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1.
Malar J ; 22(1): 302, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37814267

RESUMO

BACKGROUND: Plasmodium vivax malaria is considered a major threat to malaria eradication. The radical cure for P. vivax malaria normally requires a 14-day administration of primaquine (PQ) to clear hypnozoites. However, maintaining adherence to PQ treatment is a significant challenge, particularly in malaria-endemic rural areas. Hence, this study aimed to formulate interventions for promoting patients' commitment to PQ treatment in a highly malaria-endemic township in Myanmar. METHODS: A qualitative study was conducted in Waingmaw Township in northern Myanmar, where P. vivax malaria is highly endemic. Key stakeholders including public health officers and community members participated in focus group discussions (FGDs) and in-depth interviews (IDIs) in September 2022. Data were collected using validated guidelines, translated into English, and visualized through thematic analysis. RESULTS: Responsible individuals from different levels of the Myanmar National Malaria Control Programme participated in the IDIs. Most of them reported being aware of the markedly increasing trend of P. vivax and the possibility of relapse cases, especially among migrants who are lost to follow-up. Workload was a key concern surrounding intervention implementation. The respondents discussed possible interventions, such as implementing directly observed treatment (DOT) by family members, piloting a shorter PQ regimen, expanding the community's malaria volunteer network, and strengthening health education activities using local languages to promote reasonable drug adherence. FGDs among community members revealed that although people were knowledgeable about malaria symptoms, places to seek treatment, and the use of bed nets to prevent mosquito bites, most of them still preferred to be treated by quack doctors and rarely used insecticide-treated nets at worksites. Many often stopped taking the prescribed drugs once the symptoms disappeared. Nevertheless, some respondents requested more bed nets to be distributed and health promotion activities to be conducted. CONCLUSION: In rural areas where human resources are limited, interventions such as implementing family member DOT or shortening PQ regimens should be introduced to enhance the radical cure for the P. vivax infection. Disseminating information about the importance of taking the entire treatment course and emphasizing the burden of relapse is also essential.


Assuntos
Antimaláricos , Malária Vivax , Malária , Humanos , Primaquina/uso terapêutico , Antimaláricos/uso terapêutico , Malária Vivax/tratamento farmacológico , Malária Vivax/prevenção & controle , Mianmar/epidemiologia , Malária/tratamento farmacológico , Malária/prevenção & controle , Malária/epidemiologia , Recidiva , Adesão à Medicação , Plasmodium vivax
2.
Infection ; 50(3): 681-688, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35034327

RESUMO

BACKGROUND: In the Greater Mekong Subregion of Southeast Asia, Plasmodium vivax malaria is endemic and causes significant morbidity. In this study, the efficacy of chloroquine for treating uncomplicated P. vivax malaria at the eastern and western borders of Myanmar was investigated. METHODS: A total of 197 participants with microscopically confirmed P. vivax infection were enrolled from three townships of the southeastern (Thanbyuzayat and Kawthoung) and western (Kyauktaw) borders of Myanmar. Patients were treated with chloroquine according to the national malaria treatment guidelines and followed for 28 days. RESULTS: Among the 197 enrollments, 172 completed the 28-day follow-up. Twelve recurrent P. vivax infections, all occurring in the third and fourth week, were detected, resulting in an overall cumulative rate of recurrence of 4.7% [95% confidence interval (CI) 1.5-7.8]. The incidence rate of recurrence varied among the three sites. In Thanbyuzayat township, no patients had recurrent parasitemia between days 7 and 28. In contrast, Kyauktaw township had a day 28 cumulative incidence rate of recurrence of 7.2% (95% CI 0.6-13.9%) compared to 6.9% (95% CI 0.6-13.2) in Kawthoung township. CONCLUSION: While this study confirmed the relatively high clinical efficacy of chloroquine for treating P. vivax in Myanmar with modest rates of recurrent infections within 28 days of the treatment, it also revealed considerable geographical heterogeneity of chloroquine efficacy, which warrants continuous surveillance efforts.


Assuntos
Antimaláricos , Malária Vivax , Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Humanos , Malária Vivax/tratamento farmacológico , Malária Vivax/epidemiologia , Mianmar/epidemiologia , Plasmodium vivax
3.
BMC Infect Dis ; 22(1): 653, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902825

