304 febrile patients from Eastern Ethiopia, 81 febrile patients positive for P. falciparum or P. vivax were included in the study. Of the 410 finger prick blood samples collected from malaria patients, we used direct sequencing to investigate the prevalence of mutations in pfcrt and pfmdr1. This included determining the gene copy number in pfmdr1 in 195 P. falciparum clinical isolates, and mutations in the pvmdr1 locus in 215 P. vivax clinical isolates.

RESULTS

The pfcrt K76 CQ-sensitive allele was observed in 84.1% of the investigated P.falciparum clinical isolates. The pfcrt double mutations (K76T and C72S) were observed less than 3%. The pfcrt SVMNT haplotype was also found to be present in clinical isolates from Ethiopia. The pfcrt CVMNK-sensitive haplotypes were frequently observed (95.9%). The pfmdr1 mutation N86Y was observed only in 14.9% compared to 85.1% of the clinical isolates that carried sensitive alleles. Also, the sensitive pfmdr1 Y184 allele was more common, in 94.9% of clinical isolates. None of the investigated P. falciparum clinical isolates carried S1034C, N1042D and D1246Y pfmdr1 polymorphisms. All investigated P. falciparum clinical isolates from Southern and Eastern Ethiopia carried only a single copy of the mutant pfmdr1 gene.

CONCLUSION

The study reports for the first time the return of chloroquine sensitive P. falciparum in Ethiopia. These findings support the rationale for the use of CQ-based combination drugs as a possible future alternative.

High prevalence of pfcrt-CVIET haplotype in isolates from asymptomatic and symptomatic patients in south-central Oromia, Ethiopia

Background

As a result of extensive chloroquine resistance (CQR) in Plasmodium falciparum in late 1990s, Ethiopia replaced CQ with sulphadoxine-pyrimethamine (SP) as first-line drug, which in turn was replaced by artemisinin combination therapy in 2004. Plasmodium falciparum resistance to CQ is determined by the mutation at K76T of the P. falciparum chloroquine resistance transporter (pfcrt) gene. Understanding diversity in the P. falciparum genome is crucial since it has the potential to influence important phenotypes of the parasite such as drug resistance. Limited data is available regarding the type of pfcrt mutant allelic type, the effect of CQ withdrawal and diversity of the parasite population in south-central Oromia, Ethiopia.

Methods

Finger-pricked blood spotted on Whatman 3MM filter papers were collected from falciparum malaria patients. Parasite DNA was extracted from individual blood spots on the filter papers. The presence of K76T mutations was determined using nested PCR for all isolates. Complete sequencing of mutations in pfcrt 72-76 was done for a set of randomly selected resistant isolates. Four microsatellite (MS) markers were analysed to determine the heterozygosity.

Results

Although CQ was withdrawn for more than a decade, 100% of the parasites still carried the pfcrt K76T mutation. All isolates were mutant at the K76T polymorphism. Based on combinations of MS markers, seven different Ethiopian CQR variants (E1-E7) were identified. Heterozygosity (H_e) for MS flanking the pfcrt chloroquine resistance allele ranged from 0.00 (mscrt -29, -29.268 kb) to 0.21 (mscrt -2, -2.814 kb). H_e ranged from 0.00 (msint 3, 0 kb) to 0.19 (msint 2, 0 kb) for MS within the pfcrt gene. Both intronic and MS flanking the pfcrt gene showed low levels of diversity.

Conclusion

pfcrt CQR allele seems to be fixed in the study area. Of the different haplotypes associated with CQR, only the CVIET genotype was identified. No reversal to the wild-type has occurred in Ethiopia unlike in many Africa countries where CQR parasites declined after cessation of CQ use. Decreased diversity in CQR isolates surrounding pfcrt suggests CQ selection and homogenization among CQR parasite population. While mutation in msint 3 and mscrt -29 of the mutant pfcrt allele is being fixed, it seems that mutations in msint 2 and mscrt -2 are still evolving and may indicate the start of re-diversification of the population from a fixed 76 T population.

In vivo efficacy of artemether-lumefantrine and chloroquine against Plasmodium vivax: a randomized open label trial in central Ethiopia

BACKGROUND

In vivo efficacy assessments of antimalarials are essential for ensuring effective case management. In Ethiopia, chloroquine (CQ) without primaquine is the first-line treatment for Plasmodium vivax in malarious areas, but artemether-lumefantrine (AL) is also commonly used.

