Climate change and health in Southeast Asia - defining research priorities and the role of the Wellcome Trust Africa Asia Programmes

This article summarises a recent virtual meeting organised by the Oxford University Clinical Research Unit in Vietnam on the topic of climate change and health, bringing local partners, faculty and external collaborators together from across the Wellcome and Oxford networks. Attendees included invited local and global climate scientists, clinicians, modelers, epidemiologists and community engagement practitioners, with a view to setting priorities, identifying synergies and fostering collaborations to help define the regional climate and health research agenda. In this summary paper, we outline the major themes and topics that were identified and what will be needed to take forward this research for the next decade. We aim to take a broad, collaborative approach to including climate science in our current portfolio where it touches on infectious diseases now, and more broadly in our future research directions. We will focus on strengthening our research portfolio on climate-sensitive diseases, and supplement this with high quality data obtained from internal studies and external collaborations, obtained by multiple methods, ranging from traditional epidemiology to innovative technology and artificial intelligence and community-led research. Through timely agenda setting and involvement of local stakeholders, we aim to help support and shape research into global heating and health in the region.

Climate change and health in Southeast Asia - defining research priorities and the role of the Wellcome Trust Africa Asia Programmes

This article summarises a recent virtual meeting organised by the Oxford University Clinical Research Unit in Vietnam on the topic of climate change and health, bringing local partners, faculty and external collaborators together from across the Wellcome and Oxford networks. Attendees included invited local and global climate scientists, clinicians, modelers, epidemiologists and community engagement practitioners, with a view to setting priorities, identifying synergies and fostering collaborations to help define the regional climate and health research agenda. In this summary paper, we outline the major themes and topics that were identified and what will be needed to take forward this research for the next decade. We aim to take a broad, collaborative approach to including climate science in our current portfolio where it touches on infectious diseases now, and more broadly in our future research directions. We will focus on strengthening our research portfolio on climate-sensitive diseases, and supplement this with high quality data obtained from internal studies and external collaborations, obtained by multiple methods, ranging from traditional epidemiology to innovative technology and artificial intelligence and community-led research. Through timely agenda setting and involvement of local stakeholders, we aim to help support and shape research into global heating and health in the region.

Climate change and health in Southeast Asia - defining research priorities and the role of the Wellcome Trust Africa Asia Programmes

This article summarises a recent virtual meeting organised by the Oxford University Clinical Research Unit in Vietnam on the topic of climate change and health, bringing local partners, faculty and external collaborators together from across the Wellcome and Oxford networks. Attendees included invited local and global climate scientists, clinicians, modelers, epidemiologists and community engagement practitioners, with a view to setting priorities, identifying synergies and fostering collaborations to help define the regional climate and health research agenda. In this summary paper, we outline the major themes and topics that were identified and what will be needed to take forward this research for the next decade. We aim to take a broad, collaborative approach to including climate science in our current portfolio where it touches on infectious diseases now, and more broadly in our future research directions. We will focus on strengthening our research portfolio on climate-sensitive diseases, and supplement this with high quality data obtained from internal studies and external collaborations, obtained by multiple methods, ranging from traditional epidemiology to innovative technology and artificial intelligence and community-led research. Through timely agenda setting and involvement of local stakeholders, we aim to help support and shape research into global heating and health in the region.

Using Land Runoff to Survey the Distribution and Genetic Diversity of Burkholderia pseudomallei in Vientiane, Laos

Melioidosis is a disease of significant public health importance that is being increasingly recognized globally. The majority of cases arise through direct percutaneous exposure to its etiological agent, Burkholderia pseudomallei In the Lao People's Democratic Republic (Laos), the presence and environmental distribution of B. pseudomallei are not well characterized, though recent epidemiological surveys of the bacterium have indicated that B. pseudomallei is widespread throughout the environment in the center and south of the country and that rivers can act as carriers and potential sentinels for the bacterium. The spatial and genetic distribution of B. pseudomallei within Vientiane Capital, from where the majority of cases diagnosed to date have originated, remains an important knowledge gap. We sampled surface runoff from drain catchment areas throughout urban Vientiane to determine the presence and local population structure of the bacterium. B. pseudomallei was detected in drainage areas throughout the capital, indicating it is widespread in the environment and that exposure rates in urban Vientiane are likely more frequent than previously thought. Whole-genome comparative analysis demonstrated that Lao B. pseudomallei isolates are highly genetically diverse, suggesting the bacterium is well-established and not a recent introduction. Despite the wide genome diversity, one environmental survey isolate was highly genetically related to a Lao melioidosis patient isolate collected 13 years prior to the study. Knowledge gained from this study will augment understanding of B. pseudomallei phylogeography in Asia and enhance public health awareness and future implementation of infection control measures within Laos.IMPORTANCE The environmental bacterium B. pseudomallei is the etiological agent of melioidosis, a tropical disease with one model estimating a global annual incidence of 165,000 cases and 89,000 deaths. In the Lao People's Democratic Republic (Laos), the environmental distribution and population structure of B. pseudomallei remain relatively undefined, particularly in Vientiane Capital from where most diagnosed cases have originated. We used surface runoff as a proxy for B. pseudomallei dispersal in the environment and performed whole-genome sequencing (WGS) to examine the local population structure. Our data confirmed that B. pseudomallei is widespread throughout Vientiane and that surface runoff might be useful for future environmental monitoring of the bacterium. B. pseudomallei isolates were also highly genetically diverse, suggesting the bacterium is well-established and endemic in Laos. These findings can be used to improve awareness of B. pseudomallei in the Lao environment and demonstrates the epidemiological and phylogeographical insights that can be gained from WGS.