RESUMO

BACKGROUND: While national malaria incidence has been declining in Myanmar, some subregions within the nation continue to have high burdens of malaria morbidity and mortality. This study assessed the malaria situation in one of these regions, Banmauk Township, located near the Myanmar-India border. Our goal was to provide a detailed description of the malaria epidemiology in this township and to provide some evidence-based recommendations to formulate a strategy for reaching the national malaria elimination plan. Banmauk consistently has one of the highest malaria burdens in Myanmar. METHODS: With the implementation of strengthened malaria control and surveillance activities after the endorsement of a national malaria elimination plan in 2015, detailed incidence data were obtained for 2016-2018 for Banmauk Township. The data include patient demographics, parasite species, disease severity, and disease outcome. Data were analyzed to identify characteristics, trends, distribution, and risk factors. RESULTS: During 2016-2018, 2,402 malaria cases were reported, with Plasmodium falciparum accounting for 83.4% of infections. Both P. falciparum and P. vivax were transmitted more frequently during the rainy season (May-October). Despite intensified control, the annual parasite incidence rate (API) in 2017 (11.0) almost doubled that in 2016 (6.5). In total, 2.5% (59/2042) of the cases, of which 54 P. falciparum and 5 P. vivax, were complicated cases, resulting in 5 deaths. Malaria morbidity was high in children < 15 years and accounted for 33.4% of all cases and about 47% of the complicated cases. Older age groups and males living with poor transportation conditions were more likely to test positive especially in rainy and cold seasons. Despite the clear seasonality of malaria, severe cases were found among young children even more common in the dry season, when malaria incidence was low. CONCLUSIONS: Despite the declining trend, the malaria burden remained high in Banmauk Township. Our study also documented severe cases and deaths from both falciparum and vivax malaria. P. falciparum remained the predominant parasite species, demanding increased efforts to achieve the goal of elimination of P. falciparum by 2025. As P. falciparum cases decreased, the proportion of cases attributable to P. vivax increased. In order to eliminate malaria, it will likely be important to increasingly target this species as well.


Assuntos
Malária Falciparum , Malária Vivax , Malária , Idoso , Criança , Pré-Escolar , Humanos , Malária/epidemiologia , Malária/parasitologia , Malária/prevenção & controle , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Falciparum/prevenção & controle , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Malária Vivax/prevenção & controle , Masculino , Mianmar/epidemiologia , Plasmodium falciparum , Plasmodium vivax , Fatores de Risco
4.
BMC Infect Dis ; 21(1): 1146, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758727

RESUMO

BACKGROUND: Residual malaria is probably an important source for the re-emergence of malaria infection in the elimination era. Assessment to identify the factors influencing residual malaria in high-risk groups is needed to develop evidence-based decisions by stakeholders and policymakers. METHODS: This study was conducted to explore the factors influencing the residual malaria infection among migrant workers in two sentinel sites (endemic vs. pre-elimination areas) in Myanmar using the mixed-model method. RESULTS: A total of 102 migrant respondents (65 in Bamauk and 37 in Shwegyin) were included for the quantitative assessment using pretested questionnaires during household visits. Although 87.3% of them had insecticidal bed nets (ITNs/LLINs), only 68.3% of the migrants in Bamauk and 57.9% in Shwegyin used it regularly. The use of any bed net was high (79.9% in Bamauk vs. 91.0% in Shwegyin). The mean LLINs in their families were 1.64 (95%CI: 1.48-1.81) in Bamauk and 2.89 (95%CI: 2.67-3.11) in Shwegyin. Most of them received no health information for malaria prevention within the last year and their knowledge about malaria was low. Their working nature was a challenge for control measures against malaria in migrants. CONCLUSION: The strategy for distributing LLINs and health promotion activities for mobile/migrant populations should be reviewed, and an appropriate action plan should be developed for the specific migrant group. Moreover, health promotion activities for behavior change communication should be strengthened in the migrant population in Myanmar.


Assuntos
Mosquiteiros Tratados com Inseticida , Malária , Migrantes , Características da Família , Humanos , Malária/epidemiologia , Malária/prevenção & controle , Mianmar/epidemiologia
5.
Malar J ; 19(1): 304, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854686