METHODS AND FINDINGS

In 2009, we conducted a 42-day efficacy study of AL or CQ for P. vivax in Oromia Regional State, Ethiopia. Individuals with P. vivax monoinfection were enrolled. Primary endpoint was day 28 cure rate. In patients with recurrent parasitemia, drug level and genotyping using microsatellite markers were assessed. Using survival analysis, uncorrected patient cure rates at day 28 were 75.7% (95% confidence interval (CI) 66.8-82.5) for AL and 90.8% (95% CI 83.6-94.9) for CQ. During the 42 days of follow-up, 41.6% (47/113) of patients in the AL arm and 31.8% (34/107) in the CQ arm presented with recurrent P. vivax infection, with the median number of days to recurrence of 28 compared to 35 days in the AL and CQ arm, respectively. Using microsatellite markers to reclassify recurrent parasitemias with a different genotype as non-treatment failures, day 28 cure rates were genotype adjusted to 91.1% (95% CI 84.1-95.1) for AL and to 97.2% (91.6-99.1) for CQ. Three patients (2.8%) with recurrent parasitemia by day 28 in the CQ arm were noted to have drug levels above 100 ng/ml.

CONCLUSIONS

In the short term, both AL and CQ were effective and well-tolerated for P. vivax malaria, but high rates of recurrent parasitemia were noted with both drugs. CQ provided longer post-treatment prophylaxis than AL, resulting in delayed recurrence of parasitemia. Although the current policy of species-specific treatment can be maintained for Ethiopia, the co-administration of primaquine for treatment of P. vivax malaria needs to be urgently considered to prevent relapse infections.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01052584.

Ten year trend analysis of malaria prevalence in Kola Diba, North Gondar, Northwest Ethiopia

BACKGROUND

Malaria is caused by protozoan parasites of the genus Plasmodium. It is one of the leading causes of illness and death in the world. It is a major public health problem in Ethiopia. Over the past years, the disease has been consistently reported as the first leading cause of outpatient visits, hospitalization and death in health facilities across the country.

METHODS

A retrospective study was conducted to determine the prevalence of malaria from peripheral blood smear examinations from the Kola Diba Health Center of Ethiopia. The case notes of all malaria cases reported between 2002-2011 were carefully reviewed and analyzed. Additionally, any malaria intervention activities that had been taken to control malaria were collected using a well-prepared checklist from the study area.

RESULTS

Within the last decade (2002-2011) a total of 59, 208 blood films were requested for malaria diagnosis in Kola Diba health center and 23,473 (39.6%) microscopically confirmed malaria cases were reported in the town with a fluctuating trend. Regarding the identified plasmodium species, Plasmodium falciparum and Plasmodium vivax accounted for 75% and 25% of malaria morbidity, respectively. Malaria was reported in all age groups and both sexes, but the 15-44 year age group and males were more affected. Despite the apparent fluctuation of malaria trends in the area, the highest peak of malaria cases was reported during spring seasons.

CONCLUSION

Comparatively, after the introduction of the current malaria control strategies, the morbidity and mortality by malaria is decreasing but malaria is still a major health problem and the deadly species P. falciparium is predominant. Therefore, control activities should be continued in a strengthened manner in the study area considering both P. falciparium and P. vivax.

In vivo efficacy of artemether-lumefantrine against uncomplicated Plasmodium falciparum malaria in Central Ethiopia

Background

In vivo efficacy assessments of the first-line treatments for Plasmodium falciparum malaria are essential for ensuring effective case management. In Ethiopia, artemether-lumefantrine (AL) has been the first-line treatment for uncomplicated P. falciparum malaria since 2004.

Methods

Between October and November 2009, we conducted a 42-day, single arm, open label study of AL for P. falciparum in individuals >6 months of age at two sites in Oromia State, Ethiopia. Eligible patients who had documented P. falciparum mono-infection were enrolled and followed according to the standard 2009 World Health Organization in vivo drug efficacy monitoring protocol. The primary and secondary endpoints were PCR uncorrected and corrected cure rates, as measured by adequate clinical and parasitological response on days 28 and 42, respectively.

