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Publication Metadata only Village malaria worker performance key to the elimination of artemisinin-resistant malaria: A Western Cambodia health system assessment(2016-05-20) Sara E. Canavati; Saranath Lawpoolsri; Cesia E. Quintero; Chea Nguon; Po Ly; Sasithon Pukrittayakamee; David Sintasath; Pratap Singhasivanon; Koen Peeters Grietens; Maxine Anne Whittaker; Mahidol University; Burnet Institute; Ministry of Health Cambodia; Prins Leopold Instituut voor Tropische Geneeskunde; Nagasaki University; Partners for Applied Social Sciences (PASS) International; James Cook University, Australia; University of Queenslandcommunication interventions to this target population. This study aimed to assess the job performance of VMWs/MMWs, and identify challenges they face, which may impede elimination efforts. Methods: A mixed-methods assessment was conducted in five provinces... satisfaction also affected job performance. Discussion: VMW/MMW job performance must be increased from 80 to 100 % in order to achieve elimination. In order to do this, it is recommended for the national malaria programme to eliminate worker malaria knowledgePublication Open Access Spatio-temporal patterns of malaria infection in Bhutan: a country embarking on malaria elimination(2011-04-16) Wangdi, Kinley; Jaranit Kaewkungwal; จรณิต แก้วกังวาล; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Tassanee Silawan; Saranath Lawpoolsri; สารนาถ ล้อพูลศรี; White, Nicholas J.; Wangdi, Kinley; Mahidol University. Faculty of Tropical Medicine. Department of Tropical Hygiene.in implementing the control activities. Poisson regression was performed to study the trend of malaria incidences at district level from 1994 to 2008. Spatial Empirical Bayesian smoothing was deployed to identify clusters of malaria at the sub-district levelPublication Open Access Artemisinin resistance containment project in Thailand. II: Responses to mefloquine-artesunate combination therapy among falciparum malaria patients in provinces bordering Cambodia(2012-08-28) Wichai Satimai; Prayuth Sudathip; Saowanit Vijaykadga; Amnat Khamsiriwatchara; อำนาจ คำศิริวัชรา; Surasak Sawang; Thanapon Potithavoranan; Aumnuyphan Sangvichean; Delacollette, Charles; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Jaranit Kaewkungwal; จรณิต แก้วกังวาล; Saranath Lawpoolsri; สารนาถ ล้อพูลศรี; Saranath Lawpoolsri; Mahidol University. Faculty of Tropical Medicine. Department of Tropical Hygiene; Mahidol University. Faculty of Tropical Medicine. Center of Excellence for Biomedical and Public Health Informatics (BIOPHICS). Statistical analysis was performed to determine the cure rate of the current standard anti-malarial drug regimen--mefloquine-artesunate combination therapy (MAS). The proportion of patients who remained parasite-positive at each follow-up dayPublication Open Access Artemisinin resistance containment project in Thailand. (I): Implementation of electronic-based malaria information system for early case detection and individual case management in provinces along the Thai-Cambodian border(2012-07-29) Amnat Khamsiriwatchara; Prayuth Sudathip; Surasak Sawang; Saowanit Vijakadge; Thanapon Potithavoranan; Aumnuyphan Sangvichean; Wichai Satimai; Delacollette, Charles; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Saranath Lawpoolsri; สารนาถ ล้อพูลศรี; Jaranit Kaewkungwal; จรณิต แก้วกังวาล; Jaranit Kaewkungwal; Mahidol University. Faculty of Tropical Medicine. Department of Tropical Hygiene; Mahidol University. Faculty of Tropical Medicine. Center of Excellence for Biomedical and Public Health Informatics.BACKGROUND: The Bureau of Vector-borne Diseases, Ministry of Public Health, Thailand, has implemented an electronic Malaria Information System (eMIS) as part of a strategy to contain artemisinin resistance. The attempt corresponds to the WHO initiative, funded by the Bill & Melinda Gates Foundation, to contain anti-malarial drug resistance in Southeast Asia. The main objective of this study was to demonstrate the eMIS' functionality and outputs after implementation for use in the Thailand artemisinin-resistance containment project. METHODS: The eMIS had been functioning since 2009 in seven Thai-Cambodian border provinces. The eMIS has covered 61 malaria posts/clinics, 27 Vector-borne Disease Units covering 12,508 hamlets at risk of malaria infections. The eMIS was designed as an evidence-based and near real-time