RESUMO

BACKGROUND: Currently, artemisinin-based combination therapy (ACT) is the first-line anti-malarial treatment in malaria-endemic areas. However, resistance in Plasmodium falciparum to artemisinin-based combinations emerging in the Greater Mekong Sub-region is a major problem hindering malaria elimination. To continuously monitor the potential spread of ACT-resistant parasites, this study assessed the efficacy of artemether-lumefantrine (AL) for falciparum malaria in western Myanmar. METHODS: Ninety-five patients with malaria symptoms from Paletwa Township, Chin State, Myanmar were screened for P. falciparum infections in 2015. After excluding six patients with a parasite density below 100 or over 150,000/µL, 41 P. falciparum patients were treated with AL and followed for 28 days. Molecular markers associated with resistance to 4-amino-quinoline drugs (pfcrt and pfmdr1), antifolate drugs (pfdhps and pfdhfr) and artemisinin (pfk13) were genotyped to determine the prevalence of mutations associated with anti-malarial drug resistance. RESULTS: For the 41 P. falciparum patients (27 children and 14 adults), the 28-day AL therapeutic efficacy was 100%, but five cases (12.2%) were parasite positive on day 3 by microscopy. For the pfk13 gene, the frequency of NN insert after the position 136 was 100% in the day-3 parasite-positive group as compared to 50.0% in the day-3 parasite-negative group, albeit the difference was not statistically significant (P = 0.113). The pfk13 K189T mutation (10.0%) was found in Myanmar for the first time. The pfcrt K76T and A220S mutations were all fixed in the parasite population. In pfmdr1, the Y184F mutation was present in 23.3% of the parasite population, and found in both day-3 parasite-positive and -negative parasites. The G968A mutation of pfmdr1 gene was first reported in Myanmar. Prevalence of all the mutations in pfdhfr and pfdhps genes assessed was over 70%, with the exception of the pfdhps A581G mutation, which was 3.3%. CONCLUSIONS: AL remained highly efficacious in western Myanmar. Pfk13 mutations associated with artemisinin resistance were not found. The high prevalence of mutations in pfcrt, pfdhfr and pfdhps suggests high-degree resistance to chloroquine and antifolate drugs. The pfmdr1 N86/184F/D1246 haplotype associated with selection by AL in Africa reached > 20% in this study. The detection of > 10% patients who were day-3 parasite-positive after AL treatment emphasizes the necessity of continuously monitoring ACT efficacy in western Myanmar.


Assuntos
Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Resistência a Medicamentos/genética , Plasmodium falciparum/genética , Adolescente , Adulto , Criança , Feminino , Humanos , Malária Falciparum/prevenção & controle , Masculino , Pessoa de Meia-Idade , Mianmar , Plasmodium falciparum/efeitos dos fármacos , Adulto Jovem
6.
Malar J ; 19(1): 281, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758218

RESUMO

BACKGROUND: In the Greater Mekong sub-region, Plasmodium vivax has become the predominant species and imposes a major challenge for regional malaria elimination. This study aimed to investigate the variations in genes potentially related to drug resistance in P. vivax populations from the China-Myanmar border area. In addition, this study also wanted to determine whether divergence existed between parasite populations associated with asymptomatic and acute infections. METHODS: A total of 66 P. vivax isolates were obtained from patients with acute malaria who attended clinics at the Laiza area, Kachin State, Myanmar in 2015. In addition, 102 P. vivax isolates associated with asymptomatic infections were identified by screening of volunteers without signs or symptoms from surrounding villages. Slide-positive samples were verified with nested PCR detecting the 18S rRNA gene. Multiclonal infections were further excluded by genotyping at msp-3α and msp-3ß genes. Parasite DNA from 60 symptomatic cases and 81 asymptomatic infections was used to amplify and sequence genes potentially associated with drug resistance, including pvmdr1, pvcrt-o, pvdhfr, pvdhps, and pvk12. RESULTS: The pvmdr1 Y976F and F1076L mutations were present in 3/113 (2.7%) and 97/113 (85.5%) P. vivax isolates, respectively. The K10 insertion in pvcrt-o gene was found in 28.2% of the parasites. Four mutations in the two antifolate resistance genes reached relatively high levels of prevalence: pvdhfr S58R (53.4%), S117N/T (50.8%), pvdhps A383G (75.0%), and A553G (36.3%). Haplotypes with wild-type pvmdr1 (976Y/997K/1076F) and quadruple mutations in pvdhfr (13I/57L/58R/61M/99H/117T/173I) were significantly more prevalent in symptomatic than asymptomatic infections, whereas the pvmdr1 mutant haplotype 976Y/997K/1076L was significantly more prevalent in asymptomatic than symptomatic infections. In addition, quadruple mutations at codons 57, 58, 61 and 117 of pvdhfr and double mutations at codons 383 and 553 of pvdhps were found both in asymptomatic and symptomatic infections with similar frequencies. No mutations were found in the pvk12 gene. CONCLUSIONS: Mutations in pvdhfr and pvdhps were prevalent in both symptomatic and asymptomatic P. vivax infections, suggestive of resistance to antifolate drugs. Asymptomatic carriers may act as a silent reservoir sustaining drug-resistant parasite transmission necessitating a rational strategy for malaria elimination in this region.


Assuntos
Antimaláricos/administração & dosagem , Resistência a Medicamentos/genética , Marcadores Genéticos , Malária Vivax/parasitologia , Plasmodium vivax/genética , Proteínas de Protozoários/genética , Adolescente , Adulto , Infecções Assintomáticas , Criança , Feminino , Humanos , Masculino , Proteínas de Membrana Transportadoras/análise , Proteínas Associadas à Resistência a Múltiplos Medicamentos/análise , Mianmar , Plasmodium vivax/efeitos dos fármacos , Proteínas de Protozoários/análise , Análise de Sequência de DNA , Adulto Jovem
7.
BMC Infect Dis ; 20(1): 906, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256616