Results

Of 4426 patients tested, 120 with confirmed falciparum malaria were enrolled and treated with AL. Follow-up was completed for 112 patients at day 28 and 104 patients at day 42. There was one late parasitological failure, which was classified as undetermined after genotyping. Uncorrected cure rates at both day 28 and 42 for the per protocol analysis were 99.1% (95% CI 95.1-100.0); corrected cure rates at both day 28 and 42 were 100.0%. Uncorrected cure rates at day 28 and 42 for the intention to treat analysis were 93.3% (95% CI 87.2-97.1) and 86.6% (95% CI 79.1-92.1), respectively, while the corrected cure rates at day 28 and 42 were 94.1% (95% CI 88.2-97.6) and 87.3% (95% CI 79.9-92.7), respectively. Using survival analysis, the unadjusted cure rate was 99.1% and 100.0% adjusted by genotyping for day 28 and 42, respectively. Eight P. falciparum patients (6.7%) presented with Plasmodium vivax infection during follow-up and were excluded from the per protocol analysis. Only one patient had persistent parasitaemia at day 3. No serious adverse events were reported, with cough and nausea/vomiting being the most common adverse events.

Conclusions

AL remains a highly effective and well-tolerated treatment for uncomplicated falciparum malaria in the study setting after several years of universal access to AL. A high rate of parasitaemia with P. vivax possibly from relapse or new infection was observed.

Trial Registration

NCT01052584

Climatic variables and malaria transmission dynamics in Jimma town, South West Ethiopia

BACKGROUND

In Ethiopia, malaria is seasonal and unstable, causing frequent epidemics. It usually occurs at altitudes < 2,000 m above sea level. Occasionally, transmission of malaria occurs in areas previously free of malaria, including areas > 2,000 m above sea level. For transmission of malaria parasite, climatic factors are important determinants as well as non-climatic factors that can negate climatic influences. Indeed, there is a scarcity of information on the correlation between climatic variability and malaria transmission risk in Ethiopia in general and in the study area in particular. Therefore, the aim of this study was to determine the level of correlation between meteorological variables and malaria cases.

METHODS

Time-series analysis was conducted using data on monthly meteorological variables and monthly total malaria in Jimma town, south west Ethiopia, for the period 2000-2009. All the data were entered and analyzed using SPSS-15 database program. Spearman correlation and linear regression analysis were used to asses association between the variables.

RESULTS

During last ten years (2000-2009), a fluctuating trend of malaria transmission was observed with P.vivax becoming predominant species. Spearman correlation analysis showed that monthly minimum temperature, total rainfall and two measures of relative humidity were positively related with malaria but monthly maximum temperature negatively related. Also regression analysis suggested that monthly minimum (p = 0.008), monthly maximum temperature (p = 0.013) and monthly total rainfall (p = 0.040), at one month lagged effect, were significant meteorological factors for transmission of malaria in the study area.

CONCLUSION

Malaria incidences in the last decade seem to have a significant association with meteorological variables. In future, prospective and multidisciplinary cooperative research involving researchers from the fields of parasitology, epidemiology, botany, agriculture and climatology is necessary to identify the real effect of meteorological factors on vector- borne diseases like malaria.

Confirmed vivax resistance to chloroquine and effectiveness of artemether-lumefantrine for the treatment of vivax malaria in Ethiopia

Chloroquine (CQ) is still the drug of choice for the treatment of vivax malaria in Ethiopia, whereas artemether-lumefantrine (AL) is for falciparum malaria. In this setting, clinical malaria cases are treated with AL. This necessitated the need to assess the effectiveness of AL for the treatment of Plasmodium vivax with CQ as a comparator. A total of 57 (80.3%) and 75 (85.2%) cases treated with CQ or AL, respectively, completed the study in an outpatient setting. At the end of the follow-up period of 28 days, a cumulative incidence of treatment failure of 7.5% (95% confidence interval [CI] = 2.9-18.9%) for CQ and 19% (95% CI = 11-31.6%) for AL was detected. CQ resistance was confirmed in three of five CQ treatment failures cases. The effectiveness of AL seems lower than CQ; however, the findings were not conclusive, because the AL evening doses were not supervised.

Therapeutic efficacy of Artemether/Lumefantrine (Coartem(R)) against Plasmodium falciparum in Kersa, South West Ethiopia

Background

Artemether/Lumefantrine (Coartem^®) has been used as a first-line treatment for uncomplicated Plasmodium falciparum infection since 2004 in Ethiopia. In the present study the therapeutic efficacy of artemether/lumefantrine for the treatment of uncomplicated P. falciparum infection at Kersa, Jima zone, South-west Ethiopia, has been assessed.