system to capture data for early case detection, intensive case investigation, monitoring drug compliance and on/off-site tracking of malarial patients, as well as collecting data indicating potential drug resistance among patients. Data captured by the eMIS in 2008-2011 were extracted and presented. RESULTS: The core functionalities of the eMIS have been utilized by malaria staff at all levels, from local operational units to ministerial management. The eMIS case detection module suggested decreasing trends during 2009-2011; the number of malaria cases detected in the project areas over the years studied were 3818, 2695, and 2566, with sero-positive rates of 1.24, 0.98, and 1.16%, respectively. The eMIS case investigation module revealed different trends in weekly Plasmodium falciparum case numbers, when classified by responsible operational unit, local and migrant status, and case-detection type. It was shown that most Thai patients were infected within their own residential district, while migrants were infected either at their working village or from across the border. The data mapped in the system suggested that P. falciparum-infected cases and potential drug-resistant cases were scattered mostly along the border villages. The mobile technology application has detected different follow-up rates, with particularly low rates among seasonal and cross-border migrants. CONCLUSION: The eMIS demonstrated that it could capture essential data from individual malaria cases at local operational units, while effectively being used for situation and trend analysis at upper-management levels. The system provides evidence-based information that could contribute to the control and containment of resistant parasites. Currently, the eMIS is expanding beyond the Thai-Cambodian project areas to the provinces that lie along the Thai-Myanmar border.Publication Open Access Chloroquine resistant vivax malaria in a pregnant woman on the western border of Thailand(2011-05-05) Rijken, Marcus J.; Boel, Machteld E.; Russell, Bruce; Mallika Imwong; มัลลิกา อิ่มวงศ์; Leimanis, Mara L.; Phyo, Aung Pyae; Muehlenbachs, Atis; Lindegardh, Niklas; McGready, Rose; Rénia, Laurent; Snounou, Georges; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Nosten, François; Rijken, Marcus J.; Mahidol University. Faculty of Tropical Medicine.Department of Molecular Tropical Medicine and GeneticsChloroquine (CQ) resistant vivax malaria is spreading. In this case, Plasmodium vivax infections during pregnancy and in the postpartum period were not satisfactorily cleared by CQ, despite adequate drug concentrations. A growth restricted infant was delivered. Poor susceptibility to CQ was confirmed in-vitro and molecular genotyping was strongly suggestive of true recrudescence of P. vivax. This is the first clinically and laboratory confirmed case of two high-grade CQ resistant vivax parasite strains from Thailand.Publication Open Access Dihydroartemisinin-piperaquine versus chloroquine to treat vivax malaria in Afghanistan: an open randomized,non-inferiority, trial(2010-04) Awab, Ghulam Rahim; Sasithon Pukrittayakamee; ศศิธร ผู้กฤตยาคามี; Mallika Imwong; มัลลิกา อิ่มวงศ์; Dondorp, Arjen M.; Woodrow, Charles J.; Lee, Sue Jean; Day, Nicholas P.J.; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; White, Nicholas J.; Kaker, Faizullah; White, Nicholas J.; Mahidol University. Faculty of Tropical MediicneBACKGROUND: Afghanistan's national guidelines recommend chloroquine for the treatment of Plasmodium vivax infection, the parasite responsible for the majority of its malaria burden. Chloroquine resistance in P. vivax is emerging in Asia. Therapeutic responses across Afghanistan have not been evaluated in detail. METHODS: Between July 2007 and February 2009, an open-label, randomized controlled trial of chloroquine and dihydroartemisinin-piperaquine in patients aged three months and over with slide-confirmed P. vivax mono-infections was conducted. Consistent with current national guidelines, primaquine was not administered. Subjects were followed up daily during the acute phase of illness (days 0-3) and weekly until day 56. The primary endpoint was the overall cumulative parasitological failure rate at day 56 after the start of treatment, with the hypothesis being that dihydroartemisinin-piperaquine was non-inferior compared to chloroquine (Delta = 5% difference in proportion of failures). RESULTS: Of 2,182 individuals with positive