RESUMO

BACKGROUNDS: Primary infection with Toxoplasma gondii during pregnancy can pose serious health problems for the fetus. However, the epidemiological status of toxoplasmosis among reproductive-aged population in Myanmar is largely unknown. Although luciferase immunoprecipitation system (LIPS) assays for serodiagnosis of toxoplasmosis was developed mostly using mouse infection model, had not been tested by using field-derived human samples. METHODS: A total of 251 serum samples were collected from reproductive-aged women, residing in Shwegyin township, Bago region, Myanmar and analyzed with a commercial ELISA kit, as well as in-house LIPS assays. RESULTS: The overall seroprevalence for Toxoplasma gondii infection by the commercial ELISA was 11.5%. No clear risk factor was identified except for being in the younger age group (15-30 years old). Overall, LIPS assays showed low sensitivity when the commercial ELSA was used as a reference test. CONCLUSION: We identified the epidemiological situation of toxoplasmosis in some rural communities in Myanmar. The data obtained here will serve as a primary information for the effort to reduce toxoplasmosis in this region. Although looked promising in the previous experiments with mouse infection model, we found that the reported LIPS procedures need further improvements to increase the sensitivities.


Assuntos
Imunoprecipitação/métodos , Medições Luminescentes/métodos , Testes Sorológicos/métodos , Toxoplasma/imunologia , Toxoplasmose/diagnóstico , Toxoplasmose/epidemiologia , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Luciferases , Substâncias Luminescentes , Camundongos , Pessoa de Meia-Idade , Mianmar/epidemiologia , Fatores de Risco , População Rural , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Toxoplasmose/sangue , Toxoplasmose/parasitologia , Adulto Jovem
8.
Malar J ; 18(1): 362, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718628

RESUMO

BACKGROUND: Interventions to raise community awareness about malaria prevention and treatment have used various approaches with little evidence on their efficacy. This study aimed to determine the effectiveness of loudspeaker announcements regarding malaria care and prevention practices among people living in the malaria endemic villages of Banmauk Township, Sagaing Region, Myanmar. METHODS: Four villages among the most malaria-burdened areas were randomly selected: two villages were assigned as the intervention group, and two as the control. Prior to the peak transmission season of malaria in June 2018, a baseline questionnaire was administered to 270 participants from randomly selected households in the control and intervention villages. The loudspeaker announcements broadcasted health messages on malaria care and prevention practices regularly at 7:00 pm every other day. The same questionnaire was administered at 6-month post intervention to both groups. Descriptive statistics, Chi-square, and the t-test were utilized to assess differences between and within groups. RESULTS: Participants across the control and intervention groups showed similar socio-economic characteristics; the baseline knowledge, attitude and practice mean scores were not significantly different between the groups. Six months after the intervention, improvements in scores were observed at p-value < 0.001 in both groups, however; the increase was greater among the intervention group. The declining trend of malaria was also noticed during the study period. In addition, more than 75% of people expressed positive opinions of the intervention. CONCLUSIONS: The loudspeaker intervention was found to be feasible and effective, as shown by the significant improvement in scores related to prevention and care-seeking practices for malaria as well as reduced malaria morbidity. Expanding the intervention to a larger population in this endemic region and evaluating its long-term effectiveness are essential in addition to replicating this in other low-resource malaria endemic regions.


Assuntos
Educação em Saúde/métodos , Malária/prevenção & controle , Meios de Comunicação de Massa , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , População Rural/estatística & dados numéricos , Adulto , Idoso , Doenças Endêmicas/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mianmar , Adulto Jovem
9.
Malar J ; 18(1): 309, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31514740

RESUMO

BACKGROUND: Intensive malaria transmission along international borders is a significant impediment to malaria elimination in the Greater Mekong Subregion (GMS) of Southeast Asia. Passive case detection (PCD) was used to study the dynamics and trends of malaria transmission at the China-Myanmar border to provide epidemiologic information for improved malaria control. METHODS: PCD was conducted in one hospital and 12 clinics near the Laiza town in northeast Myanmar from 2011 to 2016. Clinical malaria was diagnosed by microscopy and demographic information was captured using a structured questionnaire at the time of the patient's presentation for care. RESULTS: Over the study period, 6175 (19.7%) malaria cases were confirmed by microscopy from 31,326 suspected cases. The four human malaria parasite species were all identified, with Plasmodium vivax and Plasmodium falciparum accounting for 5607 (90.8%) and 481 (7.8%) of the confirmed cases, respectively. In contrast to the steady decline of malaria in the general GMS, the study site had an upward trend of malaria incidence with vivax malaria outbreaks in 2013 and 2016. Adult males, children under the age of 15, and those with occupations such as farming, being a soldier or student, had significantly higher risks of clinical malaria compared to having fevers from other aetiologies. A self-reported history of clinical malaria was also associated with a higher risk of confirmed malaria. CONCLUSIONS: The China-Myanmar border area has experienced an overall upward trend of malaria incidence in recent years with P. vivax becoming the predominant species. Evidence-based control strategies need to focus on high-risk populations.