Methods

A 28 day therapeutic efficacy study was conducted between November 2007 and January 2008, in accordance with the 2003 WHO guidelines. Outcomes were classified as early treatment failure (ETF), late clinical failure (LCF), late parasitological failure (LPF) and adequate clinical and parasitological response (ACPR).

Results

90 patients were enrolled and completed the 28 day follow-up period after treatment with artemether/lumefantrine. Cure rate was very high, 96.3%, with 95% CI of 0.897-0.992 (PCR uncorrected). Age-stratified data showed adequate clinical and parasitological response (ACPR) to be 100% for children under 5 and 97.4% and 87.3% for children aged 5-14, and adults, respectively. There was no early treatment failure (ETF) in all age groups. Fever was significantly cleared on day 3 (P < 0.05) and 98% of parasites where cleared on day 1 and almost all parasites were cleared on day 3. 72.5% of gametocytes were cleared on day 1, the remaining 27.5% of gametocytes were maintained up to day 3 and total clearance was observed on day 7. Hemoglobin concentration showed a slight increase with parasitic clearance (P > 0.05). No major side effect was observed in the study except the occurrence of mouth ulcers in 7% of the patients.

Conclusions

The current study proved the excellent therapeutic efficacy of artemether/lumefantrine in the study area and the value of using it. However, the proper dispensing and absorption of the drug need to be emphasized in order to utilize the drug for a longer period of time. This study recommends further study on the toxicity of the drug with particular emphasis on the development of oral ulcers in children.

Impact of the large-scale deployment of artemether/lumefantrine on the malaria disease burden in Africa: case studies of South Africa, Zambia and Ethiopia

Malaria is one of the most significant causes of morbidity and mortality worldwide. Every year, nearly one million deaths result from malaria infection. Malaria can be controlled in endemic countries by using artemisinin-based combination therapy (ACT) in combination with indoor residual spraying (IRS) and insecticide-treated nets (ITNs). At least 40 malaria-endemic countries in sub-Saharan Africa now recommend the use of ACT as first-line treatment for uncomplicated falciparum malaria as a cornerstone of their malaria case management. The scaling up of malaria control strategies in Zambia has dramatically reduced the burden of malaria. Zambia was the first African country to adopt artemether/lumefantrine (AL; Coartem^®) as first-line therapy in national malaria treatment guidelines in 2002. Further, the vector control with IRS and ITNs was also scaled up. By 2008, the rates of in-patient malaria cases and deaths decreased by 61% and 66%, respectively, compared with the 2001-2002 reference period.

Treatment with AL as first-line therapy against a malaria epidemic in the KwaZulu-Natal province of South Africa, in combination with strengthening of vector control, caused the number of malaria-related outpatient cases and hospital admissions to each fall by 99% from 2001 to 2003, and malaria-related deaths decreased by 97% over the same period. A prospective study also showed that gametocyte development was prevented in all patients receiving AL. This reduction in malaria morbidity has been sustained over the past seven years.

AL was introduced as first-line anti-malarial treatment in 2004 in the Tigray region of Ethiopia. During a major malaria epidemic from May-October 2005, the district in which local community health workers were operating had half the rate of malaria-related deaths compared with the district in which AL was only available in state health facilities. Over the two-year study period, the community-based deployment of AL significantly lowered the risk of malaria-specific mortality by 37%. Additionally, the malaria parasite reservoir was three-fold lower in the intervention district than in the control district during the 2005 high-transmission season.

Artemisinin-based combination therapy has made a substantial contribution to reducing the burden of malaria in sub-Saharan Africa.

Chloroquine-resistant Plasmodium vivax malaria in Serbo town, Jimma zone, south-west Ethiopia

Background

Ethiopia has the highest proportion of vivax malaria, approximately 40% of all malaria infections, in contrast to African countries. Chloroquine (CQ) is the drug of choice for the treatment of Plasmodium vivax infection in the country, although CQ resistant P. vivax (CRPv) has started to challenge the efficacy of the drug. The present study was conducted to assess the current status of CRPv at Serbo, Jimma zone, south-west Ethiopia.

Methods

A 28-day in vivo therapeutic efficacy test was conducted from October 2007 to January 2008. Recurrence of parasitaemia and the clinical condition of patients were assessed on each visit during the follow-up. The levels of haemoglobin (Hb) in the study participants were determined. The patients' blood drug levels were measured using HPLC. Data was analysed using SPSS for windows version 10.0. HPLC data was computed using Chem Station for LC 3D systems software.