blood films for P. vivax, 536 were enrolled in the trial. The day 28 cure rate was 100% in both treatment groups. Parasite clearance was more rapid with dihydroartemisinin-piperaquine than chloroquine. At day 56, there were more recurrent infections in the chloroquine arm (8.9%, 95% CI 6.0-13.1%) than the dihydroartemisinin-piperaquine arm (2.8%, 95% CI 1.4-5.8%), a difference in cumulative recurrence rate of 6.1% (2-sided 90%CI +2.6 to +9.7%). The log-rank test comparing the survival curves confirmed the superiority of dihydroartemisinin-piperaquine over chloroquine (p = 0.003). Multivariate analysis showed that a lower initial haemoglobin concentration was also independently associated with recurrence. Both regimens were well tolerated and no serious adverse events were reported. CONCLUSIONS: Chloroquine remains an efficacious treatment for the treatment of vivax malaria in Afghanistan. In a setting where radical therapy cannot be administered, dihydroartemisinin-piperaquine provides additional benefit in terms of post-treatment prophylaxis, reducing the incidence of recurrence from 4-8 weeks after treatment.Publication Open Access The impact of human reservoir of malaria at a community-level on individual malaria occurrence in a low malaria transmission setting along the Thai-Myanmar border(2010-05) Saranath Lawpoolsri; สารนาถ ล้อพูลศรี; Chavez, Irwin F.; Surapon Yimsamran; สุรพล ยิ้มสำราญ; Supalap Puangsa-art; สุภลาภ พวงสอาด; Nipon Thanyavanich; นิพนธ์ ธัญญวานิช; Wanchai Maneeboonyang; Wuthichai Chaimungkun; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Maguire, James H.; Hungerford, Laura L.; Saranath Lawpoolsri; Mahidol University. Faculty of Tropical Medicine. Department of Tropical HygieneBACKGROUND: The probability of contracting malaria in a given individual is determined not only by the individual's characteristics, but also the ecological factors that characterize the level of human-vector contact in the population. Examination of the relationship between "individual" and "supra-individual" variables over time is important for understanding the local malaria epidemiology. This is essential for planning effective intervention strategies specifically for each location. METHODS: A retrospective cohort study was conducted, which followed a community-cohort of about 3,500 residents in seven hamlets along the Thai-Myanmar border between 1999 and 2006. Potential malaria determinants measured at different levels (temporal variables, individual variables, and hamlet variables) were incorporated into multilevel models to estimate their effects on an individual's risk of malaria attack. RESULTS: The monthly minimum temperature was significantly associated with the seasonal variation of malaria risk. An individual risk of malaria attack decreased by about 50% during the period that active surveillance was conducted; an additional 15% and 25% reduction of Plasmodium falciparum and Plasmodium vivax incidence, respectively, was observed after the use of artesunate-mefloquine combination therapy (ACT) for treatment of P. falciparum. Male children (age < 16 years old) were at highest risk of both P. falciparum and P. vivax attack. An increase in the hamlet's incidence of P. falciparum and P. vivax by 1 per 100 persons in a previous month resulted in 1.14 and 1.34 times increase in the risk of P. falciparum and P. vivax, respectively, among individuals in a particular hamlet. CONCLUSION: In a small area with low malaria transmission intensity, the variation in mosquito abundance is relatively similar across the residential areas; incidence of malaria between hamlets, which reflects the community level of human infectious reservoirs, is an important predictor for the malaria risk among individuals within these hamlets. Therefore, local malaria control strategies should focus on interventions that aim to reduce the gametocyte carriage in the population, such as early detection and treatment programmes and the use of ACT for P. falciparum.Publication Open Access The effects of serum lipids on the in vitro activity of lumefantrine and atovaquone against Plasmodium falciparum(2012-05-28) Kesinee Chotivanich; เกศินี โชติวานิช; Mathirut Mungthin; มฑิรุทธ มุ่งถิ่น; Ronnatrai Ruengweerayuth; Rachanee Udomsangpetc; รัชนีย์ อุดมแสงเพ็ชร; Dondorp, Arjen M.; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Sasithon Pukrittayakamee; ศศิธร ผู้กฤตยาคามี; White, Nicholas J.; White, Nicholas J.; Mahidol