Assuntos
Malária/epidemiologia , Plasmodium/isolamento & purificação , Fatores Socioeconômicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Malária/diagnóstico , Masculino , Pessoa de Meia-Idade , Mianmar/epidemiologia , Plasmodium/classificação , Adulto Jovem
10.
Malar J ; 17(1): 6, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29304809

RESUMO

BACKGROUND: As the prevalence of the malaria has been decreasing in many endemic countries including Myanmar, malaria elimination in Greater Mekong Region was targeted not later than 2030. The relevance of molecular and serological tools to identify residual transmission remains to be established in this setting. METHODS: One-year cohort study was conducted and sera samples were collected in every 3 months with active and passive case detection for clinical malaria episodes by RDT, microscopy and molecular method. The sera were used to detect the malaria antibody against PfMSP1-19, PvAMA1, PvDBPII and PvMSP1-19 by protein microarray. RESULTS: Among the recruited 1182 participants, there was no RDT positive case for malaria infection although two vivax infections were detected by microscopy in initial collection. Molecular methods detected the asymptomatic cases of 28/1182 (2.37%) in first, 5/894 (0.42%) in second, 12/944 (1.02%) in third, 6/889 (0.51%) in fourth collection, respectively. Seropositivity rates against the PfMSP1-19, PvMSP1-19, PvAMA1 and PvDBPII were 73/270 (27.0%), 85/270 (31.5%), 65/270 (24.1%) and 160/270 (59.3%), respectively. PfMSP1-19 and PvMSP1-19 showed high and stable antigenicity in acute and subacute samples but declining in 1-year history samples. No cross reactivity of PfMSP1-19 and PvMSP1-19 between the two species and higher seropositivity among the asymptomatic carriers were observed. Mapping data indicated serological surveillance can detect the geographical pattern of malaria infection under low transmission setting. CONCLUSIONS: These findings support that PfMSP1-19 and PvMSP1-19 are suggested for serosurveillance of the malaria especially in low transmission setting for further necessary actions have to be carried out to eliminate the malaria.


Assuntos
Anticorpos Antiprotozoários/sangue , Transmissão de Doença Infecciosa , Malária/epidemiologia , Malária/transmissão , Testes Sorológicos/métodos , Adolescente , Adulto , Portador Sadio/epidemiologia , Portador Sadio/transmissão , Cromatografia de Afinidade , Estudos de Coortes , Monitoramento Epidemiológico , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Análise em Microsséries , Microscopia , Pessoa de Meia-Idade , Mianmar/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Análise Serial de Proteínas , Adulto Jovem
11.
Emerg Infect Dis ; 23(3): 517-520, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28221121

RESUMO

Artemisinin resistance containment in Myanmar was initiated in 2011 after artemisinin-resistant Plasmodium falciparum malaria was reported. Molecular evidence suggests that asymptomatic malaria infections harboring drug resistance genes are present among residents of the Myanmar artemisinin resistance containment zone. This evidence supports efforts to eliminate these hidden infections.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Malária/epidemiologia , Malária/parasitologia , Plasmodium/efeitos dos fármacos , Adolescente , Adulto , Resistência a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Mianmar , Adulto Jovem
12.
Malar J ; 16(1): 117, 2017 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28298235

RESUMO

BACKGROUND: One of the major challenges for control and elimination of malaria is ongoing spread and emergence of drug resistance. While epidemiology and surveillance of the drug resistance in falciparum malaria is being explored globally, there are few studies on drug resistance vivax malaria. METHODS: To assess the spread of drug-resistant vivax malaria in Myanmar, a multisite, prospective, longitudinal study with retrospective analysis of previous therapeutic efficacy studies, was conducted. A total of 906 from nine study sites were included in retrospective analysis and 208 from three study sites in prospective study. Uncomplicated vivax mono-infected patients were recruited and monitored with longitudinal follow-up until day 28 after treatment with chloroquine. Amplification and sequence analysis of molecular markers, such as mutations in pvcrt-O, pvmdr1, pvdhps and pvdhfr, were done in day-0 samples in prospective study. RESULTS: Clinical failure cases were found only in Kawthaung, southern Myanmar and western Myanmar sites within 2009-2016. Chloroquine resistance markers, pvcrt-O 'AAG' insertion and pvmdr1 mutation (Y976F) showed higher mutant rate in southern and central Myanmar than western site: 66.7, 72.7 vs 48.3% and 26.7, 17.0 vs 1.7%, respectively. A similar pattern of significantly higher mutant rate of antifolate resistance markers, pvdhps (S382A, K512M, A553G) and pvdhfr (F57L/I, S58R, T61M, S117T/N) were noted. CONCLUSIONS: Although clinical failure rate was low, widespread distribution of chloroquine and antifolate resistance molecular makers alert to the emergence and spread of drug resistance vivax malaria in Myanmar. Proper strategy and action plan to eliminate and contain the resistant strain strengthened together with clinical and molecular surveillance on drug resistance vivax is recommended.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Resistência a Medicamentos , Antagonistas do Ácido Fólico/farmacologia , Plasmodium vivax/efeitos dos fármacos , Adolescente , Adulto , Resistência a Medicamentos/genética , Genes de Protozoários/genética , Humanos , Estudos Longitudinais , Malária Vivax/tratamento farmacológico , Malária Vivax/parasitologia , Mutação , Mianmar , Plasmodium vivax/genética , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
13.
Malar J ; 16(1): 281, 2017 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-28693552

