RESUMO
BACKGROUND: Southeast Asia is undergoing an epidemiological transition with non-communicable illnesses becoming increasingly important, yet infectious diseases (tuberculosis, HIV, hepatitis B, malaria) remain widely prevalent in some populations, while emerging and zoonotic diseases threaten. There are also limited population-level estimates of many important heath conditions. This restricts evidence-based decision-making for disease control and prevention priorities. Cross-sectional surveys can be efficient epidemiological tools to measure the prevalence of a wide range of diseases, but no systematic assessment of their coverage of different health conditions has been produced for the region. METHODS: We conducted a systematic search in Medline, Embase, Global Health, CINAHL, Scopus, Web of Science Core Collection, and Global Index Medicus, and additionally Google Scholar. Our inclusion criteria were cross-sectional surveys conducted with community-based recruitment, in Bangladesh, Cambodia, Laos, Myanmar, and Thailand, published between January 1, 2010 and January 27, 2021, and reporting the prevalence of any health condition. RESULTS: 542 publications from 337 surveys were included. Non-communicable conditions (n = 205) were reported by more surveys than infectious conditions (n = 124). Disability (n = 49), self-report history of any disease or symptoms (n = 35), and self-perceived health status (n = 34), which reflect a holistic picture of health, were studied by many fewer surveys. In addition, 45 surveys studied symptomatic conditions which overlap between non-communicable and infectious conditions. The most surveyed conditions were undernutrition, obesity, hypertension, diabetes, intestinal parasites, malaria, anemia, diarrhea, fever, and acute respiratory infections. These conditions overlap with the most important causes of death and disability in the Global Burden of Disease study. However, other high-burden conditions (e.g. hearing loss, headache disorder, low back pain, chronic liver and kidney diseases, and cancers) were rarely studied. CONCLUSION: There were relatively few recent surveys from which to estimate representative prevalences and trends of health conditions beyond those known to be high burden. Expanding the spectrum of health conditions in cross-sectional surveys could improve understanding of evolving disease patterns in the region.
Assuntos
Doenças não Transmissíveis , Humanos , Sudeste Asiático/epidemiologia , Doenças Transmissíveis/epidemiologia , Estudos Transversais , Nível de Saúde , Inquéritos Epidemiológicos , Doenças não Transmissíveis/epidemiologia , PrevalênciaRESUMO
BACKGROUND: Malaria in the eastern Greater Mekong subregion has declined to historic lows. Countries in the Greater Mekong subregion are accelerating malaria elimination in the context of increasing antimalarial drug resistance. Infections are now increasingly concentrated in remote, forested foci. No intervention has yet shown satisfactory efficacy against forest-acquired malaria. The aim of this study was to assess the efficacy of malaria chemoprophylaxis among forest goers in Cambodia. METHODS: We conducted an open-label, individually randomised controlled trial in Cambodia, which recruited participants aged 16-65 years staying overnight in forests. Participants were randomly allocated 1:1 to antimalarial chemoprophylaxis, a 3-day course of twice-daily artemether-lumefantrine followed by the same daily dosing once a week while travelling in the forest and for a further 4 weeks after leaving the forest (four tablets per dose; 20 mg of artemether and 120 mg of lumefantrine per tablet), or a multivitamin with no antimalarial activity. Allocations were done according to a computer-generated randomisation schedule, and randomisation was in permuted blocks of size ten and stratified by village. Investigators and participants were not masked to drug allocation, but laboratory investigations were done without knowledge of allocation. The primary outcome was a composite endpoint of either clinical malaria with any Plasmodium species within 1-28, 29-56, or 57-84 days, or subclinical infection detected by PCR on days 28, 56, or 84 using complete-case analysis of the intention-to-treat population. Adherence to study drug was assessed primarily by self-reporting during follow-up visits. Adverse events were assessed in the intention-to-treat population as a secondary endpoint from self-reporting at any time, plus a physical examination and symptom questionnaire at follow-up. This trial is registered at ClinicalTrials.gov (NCT04041973) and is complete. FINDINGS: Between March 11 and Nov 20, 2020, 1480 individuals were enrolled, of whom 738 were randomly assigned to artemether-lumefantrine and 742 to the multivitamin. 713 participants in the artemether-lumefantrine group and 714 in the multivitamin group had a PCR result or confirmed clinical malaria by rapid diagnostic test during follow-up. During follow-up, 19 (3%, 95% CI 2-4) of 713 participants had parasitaemia or clinical malaria in the artemether-lumefantrine group and 123 (17%, 15-20) of 714 in the multivitamin group (absolute risk difference 15%, 95% CI 12-18; p<0·0001). During follow-up, there were 166 malaria episodes caused by Plasmodium vivax, 14 by Plasmodium falciparum, and five with other or mixed species infections. The numbers of participants with P vivax were 18 (3%, 95% CI 2-4) in the artemether-lumefantrine group versus 112 (16%, 13-19) in the multivitamin group (absolute risk difference 13%, 95% CI 10-16; p<0·0001). The numbers of participants with P falciparum were two (0·3%, 95% CI 0·03-1·01) in the artemether-lumefantrine group versus 12 (1·7%, 0·9-2·9) in the multivitamin group (absolute risk difference 1·4%, 95% CI 0·4-2·4; p=0·013). Overall reported adherence to the full course of medication was 97% (95% CI 96-98; 1797 completed courses out of 1854 courses started) in the artemether-lumefantrine group and 98% (97-98; 1842 completed courses in 1885 courses started) in the multivitamin group. Overall prevalence of adverse events was 1·9% (355 events in 18 806 doses) in the artemether-lumefantrine group and 1·1% (207 events in 19 132 doses) in the multivitamin group (p<0·0001). INTERPRETATION: Antimalarial chemoprophylaxis with artemether-lumefantrine was acceptable and well tolerated and substantially reduced the risk of malaria. Malaria chemoprophylaxis among high-risk groups such as forest workers could be a valuable tool for accelerating elimination in the Greater Mekong subregion. FUNDING: The Global Fund to Fight AIDS, Tuberculosis and Malaria; Wellcome Trust.
Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Humanos , Antimaláricos/efeitos adversos , Artemeter/uso terapêutico , Artemisininas/uso terapêutico , Fluorenos/uso terapêutico , Etanolaminas/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Lumefantrina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/prevenção & controle , Malária Falciparum/complicações , Malária/tratamento farmacológico , Malária/prevenção & controle , Camboja/epidemiologia , Quimioprevenção , Combinação de MedicamentosRESUMO
BACKGROUND: In the Greater Mekong Subregion, adults are at highest risk for malaria, particularly those who visit forests. The absence of effective vector control strategies and limited periods of exposure during forest visits suggest that chemoprophylaxis could be an appropriate strategy to protect forest goers against malaria. METHODS: Alongside a clinical trial of anti-malarial chemoprophylaxis in northern Cambodia, qualitative research was conducted, including in-depth interviews and observation, to explore the acceptability of malaria prophylaxis for forest goers, the implementation opportunities, and challenges of this strategy. RESULTS: Prophylaxis with artemether-lumefantrine for forest goers was found to be acceptable under trial conditions. Three factors played a major role: the community's awareness and perception of the effectiveness of prophylaxis, their trust in the provider, and malaria as a local health concern. The findings highlight how uptake and adherence to prophylaxis are influenced by the perceived balance between benefits and burden of anti-malarials which are modulated by the seasonality of forest visits and its influence on malaria risk. CONCLUSIONS: The implementation of anti-malarial prophylaxis needs to consider how the preventive medication can be incorporated into existing vector-control measures, malaria testing and treatment services. The next step in the roll out of anti-malarial prophylaxis for forest visitors will require support from local health workers.
Assuntos
Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Quimioprevenção/estatística & dados numéricos , Malária/prevenção & controle , Adolescente , Adulto , Camboja , Estudos de Viabilidade , Feminino , Florestas , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Cambodia targets malaria elimination by 2025. Rapid elimination will depend on successfully identifying and clearing malaria foci linked to forests. Expanding and maintaining universal access to early diagnosis and effective treatment remains the key to malaria control and ultimately malaria elimination in the Greater Mekong Subregion (GMS) in the foreseeable future. Mass Drug Administration (MDA) holds some promise in the rapid reduction of Plasmodium falciparum infections, but requires considerable investment of resources and time to mobilize the target communities. Furthermore, the most practical drug regimen for MDA in the GMS-three rounds of DHA/piperaquine-has lost some of its efficacy. Mass screening and treatment benefits asymptomatic P. falciparum carriers by clearing chronic infections, but in its current form holds little promise for malaria elimination. Hopes that "highly sensitive" diagnostic tests would provide substantial advances in screen and treat programmes have been shown to be misplaced. To reduce the burden on P. falciparum and Plasmodium vivax infections in people working in forested areas novel approaches to the use of malaria prophylaxis in forest workers should be explored. During an October 2019 workshop in Phnom Penh researchers and policymakers reviewed evidence of acceptability, feasibility and effectiveness of interventions to target malaria foci and interrupt P. falciparum transmission and discussed operational requirements and conditions for programmatic implementation.
Assuntos
Testes Diagnósticos de Rotina , Erradicação de Doenças/instrumentação , Malária Falciparum/prevenção & controle , Administração Massiva de Medicamentos , Programas de Rastreamento , Antimaláricos/uso terapêutico , Camboja , Humanos , Administração Massiva de Medicamentos/economiaRESUMO
The emergence and spread of drug resistance in the Greater Mekong Subregion (GMS) have added urgency to accelerate malaria elimination while reducing the treatment options. The remaining foci of malaria transmission are often in forests, where vectors tend to bite during daytime and outdoors, thus reducing the effectiveness of insecticide-treated bed nets. Limited periods of exposure suggest that chemoprophylaxis could be a promising strategy to protect forest workers against malaria. Here we discuss three major questions in optimizing malaria chemoprophylaxis for forest workers: which antimalarial drug regimens are most appropriate, how frequently the chemoprophylaxis should be delivered, and how to motivate forest workers to use, and adhere to, malaria prophylaxis.