Results

Of the total 84 patients included in the study, 78 completed their 28-day follow-up, six of whom being excluded for different reasons. In three children (aged 7, 12 and 13 years), parasitaemia reappeared within the 28-days follow-up in spite of adequate absorption of the drug and absence of malaria symptom. In addition, on the day of recurrence of parasitaemia the levels of chloroquine-desethylchloroquine (CQ-DCQ) were above the minimum effective concentration (≥100 ηg/ml) in all the three cases, showing that treatment failure could not be attributed to low level of drug in the patients blood.

Conclusion

Reappearance of the parasite within the 28 days of follow-up is due to parasite resistance to CQ. The 3.6% (95% CI = -0.038 - 0.0758) prevalence of CRPv malaria in the study area signals the need for launching monitory activities for CQ resistant P. vivax. Moreover, as former report from the same country, Debrezeit, also showed the occurrence of CRPv, survey on CRPv malaria should be made in P. vivax endemic areas in order to estimate the level of burden across the country.

Malaria-related perceptions and practices of women with children under the age of five years in rural Ethiopia

BACKGROUND

Malaria remains to be the major cause of morbidity and mortality among pregnant women and children in Ethiopia. The aim of this study was to investigate the local perceptions, practices and treatment seeking behaviour for malaria among women with children under the age of five years.

METHODS

This community-based study was conducted in 2003 in an area of seasonal malaria transmission in Adami Tulu District, south-central Ethiopia. Total samples of 2087 rural women with children less than five years of age from 18 rural kebeles (the smallest administrative units) were interviewed about their perceptions and practices regarding malaria. In addition, focus group discussions and in-depth interviews were conducted on similar issues to complement the quantitative data.

RESULTS

Malaria, locally known as busaa, is perceived as the main health problem in the study area. Mosquitoes are perceived to be the main cause of the disease, and other misperceptions were also widespread. The use of prevention measures was very low. Most mothers were familiar with the main signs and symptoms of mild malaria, and some of them indicated high grade fever, convulsions and mental confusion as a manifestation of severe malaria. Very few households (5.6%) possessed one or two nets. More than 60% of the mothers with recent episodes of malaria received initial treatment from non-public health facilities such as community health workers (CHWs) (40%) and private care providers (21%). Less than 40% of the reported malaria cases among women were treated by public health facilities.

CONCLUSION

Malaria was perceived as the main health problem among women and children. The use of malaria preventive measures was low. A significant proportion of the respondents received initial malaria treatments from CHWs, private care providers and public health facilities. Concerted effort is needed to scale-up the distribution of insecticide-treated nets and improve the knowledge of the community about the link between malaria and mosquitoes. Effective antimalarial drugs should also be available at the grassroots level where the problem of malaria is rampant.

Chloroquine-resistant Plasmodium vivax malaria in Debre Zeit, Ethiopia

Background

Plasmodium vivax accounts for about 40% of all malaria infection in Ethiopia. Chloroquine (CQ) is the first line treatment for confirmed P. vivax malaria in the country. The first report of CQ treatment failure in P. vivax was from Debre Zeit, which suggested the presence of chloroquine resistance.

Methods

An in vivo drug efficacy study was conducted in Debre Zeit from June to August 2006. Eighty-seven patients with microscopically confirmed P. vivax malaria, aged between 8 months and 52 years, were recruited and treated under supervision with CQ (25 mg/kg over three days). Clinical and parasitological parameters were assessed during the 28 day follow-up period. CQ and desethylchloroquine (DCQ) blood and serum concentrations were determined with high performance liquid chromatography (HPLC) in patients who showed recurrent parasitaemia.

Results

Of the 87 patients recruited in the study, one was lost to follow-up and three were excluded due to P. falciparum infection during follow-up. A total of 83 (95%) of the study participants completed the follow-up. On enrolment, 39.8% had documented fever and 60.2% had a history of fever. The geometric mean parasite density of the patients was 7045 parasites/μl. Among these, four patients had recurrent parasitaemia on Day 28. The blood CQ plus DCQ concentrations of these four patients were all above the minimal effective concentration (> 100 ng/ml).

Conclusion

Chloroquine-resistant P. vivax parasites are emerging in Debre Zeit, Ethiopia. A multi-centre national survey is needed to better understand the extent of P. vivax resistance to CQ in Ethiopia.