RESUMO

BACKGROUND: Plasmodium vivax malaria remains a major public health burden in Myanmar. Resistance to chloroquine (CQ), the first-line treatment for P. vivax, has been reported in the country and has potential to undermine local control efforts. METHODS: Patients over 6 years of age with uncomplicated P. vivax mono-infection were enrolled into clinical efficacy studies in Myawaddy in 2014 and Kawthoung in 2012. Study participants received a standard dose of CQ (25 mg/kg over 3 days) followed by weekly review until day 28. Pvmdr1 copy number (CN) and microsatellite diversity were assessed on samples from the patients enrolled in the clinical study and additional cross-sectional surveys undertaken in Myawaddy and Shwegyin in 2012. RESULTS: A total of 85 patients were enrolled in the CQ clinical studies, 25 in Myawaddy and 60 in Kawthoung. One patient in Myawaddy (1.2%) had an early treatment failure and two patients (2.3%) in Kawthoung presented with late treatment failures on day 28. The day 28 efficacy was 92.0% (95% CI 71.6-97.9) in Myawaddy and 98.3% (95% CI 88.7-99.8) in Kawthoung. By day 2, 92.2% (23/25) in Myawaddy and 85.0% (51/60) in Kawthoung were aparasitaemic. Genotyping and pvmdr1 CN assessment was undertaken on 43, 52 and 46 clinical isolates from Myawaddy, Kawthoung and Shwegyin respectively. Pvmdr1 amplification was observed in 3.2% (1/31) of isolates in Myawaddy, 0% (0/49) in Kawthoung and 2.5% (1/40) in Shwegyin. Diversity was high in all sites (H E 0.855-0.876), with low inter-population differentiation (F ST 0.016-0.026, P < 0.05). CONCLUSIONS: Treatment failures after chloroquine were observed following chloroquine monotherapy, with pvmdr1 amplification present in both Myawaddy and Shwegyin. The results emphasize the importance of ongoing P. vivax drug resistance surveillance in Myanmar, particularly given the potential connectivity between parasite population at different sites.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Fluxo Gênico , Variação Genética , Malária Vivax/tratamento farmacológico , Plasmodium vivax/efeitos dos fármacos , Plasmodium vivax/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos Transversais , Variações do Número de Cópias de DNA , Feminino , Genótipo , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Mianmar , Proteínas de Protozoários/genética , Adulto Jovem
14.
Malar J ; 16(1): 333, 2017 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-28806957

RESUMO

BACKGROUND: Emergence of artemisinin-resistant malaria in Southeast Asian countries threatens the global control of malaria. Although K13 kelch propeller has been assessed for artemisinin resistance molecular marker, most of the mutations need to be validated. In this study, artemisinin resistance was assessed by clinical and molecular analysis, including k13 and recently reported markers, pfarps10, pffd and pfmdr2. METHODS: A prospective cohort study in 1160 uncomplicated falciparum patients was conducted after treatment with artemisinin-based combination therapy (ACT), in 6 sentinel sites in Myanmar from 2009 to 2013. Therapeutic efficacy of ACT was assessed by longitudinal follow ups. Molecular markers analysis was done on all available day 0 samples. RESULTS: True recrudescence treatment failures cases and day 3 parasite positivity were detected at only the southern Myanmar sites. Day 3 positive and k13 mutants with higher prevalence of underlying genetic foci predisposing to become k13 mutant were detected only in southern Myanmar since 2009 and comparatively fewer mutations of pfarps10, pffd, and pfmdr2 were observed in western Myanmar. K13 mutations, V127M of pfarps10, D193Y of pffd, and T448I of pfmdr2 were significantly associated with day 3 positivity (OR: 6.48, 3.88, 2.88, and 2.52, respectively). CONCLUSIONS: Apart from k13, pfarps10, pffd and pfmdr2 are also useful for molecular surveillance of artemisinin resistance especially where k13 mutation has not been reported. Appropriate action to eliminate the resistant parasites and surveillance on artemisinin resistance should be strengthened in Myanmar. Trial registration This study was registered with ClinicalTrials.gov, identifier NCT02792816.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/genética , Biomarcadores , Mianmar , Plasmodium falciparum/genética , Proteínas de Protozoários/metabolismo
16.
Malar J ; 15: 308, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27267877

