MalariaWorld journal最新文献

Background: As many as 60-80% of people in developing countries first seek malaria treatment at private rather than public health facilities, but the technical quality of private services is questionable. Before commencing a Public Private Partnership for malaria, we wanted to assess the knowledge and practice of malaria diagnosis and treatment among healthcare providers (HCPs) working in Private Health Facilities (PHFs) in Ethiopia.

Materials and methods: A facility-based cross-sectional study was conducted from April to June 2012. Quantitative and qualitative data were collected, entered and analysed using SPSS version 20. We enrolled 264 HCPs from 264 PHFs in malaria-endemic towns.

Results: The majority (84.5%) of the HCPs were males, 106 (40%) were nurses and 135 (51.0%) had practiced for more than seven years. The knowledge of HCPs about the malaria programme was scored (from 1-5), and the mean was 2.52 (95% CI: 2.32-2.72), with 40.5% of the HCPs scoring above the mean. The majority knew the recommended treatment following confirmed diagnosis (91.3% for Plasmodium vivax, 88.6% for P. falciparum). 73.1% of suspected cases were investigated for parasitological diagnosis. The malaria slide positivity rate was 37.6%; however, only 60.0% of the confirmed cases were treated for malaria. Presumptive malaria treatment was offered to about 40% of patients. The adherence rate of HCPs towards prescribing the recommended first line drugs was 44.2% for chloroquine, 47.9% for ACTs and 77.9% for quinine.

Conclusions: The study revealed that in Ethiopia HCPs in private practices have major gaps in knowledge and practice related to malaria case management. Therefore, provision of malaria diagnosis and case management training, supportive supervision and job aids is recommended for private healthcare providers, especially for nurses and for younger healthcare professionals.

Background: Placental malaria has long been acknowledged as a complication of malaria in pregnancy, and has been associated with poor pregnancy outcome in malaria-endemic areas. This study was conducted to determine the risk factors associated with occurrence of placental malaria in a population of parturients in Abeokuta Ogun State, Nigeria.

Materials and methods: Maternal and placenta blood samples were collected from 211 parturients. Blood films were prepared, stained with 10% Giemsa and microscopically analysed for the presence of parasites. Demographic characteristics were recorded in case record forms. Chi-square tests and a regression model were computed to analyse risks, using SPSS version 16.0.

Results: Overall, 40.8% (86 of 211) of the parturients had malaria at the time of delivery, with 19.0% (40 of 211) having placental malaria. We identified being within the age range of 18-22 years [OR = 4.4, 95% CL = 1.1-17.4, P = 0.046], being primigravid [OR = 2.1, 95% CL = 0.9-5.1, P = 0.028] and living in a congested apartment [OR = 1.6, 95% CL = 0.4-6.0, P = 0.029] as significant risk factors for placental malaria. Non-usage of intermittent preventive treatment (IPT) [OR = 2.6, 95% CL = 1.2-5.4, P = 0.018], long-lasting insecticidal nets (LLINs) [OR = 2.7, 95% CL = 1.3-5.5, P = 0.005] were also risk factors for placental malaria.

Conclusions: In Abeokuta, the proper use of LLIN and IPT for pregnant women is essential to curb the scourge of malaria, associated risks and poor pregnancy outcomes.

Background: Febrile illnesses are common causes of morbidity and mortality among under-five children in sub-Saharan Africa. The recommended strategy for effective case management of uncomplicated malaria is parasitological confirmation prior to use of artemisinin-based combination therapy (ACT). There is a lack of qualitative information explaining factors, which influence malaria case management practices among health workers. This study explores the perceptions of health managers and health care providers on the case management of uncomplicated malaria among under-fives in selected primary health care (PHC) facilities of two Local Government Areas (LGAs), Katcha and Gbako, as part of baselines for capacity-building interventions planned in Niger State, Nigeria.

Methods: Interviewees included state- and LGA-level health programme managers, and frontline health workers purposively selected to cover a range of cadres involved in case management of sick children. Issues explored were history taking, diagnosis, appropriate diagnosis of malaria, prescription for malaria, referrals and adherence to referral. Data coding was carried out with Nvivo qualitative software (version 8) and content analysed.

Results: History taking was often not carried out appropriately by the health workers. Treatment of malaria was not based on parasite-based diagnosis. Most of the health workers reported that they prescribed ACTs for treating presumed uncomplicated malaria. Care givers' preferences, poor transportation systems and lack of financial resources led to poor adherence to referral advice. Absence of health workers from their duty post hindered effective service delivery. Prescription of ACTs as a first line of treatment for uncomplicated malaria without a parasite-based diagnosis was the standard case management practice.