Treatment-seeking behaviour for febrile illness in an area of seasonal malaria transmission in rural Ethiopia

BACKGROUND

Very little is known about the management of malaria and treatment-seeking patterns among children and adults in areas of seasonal malaria transmission particularly in east Africa.

OBJECTIVES

The aim of this study was to assess treatment-seeking behaviour for reported malaria among all age groups in an area of seasonal transmission.

METHODS

A community-based cross-sectional study was carried out among 2,253 households in 12 randomly selected rural kebeles in Adami Tulu district in south-central Ethiopia, during October-November 2003, using a pre-tested interviewer-administered structured questionnaire.

RESULTS

Reported malaria was 14% among 12,225 people assessed during the last 14 days. Family/self-diagnosis was most common and the main first responses included visiting village-based community health workers (CHWs) (33%), public health facility (23%) and private clinic (17%). Home treatment was the least reported first response (3%). Only 13% had sought treatment within the first 24 hours of symptom onset. Early treatment-seeking pattern was reported among those who visited CHWs and practiced home treatment, with more delays among public facility users. Treatment-seeking behaviour was similar in all age groups.

CONCLUSION

A considerable proportion of visits were made to CHWs and private providers, necessitating the importance of strengthening both community-based interventions and peripheral public and private facilities. Finally, the community should be informed and educated about the importance of early diagnosis and prompt treatment with effective antimalarials.

Intermittent preventive treatment for malaria in pregnancy in Africa: what's new, what's needed?

Falciparum malaria is an important cause of maternal, perinatal and neonatal morbidity in high transmission settings in Sub-Saharan Africa. Intermittent preventive treatment with sulphadoxine-pyrimethamine (SP-IPT) has proven efficacious in reducing the burden of pregnancy-associated malaria but increasing levels of parasite resistance mean that the benefits of national SP-IPT programmes may soon be seriously undermined in much of the region. Hence, there is an urgent need to develop alternative drug regimens for IPT in pregnancy. This paper reviews published safety and efficacy data on various antimalarials and proposes several candidate combination regimens for assessment in phase II/III clinical trials.

Malaria epidemics and interventions, Kenya, Burundi, southern Sudan, and Ethiopia, 1999-2004

Effectiveness was reduced by delays and other factors.

Quantitative data on the onset and evolution of malaria epidemics are scarce. We review case studies from recent African Plasmodium falciparum epidemics (Kisii and Gucha Districts, Kenya, 1999; Kayanza Province, Burundi, 2000–2001; Aweil East, southern Sudan, 2003; Gutten and Damot Gale, Ethiopia, 2003–2004). We highlight possible epidemic risk factors and review delays in epidemic detection and response (up to 20 weeks), essentially due to poor case reporting and analysis or low use of public facilities. Epidemics lasted 15–36 weeks, and patients' age profiles suggested departures from classical notions of epidemic malaria everywhere but Burundi. Although emergency interventions were mounted to expand inpatient and outpatient treatment access, we believe their effects were lessened because of delays, insufficient evaluation of disease burden, lack of evidence on how to increase treatment coverage in emergencies, and use of ineffective drugs.

High prevalence of drug-resistance mutations in Plasmodium falciparum and Plasmodium vivax in southern Ethiopia

BACKGROUND

In Ethiopia, malaria is caused by both Plasmodium falciparum and Plasmodium vivax. Drug resistance of P. falciparum to sulfadoxine-pyrimethamine (SP) and chloroquine (CQ) is frequent and intense in some areas.

METHODS

In 100 patients with uncomplicated malaria from Dilla, southern Ethiopia, P. falciparum dhfr and dhps mutations as well as P. vivax dhfr polymorphisms associated with resistance to SP and P. falciparum pfcrt and pfmdr1 mutations conferring CQ resistance were assessed.

RESULTS

P. falciparum and P. vivax were observed in 69% and 31% of the patients, respectively. Pfdhfr triple mutations and pfdhfr/pfdhps quintuple mutations occurred in 87% and 86% of P. falciparum isolates, respectively. Pfcrt T76 was seen in all and pfmdr1 Y86 in 81% of P. falciparum. The P. vivax dhfr core mutations N117 and R58 were present in 94% and 74%, respectively.

CONCLUSION

These data point to an extraordinarily high frequency of drug-resistance mutations in both P. falciparum and P. vivax in southern Ethiopia, and strongly support that both SP and CQ are inadequate drugs for this region.