RESUMO

BACKGROUND: After artemisinin resistance was reported, the Myanmar artemisinin resistance containment (MARC) project was initiated in 2011. One of the activities of MARC is to train volunteers for early diagnosis and prompt treatment by providing rapid diagnostic tests (RDT) and artemisinin combination therapy. This study aimed to fulfil the gap of information on the challenges faced by malaria volunteers in artemisinin-containment areas. METHODS: A cross-sectional, descriptive study was conducted in 11 townships in MARC areas to assess the challenges in early diagnosis of malaria and treatment by malaria volunteers using qualitative and quantitative approaches. RESULTS: Altogether 405 volunteers participated in the study. Although 97.5 % of volunteers can interpret a positive result for malaria, only 41.2 % correctly stated the persistence of a positive result in recently infected cases. Over 80 % knew the effects of temperature and humidity on performance of the malaria RDT. Unexpectedly, 15.1 % perceived that expired RDTs can still be useful for diagnosis although 98.3 % of respondents cited that the overall results of RDTs were reliable. Although most of them knew the treatment for malaria based on RDT results, some could not give the correct answer, while a few (2 %) mentioned artesunate monotherapy for RDT-negative cases. Training received by volunteers was also varied in study sites and 92.1 % believed that it was not sufficient. A certain portion of them faced the problem of regular supply of RDTs (9.9 %) and drugs (47.5 %), interpretation of result of RDTs (30 %), and performing blood test (20 %). The median RDT tested per month (25th, 75th percentile) was 6.0 (2.0, 15.0) indicating the need for prioritization based on endemicity. Regular reporting, supervision, monitoring system, and proper refresher training using uniform content of guideline to correct misconception of the volunteers, were needed to be strengthened. Moreover, the reliable and regular supply of materials and exchange system for expired RDTs and anti-malarials was important in the effectiveness of volunteers in MARC zones. CONCLUSIONS: Adequate refresher training, monitoring, supervision, and regular reliable supply of RDTs and anti-malarials were needed for capacity strengthening of volunteers in MARC zones.


Assuntos
Antimaláricos/administração & dosagem , Antimaláricos/farmacologia , Artemisininas/administração & dosagem , Artemisininas/farmacologia , Resistência a Medicamentos , Malária/diagnóstico , Malária/tratamento farmacológico , Atitude do Pessoal de Saúde , Agentes Comunitários de Saúde , Estudos Transversais , Quimioterapia Combinada/métodos , Diagnóstico Precoce , Educação Médica , Conhecimentos, Atitudes e Prática em Saúde , Voluntários Saudáveis , Humanos , Mianmar , Prevenção Secundária
17.
Malar J ; 15: 41, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26809885

RESUMO

BACKGROUND: Myanmar has the highest malaria incidence and attributed mortality in South East Asia with limited healthcare infrastructure to manage this burden. Establishing malaria Community Health Worker (CHW) programmes is one possible strategy to improve access to malaria diagnosis and treatment, particularly in remote areas. Despite considerable donor support for implementing CHW programmes in Myanmar, the cost implications are not well understood. METHODS: An ingredients based micro-costing approach was used to develop a model of the annual implementation cost of malaria CHWs in Myanmar. A cost model was constructed based on activity centres comprising of training, patient malaria services, monitoring and supervision, programme management, overheads and incentives. The model takes a provider perspective. Financial data on CHWs programmes were obtained from the 2013 financial reports of the Three Millennium Development Goal fund implementing partners that have been working on malaria control and elimination in Myanmar. Sensitivity and scenario analyses were undertaken to outline parameter uncertainty and explore changes to programme cost for key assumptions. RESULTS: The range of total annual costs for the support of one CHW was US$ 966-2486. The largest driver of CHW cost was monitoring and supervision (31-60% of annual CHW cost). Other important determinants of cost included programme management (15-28% of annual CHW cost) and patient services (6-12% of annual CHW cost). Within patient services, malaria rapid diagnostic tests are the major contributor to cost (64% of patient service costs). CONCLUSION: The annual cost of a malaria CHW in Myanmar varies considerably depending on the context and the design of the programme, in particular remoteness and the approach to monitoring and evaluation. The estimates provide information to policy makers and CHW programme planners in Myanmar as well as supporting economic evaluations of their cost-effectiveness.