Conclusion: Parasite-based diagnosis for malaria will invariably lead to better treatment for non-malaria fever cases among the studied age group. Continuous capacity building aimed at improving adherence to current recommendations on parasite-based diagnosis and good clinical practice would be required to support the paradigm shift to parasite-based diagnosis of malaria.

Background: The accuracy of malaria diagnosis by microscopy has been a challenge in health facilities in Nigeria due to poor competence of microscopists and inability to report on malaria species other than Plasmodium falciparum. Short microscopy courses were conducted to improve the skills of laboratory personnel to perform malaria microscopy in public health facilities in Nigeria.

Materials and methods: Seven-day malaria microscopy courses were conducted annually between 2011 and 2013 for microscopists in public health facilities. The training courses contained theoretical and practical sessions. Impact of the training was evaluated by practical and theoretical pre- and post-training assessments on malaria slide reading, parasite enumeration and basic malariology.

Results: The 102 participants who completed the training consisted of medical laboratory scientists (62; 60.8%), medical laboratory technicians (24; 23.5%) and other healthcare workers (16; 15.7%). The knowledge of basic malariology (theory) at pre- and post-tests were 34% (95% CI 31.7-36.3%) and 74.9% (95% CI 71.8-78.0%), respectively (P<0.001). The mean slide reading detection, species and counting agreements in pre-training assessment were 48.9%, 27.9% and 0%, respectively, and in post-training 56.8%, 39.2% and 25%, respectively. The mean species agreements in picture test pre- and post-training were 21.9% and 55.1%, respectively. There were significant differences (P<0.05) in the median pre-test scores in picture tests and basic malariology of the three categories of participants but not in malaria slide reading and parasite counting tests. However, post-training, a significant difference in test scores of the three categories of participants was recorded only for basic malariology (P=0.0003).

Conclusions: The 7-day malaria microscopy courses significantly increased the knowledge and microscopy skills of the trainees and were sufficient to bridge the significant difference in baseline microscopy skills of the different categories of trainees that participated in the training courses.

Background: Malaria is one of the most important causes of mortality worldwide. Use of the most effective treatments remains inadequate for those in need and there is concern over the emergence of resistance. Rapid, accurate and accessible detection of malaria parasites plays a role in promoting more rational use of increasingly costly drugs in many endemic areas. Rapid diagnostic tests (RDTs) offer the potential to provide accurate diagnosis to all at-risk populations for the first time, reaching those unable to access good quality microscopy services. In 2010, the Global Fund launched the Affordable Medicines Facility for malaria (AMFm) designed to increase access and use of good quality artemisinin-based combination therapies (ACTs) for malaria treatment. AMFm involves manufacturer price negotiations, subsidies and other interventions. The aim of this study was to document the availability of ACTs and RDTs provided under the National Malaria Elimination Programme via the AMFm financing strategy.

Materials and methods: Investigators were systematically selected and trained on the data collection tool from the World Health Organization/Health Action International (WHO/HAI) Workbook. Data was collected from public and private facilities in 12 states in the six geopolitical zones of Nigeria in April and May 2014. Returned survey forms were checked, entered and verified. Data analysis was carried out using the embedded analysis toolkit in the WHO/HAI Workbook after double-entry and auto-checking of data. Data was analysed for the public and private sectors.

Results: Seven AMFm products are available in the country, and include AL (IPCA), Artemef (Cipla), Coartem AMFm (Novartis), Combisunate (Ajanta), Lumartem (Cipla) as well as Arsuamoon (Guilin) and Coarsucam (Sanofi-Winthrop). The results reveal that antimalarials are largely concentrated in the private sector (private pharmacies and PPMVs). About 86% of the surveyed facilities had at least one AMFm AL product whereas only 18% had any AMFm AA product. Results show that the availability of the various AMFm AL products varies across the country. Lumartem by Cipla has the highest national availability with 26.4%, closely followed by AL (IPCA) with 25.7%. Twenty seven (%) of the facilities had an RDT in stock.

Conclusion: The results obtained in this survey show that continuous monitoring of the antimalarial drug landscape is required to track progress in the fight against malaria in the country.