Assuntos
Malária/prevenção & controle , Animais , Antimaláricos/uso terapêutico , Sudeste Asiático/epidemiologia , Quimioprevenção/tendências , Florestas , Humanos , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/transmissãoRESUMO
BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy worldwide. Primaquine is the only licensed drug that effectively removes Plasmodium vivax hypnozoites from the human host and prevents relapse. While well tolerated by most recipients, primaquine can cause haemolysis in G6PD deficient individuals and is, therefore, underused. Rapid diagnostic tests (RDTs) could permit ascertainment of G6PD status outside of laboratory settings and hence safe treatment in remote areas. The performance of the fluorescent spot test (Trinity, Ireland; FST) and a G6PD RDT (Carestart, USA) against spectrophotometry were assessed. METHODS: Participants were enrolled during cross-sectional surveys in Laos and by purposive sampling in Cambodia. FST and RDT were performed during village surveys and 3 mL of venous blood was collected for subsequent G6PD measurement by spectrophotometry. RESULTS: A total of 757 participants were enrolled in Laos and 505 in Cambodia. FST and RDT performed best at 30% cut-off activity and performed significantly better in Laos than in Cambodia. When defining intermediate results as G6PD deficient, the FST had a sensitivity of 100% (95%CI 90-100) and specificity of 90% (95%CI 87.7-92.2) in Laos and sensitivity of 98% (94.1-99.6) and specificity of 71% (95%CI 66-76) in Cambodia (p < 0.001). The RDT had sensitivity and specificity of 100% (95%CI 90-100) and 99% (95%CI 97-99) in Laos and sensitivity and specificity of 91% (86-96) and 93% (90-95) in Cambodia (p < 0.001). The RDT performed significantly better (all p < 0.05) than the FST when intermediate FST results were defined as G6PD deficient. CONCLUSION: The interpretation of RDT results requires some training but is a good alternative to the FST. Trial registration clinicaltrials.gov; NCT01872702; 06/27/2013; https://clinicaltrials.gov/ct2/show/NCT01872702.
Assuntos
Testes Diagnósticos de Rotina/métodos , Teste em Amostras de Sangue Seco/métodos , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Glucosefosfato Desidrogenase/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Camboja , Criança , Pré-Escolar , Testes Diagnósticos de Rotina/instrumentação , Teste em Amostras de Sangue Seco/instrumentação , Feminino , Humanos , Laos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND: Cambodia has seen a marked reduction in the incidence of Plasmodium falciparum over the past decade without a corresponding decline in Plasmodium vivax incidence. It is unknown to what extent local transmission is sustained by a chain of clinical and sub-clinical infections or by continued re-introduction via migration. Using an ultrasensitive molecular technique, 20 villages in western Cambodia were surveyed to detect the low season prevalence of P. falciparum and P. vivax and local treatment records were reviewed. METHODS: During March to May 2015 cross-sectional surveys were conducted in 20 villages in Battambang, western Cambodia. Demographic and epidemiological data and venous blood samples were collected from 50 randomly selected adult volunteers in each village. Blood was tested for Plasmodium infections by rapid diagnostic test (RDT), microscopy and high volume (0.5 ml packed red blood cell) quantitative polymerase chain reaction (uPCR). Positive samples were analysed by nested PCR to determine the Plasmodium species. Malaria case records were collected from the Provincial Health Department and village malaria workers to determine incidence and migration status. RESULTS: Among the 1000 participants, 91 (9.1%) were positive for any Plasmodium infection by uPCR, seven (0.7%) by microscopy, and two (0.2%) by RDT. uPCR P. vivax prevalence was 6.6%, P. falciparum 0.7%, and undetermined Plasmodium species 1.8%. Being male (adjusted OR 2.0; 95% CI 1.2-3.4); being a young adult <30 years (aOR 2.1; 95% CI 1.3-3.4); recent forest travel (aOR 2.8; 95% CI 1.6-4.8); and, a history of malaria (aOR 5.2; 95% CI 2.5-10.7) were independent risk factors for parasitaemia. Of the clinical malaria cases diagnosed by village malaria workers, 43.9% (297/634) and 38.4% (201/523) were among migrants in 2013 and in 2014, respectively. Plasmodium vivax prevalence determined by uPCR significantly correlated with vivax malaria incidences in both 2014 and 2015 (p = 0.001 and 0.002, respectively), whereas no relationship was observed in falciparum malaria (p = 0.36 and p = 0.59, respectively). DISCUSSION: There was heterogeneity in the malaria parasite reservoir between villages, and Plasmodium prevalence correlated with subsequent malaria incidence. The association was attributable chiefly to P. vivax infections, which were nine-fold more prevalent than P. falciparum infections. In the absence of a radical cure with 8-aminoquinolines, P. vivax transmission will continue even as P. falciparum prevalence declines. Migration was associated with over a third of incident cases of clinical malaria. Trial registration clinicaltrials.gov (NCT01872702). Registered 4 June 2013.