Assuntos
Agentes Comunitários de Saúde/economia , Serviços de Saúde Comunitária/economia , Humanos , Mianmar
18.
Malar J ; 15(1): 503, 2016 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-27756394

RESUMO

BACKGROUND: There has been an impressive recent reduction in the global incidence of malaria, but the development of artemisinin resistance in the Greater Mekong Region threatens this progress. Increasing artemisinin resistance is particularly important in Myanmar, as it is the country in the Greater Mekong Region with the greatest malaria burden. If malaria is to be eliminated in the region, it is essential to define the spatial and temporal epidemiology of the disease in Myanmar to inform control strategies optimally. RESULTS: Between the years 2005 and 2014 there was an 81.1 % decline in the reported annual incidence of malaria in Myanmar (1341.8 cases per 100,000 population to 253.3 cases per 100,000 population). In the same period, there was a 93.5 % decline in reported annual mortality from malaria (3.79 deaths per 100,000 population to 0.25 deaths per 100,000 population) and a 87.2 % decline in the proportion of hospitalizations due to malaria (7.8 to 1.0 %). Chin State had the highest reported malaria incidence and mortality at the end of the study period, although socio-economic and geographical factors appear a more likely explanation for this finding than artemisinin resistance. The reduced malaria burden coincided with significant upscaling of disease control measures by the national government with support from international partners. These programmes included the training and deployment of over 40,000 community health care workers, the coverage of over 60 % of the at-risk population with insecticide-treated bed nets and significant efforts to improve access to artemesinin-based combination treatment. Beyond these malaria-specific programmes, increased general investment in the health sector, changing population demographics and deforestation are also likely to have contributed to the decline in malaria incidence seen over this time. CONCLUSIONS: There has been a dramatic fall in the burden of malaria in Myanmar since 2005. However, with the rise of artemisinin resistance, continued political, financial and scientific commitment is required if the ambitious goal of malaria elimination in the country is to be realized.


Assuntos
Malária/epidemiologia , Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos , Humanos , Incidência , Lactonas/farmacologia , Malária/mortalidade , Mianmar/epidemiologia , Plasmodium/efeitos dos fármacos , Análise de Sobrevida
19.
Anal Bioanal Chem ; 408(22): 6003-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26873200

RESUMO

Artesunate is a frontline antimalarial drug for treating Plasmodium falciparum malaria. To produce specific antibodies to artesunate, the carboxyl group of artesunate was directly conjugated to carrier protein as the immunogen. A specific monoclonal antibody (mAb) 3D82G6 against artesunate was obtained by high-throughput screening of positive hybridoma clones. This monoclonal antibody had 4.0, 0.5, and 0.9 % cross reactivities with artemisinin, dihydroartemisinin, and artemether, respectively. A dipstick immunoassay was developed, and the indicator range for artesunate was 1000-2000 ng mL(-1). No interference was observed with artemisinin, dihydroartemisinin, artemether, and other commonly used antimalarial drugs for up to 20,000 ng mL(-1). The dipsticks were used for determination of artesunate contents in commercial drugs, and the results were agreeable with those determined by high-performance liquid chromatography. This dipstick, with its specificity and sensitivity for artesunate and simplicity to use, makes it a potential point-of-care device for rapid quality evaluation of artesunate-containing antimalarial drugs. Graphical Abstract Specific monoclonal antibody-based lateral flow dipstick for artesunate.


Assuntos
Anticorpos Imobilizados/química , Anticorpos Monoclonais/química , Antimaláricos/análise , Artemisininas/análise , Imunoensaio/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Animais , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/imunologia , Antimaláricos/imunologia , Artemisininas/imunologia , Artesunato , Coloide de Ouro/química , Humanos , Hibridomas , Limite de Detecção , Malária Falciparum/tratamento farmacológico , Camundongos , Fitas Reagentes/análise
20.
Korean J Parasitol ; 54(3): 253-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27417078

RESUMO

In the era of (pre) elimination setting, the prevalence of malaria has been decreasing in most of the previously endemic areas. Therefore, effective cost- and time-saving validated pooling strategy is needed for detection of malaria in low transmission settings. In this study, optimal pooling numbers and lowest detection limit were assessed using known density samples prepared systematically, followed by genomic DNA extraction and nested PCR. Pooling strategy that composed of 10 samples in 1 pool, 20 µl in 1 sample, was optimal, and the parasite density as low as 2 p/µl for both falciparum and vivax infection was enough for detection of malaria. This pooling method showed effectiveness for handling of a huge number of samples in low transmission settings (<9% positive rate). The results indicated that pooling of the blood samples before DNA extraction followed by usual nested PCR is useful and effective for detection of malaria in screening of hidden cases in low-transmission settings.


Assuntos
Sangue/parasitologia , DNA de Protozoário/análise , Malária/diagnóstico , Programas de Rastreamento/métodos , Parasitologia/métodos , Plasmodium/isolamento & purificação , Manejo de Espécimes/métodos , DNA de Protozoário/genética , Humanos , Técnicas de Diagnóstico Molecular/métodos , Plasmodium/genética , Reação em Cadeia da Polimerase/métodos
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