Background: L-buthionine (S,R)-sulfoximine (BSO) regulates the glutathione (GSH) level, which in turn exhibits remarkable regulation of several important aspects of cellular metabolism. We hypothesised that increasing the cellular levels of glutathione leads to an increased resistance to arteether, whereas decreasing these by using a GSH inhibitor increases the parasite sensitivity to arteether in the rodent malaria parasite Plasmodium vinckei.

Materials and methods: We tested in vivo effects of BSO on GSH and hemozoin formation in arteether-sensitive and - resistant strains. Experimental groups of 7-8 Swiss mice were inoculated by intraperitoneal injection (i.p.) with 1×10⁶ parasitized erythrocytes of PvAS (sensitive) or PvAR (resistant) strain of P. vinckei. The infected mice were treated with BSO (Sigma) 400 mg/kg twice a day for four days and blood was collected after the last injection with BSO.

Results: A relatively stronger inhibition of GSH level was observed in the blood of mice infected with resistant parasites (62.64%; p<0.0001), whereas inhibition in sensitive strain-infected mice and uninfected mice was 32% (p=0.034) and 35% (p=0.034), respectively. The results also show an inverse relationship between GSH and hemozoin in the arteether-sensitive and -resistant strains. The hemozoin contents in the resistant strain are 0.27±0.09, 0.69±0.14 and 5.30±0.79 μmol/10⁹ cells at 5, 10 and 20% parasitemia, respectively, whereas hemozoin contents in the sensitive strain at the same parasitemia levels are 0.59±0.29, 12.38±1.96 and 30.80±2.27 μmol/10⁹ cells. Moreover, hemozoin formation increased by 80% through the administration of BSO in the arteether-resistant strain, whereas insignificant changes occurred in the sensitive strain. BSO was also found to increase the efficacy of arteether antimalarial activity against the resistant strain in vivo.

Conclusions: Treatment with BSO significantly reduces the level of GSH, which leads to insufficient growth of resistant parasites. These results suggest that BSO might be helpful in prolonging the persistence of the drug, and pose a promising lead to help reducing the chance of resistance development against artemisinin and its derivatives.

Background: Drug resistance has been one of the main obstacles in the fight against vector-borne infectious diseases. Among these diseases, malaria represents a serious public health challenge, mainly in the tropics, where vector-favourable climates are a crucial factor. Each of the various anti-malarial drugs currently used against this disease, such as quinolones, sulphonamides and artemisinins are inadequate and new strategies are required. Peptides are known to have a huge number of biological effects. Antimicrobial peptides (AMPs) have been proven to be effective against bacterial, fungal and viral infections. This study explored the effect of the peptide 'deltorphin-II' in Plasmodium berghei-infected mice.

Materials and methods: Mean percentage parasitaemia was calculated by studying infected erythrocytes after microscopic examination of 10⁴ erythrocytes from infected mice on days 4, 7, 10, 14 and 21 after infection in all groups. Results. Deltorphin-II shows maximum activity at a dose of 0.8 mg/kg/day from day 4 to day 21. Pre-treatment of infected mice with naltriben abrogates the deltorphin-II-mediated effect.

Conclusion: Deltorphin-II inhibits the development of malaria, most probably via activation of the δ₂ receptor.

Background: Malaria vaccine is a potentially effective addition to the armamentarium for malaria control. The candidate RTS,S malaria vaccine has undergone phase III clinical trials and WHO has indicated that a policy recommendation is possible in 2015. Given the delays with adoption of other novel interventions including vaccines, there is a need to ensure that all elements that will inform the decision to adopt a malaria vaccine, including community willingness, will be available on time. This study was carried out to assess the willingness of caregivers of under-5 children to accept a malaria vaccine once available and recommended for use.

Materials and methods: 427 consenting caregivers, selected using a cluster sampling technique, from five communities in Ibadan, Nigeria, participated in a questionnaire. In-depth interviews (IDIs) were conducted among 47 key community members. Data were analysed using descriptive statistics, Chi-square and logistic regression at p≤0.05. Thematic content analysis was used to analyse the transcribed IDI data.

Results: The mean age of survey respondents was 29.8±5.8 years. Only 20.1% of the respondents had ever heard of malaria vaccine; 87.0% showed willingness to accept a malaria vaccine. Reasons stated for not willing included 'husband did not want immunisation' (73.6%), 'felt it might be expensive' (47.2%) and 'felt it might paralyse children' (24.5%). Nearly half (48.7%) of the respondents said that if vaccine is not given orally like polio vaccine it might not be accepted. Influence of community health workers was found to predict willingness to accept a malaria vaccine (OR: 0.316, 95% CI: 0.142-0.705). IDI participants were favourably disposed to introduction of a vaccine against malaria, although they had concerns about the formulation of the vaccine and possible adverse events.