University. Faculty of Tropical Medicine. Mahidol-Oxford Tropical Medicine Research Unit; Mahidol University. Faculty of Science. Department of PathobiologyBACKGROUND: Lumefantrine and atovaquone are highly lipophilic anti-malarial drugs. As a consequence absorption is increased when the drugs are taken together with a fatty meal, but the free fraction of active drug decreases in the presence of triglyceride-rich plasma lipoproteins. In this study, the consequences of lipidaemia on anti-malarial drug efficacy were assessed in vitro. METHODS: Serum was obtained from non-immune volunteers under fasting conditions and after ingestion of a high fat meal and used in standard Plasmodium falciparum in-vitro susceptibility assays. Anti-malarial drugs, including lumefantrine, atovaquone and chloroquine in five-fold dilutions (range 0.05 ng/ml-1 ug/mL) were diluted in culture medium supplemented with fasting or post-prandial 10% donor serum. The in-vitro drug susceptibility of parasite isolates was determined using the ³H-hypoxanthine uptake inhibition method and expressed as the concentration which gave 50% inhibition of hypoxanthine uptake (IC₅₀). RESULTS: Doubling plasma triglyceride concentrations (from 160 mg/dL to 320 mg/dL), resulted in an approximate doubling of the IC₅₀ for lumefantrine (191 ng/mL to 465 ng/mL, P < 0.01) and a 20-fold increase in the IC₅₀ for atovaquone (0.5 ng/mL to 12 ng/ml; P < 0.01). In contrast, susceptibility to the hydrophilic anti-malarial chloroquine did not change in relation to triglyceride content of the medium. CONCLUSIONS: Lipidaemia reduces the anti-malarial activity of lipophilic anti-malarial drugs. This is an important confounder in laboratory in vitro testing and it could have therapeutic relevance.Publication Open Access Are there any changes in burden and management of communicable diseases in areas affected by Cyclone Nargis?(2011-06-28) Myint, Nyan Win; Jaranit Kaewkungwal; จรณิต แก้วกังวาล; Pratap Singhasivanon; ประตาป สิงหศิวานนท์; Kamron Chaisiri; Pornpet Panjapiyakul; Pichit Siriwan; Mallik, Arun K.; Nyein, Soe Lwin; Mu, Thet Thet; Jaranit Kaewkungwal; Mahidol University. Faculty of Tropical MedicineBACKGROUND: This study aims to assess the situation of communicable diseases under national surveillance in the Cyclone Nargis-affected areas in Myanmar (Burma) before and after the incident. METHODS: Monthly data during 2007, 2008 and 2009 from the routine reporting system for disease surveillance of the Myanmar Ministry of Health (MMOH) were reviewed and compared with weekly reporting from the Early Warning and Rapid Response (EWAR) system. Data from some UN agencies, NGOs and Tri-Partite Core Group (TCG) periodic reviews were also extracted for comparisons with indicators from Sphere and the Inter-Agency Standing Committee. RESULTS: Compared to 2007 and 2009, large and atypical increases in diarrheal disease and especially dysentery cases occurred in 2008 following Cyclone Nargis. A seasonal increase in ARI reached levels higher than usual in the months of 2008 post-Nargis. The number of malaria cases post-Nargis also increased, but it was less clear if this reflected normal seasonal patterns or was specifically associated with the disaster event. There was no significant change in the occurrence of other communicable diseases in Nargis-affected areas. Except for a small decrease in mortality for diarrheal diseases and ARI in 2008 in Nargis-affected areas, population-based mortality rates for all other communicable diseases showed no significant change in 2008 in these areas, compared to 2007 and 2009. Tuberculosis control programs reached their targets of 70% case detection and 85% treatment success rates in 2007 and 2008. Vaccination coverage rates for DPT 3rd dose and measles remained at high though measles coverage still did not reach the Sphere target of 95% even by 2009. Sanitary latrine coverage in the Nargis-affected area dropped sharply to 50% in the months of 2008 following the incident but then rose to 72% in 2009. CONCLUSION: While the incidence of diarrhea, dysentery and ARI increased post-Nargis in areas affected by the incident, the incidence rate for other diseases and mortality rates did not increase, and normal disease patterns resumed by 2009. This suggests that health services as well as prevention and control measures provided to the Nargis-affected population mitigated what could have been a far more severe health impact.