Conclusion: Well-designed communication strategies implemented prior to the introduction of a malaria vaccine would be essential to foster a supportive environment for eventual adoption and acceptance thereof.

Background: The mermithid nematode Romanomermis iyengari is one of several natural control alternatives to synthetic pesticides for mosquito suppression. The commonly used mass rearing procedure of R. iyengari involves the use of coarse sand as a substrate for nematode maturation and oviposition. The coarse sand technique gives excellent nematode productivity in North America. However, under West African climatic conditions, this technique generates relatively lesser amounts of infectious worms. We evaluated coconut coir fibres as a replacement for coarse sand to improve yields in large-scale production of R. iyengari in Benin, West Africa.

Materials and methods: Culex quinquefasciatus was the host for the nematodes, and mosquitoes were blood-fed on chickens. Four days after blood feeding, egg rafts were collected and transferred into trays, each containing 2 l of water. The mosquito larvae were fed with fish food. When the mosquito larvae reached the second instar, preparasites (J2) were added (3 J2/larva) to the incubation trays. Eight days after infection, post-parasitic juveniles were separated from the water containing dead mosquito larvae and other debris using sieves and needles; 2 g of them were deposited in containers with coarse sand or coconut coir fibres and water. Three hours later, the water was drained, the jars covered and stored for eight weeks, after which J2 abundance was determined, using a total of 320 containers for each substrate. The abundance of J2 preparasites was also assessed 3-5 months after storage to determine the impact of long-term storage on the J2 yield.

Results: After 2 months storage, 2 g of post-parasites (~457 females and 583 males) yielded an average of 559,300±6094 J2 and 155,818±4427 J2 per container for coconut fibres and for coarse sand, respectively. During long-term storage, yields of J2 on coconut fibres substrate slowly decreased from 442,180±9322 J2 (3 months storage) to 163,632±12,416 J2 per container (5 months storage). On coarse sand substrate, the yield was relatively low and decreased from 49,812±1200 J2 at 3 months storage to 3046±229 J2 at 5 months storage.

Conclusion: Under West African climatic conditions, coconut coir fibres gave significantly higher preparasitic nematode yields than the coarse sand technique.

Background: In Africa, malaria care is mostly based on clinical presumption and the general application of antimalarial treatment to all febrile episodes over several years. Treatment limited to confirmed cases might curb the practice of equating fever with malaria, antimalarial drug abuse and the extension of Plasmodium resistance, provided that powerful and reliable rapid diagnostic tests are used. This study aimed at determining the performances of the Optimal-IT^® test in the strategy for the exclusive treatment of uncomplicated malaria in rural areas.

Materials and methods: A prospective study conducted in the forest region of San Pedro, Côte d'Ivoire, included patients exhibiting clinical signs of uncomplicated malaria who gave their consent and benefited from thick blood film (TBF), blood smear (BS) and Optimal-IT^® (pLDH-based) test. Rapid diagnostic test (RDT) results were taken into consideration to decide on malaria treatment and then compared with TBF/BS results (reference) to assess the performances and clinical usefulness of the RDT.

Results: The mean age of the 384 patients included (209 men, 175 women) was 28 years and the mean temperature was 38.1°C. TBF/BS and Optimal-IT^® were concordant in 92% of patients but discordant in 10 false negative (3%) and 19 false-positive patients (5%). The average parasite density of P. falciparum was 25,600 trophozoites/μl. The performances calculated were: sensitivity=95%, specificity=91%, positive predictive value=90%, negative predictive value=95%, positive likelihood ratio=10, negative likelihood ratio=0.06 and diagnostic odds ratio=166, indicating that Optimal-IT^® is a powerful and credible diagnostic tool. The 193 RDT-positive patients treated were healed, despite three recurrence cases at day (D) D₁₇, D₂₅ and D₂₇, respectively. RDT-negative patients received various treatments (antibiotics, paracetamol), but two patients among them presented with a bout of malaria on D₇. None of the previously untreated patients returned with severe malaria.

Conclusions: The Optimal-IT^® test, which is already used in the field, showed good performances to effectively detect patients with and without malaria. It is therefore adapted to the malaria treatment strategy limited to confirmed cases.