Methods for Testing the Quality Attributes of Plant-Based Foods: Meat- and Processed-Meat Analogs

The modern food system is seeing a change in consumption patterns provoked by several drivers—including ethical, health, and environmental concerns—that are increasing the sales of meat analog foods. This change is accompanied by increased research and development activities in the area of plant-based meats. The aim of the present review is to describe methods that are being employed by scientists to analyze and characterize the properties of meat alternatives and to propose standardized methods that could be utilized in the future. In particular, methods to determine the proximate composition, microstructure, appearance, textural properties, water-holding properties, cooking resilience, and sensory attributes, of plant-based meat are given. The principles behind these methods are presented, their utility is critically assessed, and practical examples will be discussed. This article will help to guide further studies and to choose appropriate methods to assess raw materials, processes, products, and consumption behavior of meat analogs.

The ecosystem approach to health is a promising strategy in international development: lessons from Japan and Laos

BACKGROUND

An ecological perspective was prominently present in the health promotion movement in the 1980s, but this seems to have faded. The burden of disease the developing world is facing cannot be addressed solely by reductionist approaches. Holistic approaches are called for that recognize the fundamentally interdependent nature of health and other societal, developmental, and ecosystem related factors in human communities. An ecosystem approach to human health (ecohealth) provides a good starting point to explore these interdependencies.

DISCUSSION

Development assistance is often based on the assumption that developed countries can serve as models for developing ones. Japan has provided lavish assistance to Laos for example, much of it going to the development of transport networks. However, there is little sign that there is an awareness of the potentially negative environmental and health impacts of this assistance. We argue that the health consequences of environmental degradation are not always understood, and that developing countries need to consider these issues. The ecohealth approach is useful when exploring this issue. We highlight three implications of the ecohealth approach: (1) The WHO definition of health as a state of complete physical, mental and social well-being emphasized that health is more than the absence of disease. However, because this approach may involve an unattainable goal, we suggest that health should be defined in the ecosystem context, and the goal should be to attain acceptable and sustainable levels of health through enabling people to realize decent livelihoods, and to pursue their life purpose; (2) The increasing interconnectedness of ecosystems in a globalizing world requires an ethical approach that considers human responsibility for the global biosphere. Here, ecohealth could be a countervailing force to our excessive concentration on economy and technology; and (3) If ecohealth is to become a positive agent of change in the global health promotion movement, it will have to find a secure place in the educational curriculum. This article presents a brief case study of Japan's development assistance to Laos, and its environmental and health implications, as an illustration of the ecohealth approach. We highlight three implications of the ecohealth perspective.

Thiamin supplementation does not reduce the frequency of adverse events after anti-malarial therapy among patients with falciparum malaria in southern Laos

BACKGROUND

In a recent study one third of Lao patients presenting with uncomplicated Plasmodium falciparum malaria had biochemical evidence of thiamin deficiency, which was associated with a higher incidence of adverse events. Thiamin supplementation might, therefore, reduce adverse events in this population.

METHODS

An exploratory, double-blind, parallel group, placebo-controlled, superiority trial of thiamin supplementation in patients of all ages with uncomplicated and severe falciparum malaria was conducted in Xepon District, Savannakhet Province, southern Laos. Patients were randomly assigned to either oral thiamin 10 mg/day for 7 days immediately after standard anti-malarial treatment then 5 mg daily until day 42, or identical oral placebo.

RESULTS

After interim analyses when 630 patients (314 in thiamin and 316 in placebo groups) had been recruited, the trial was discontinued on the grounds of futility. On admission biochemical thiamin deficiency (alpha ≥ 25%) was present in 27% of patients and 9% had severe deficiency (alpha > 31%). After 42 days of treatment, the frequency of thiamin deficiency was lower in the thiamin (2%, 1% severe) compared to the placebo (11%, 3% severe) groups (p < 0.001 and p = 0.05), respectively. Except for diarrhoea, 7% in the placebo compared to 3% in the thiamin group (p = 0.04), and dizziness on day 1 (33% vs 25%, p = 0.045), all adverse events were not significantly different between the groups (p > 0.05). Clinical, haematological, and parasitological responses to treatment did not differ significantly between the two groups.

CONCLUSION

Thiamin supplementation reduced biochemical thiamin deficiency among Lao malaria patients following anti-malarial drug treatment, but it did not reduce the frequency of adverse events after anti-malarial therapy or have any detected clinical or parasitological impact.

TRIAL REGISTRATION

ISRCTN 85411059.

Job satisfaction of health-care workers at health centers in Vientiane Capital and Bolikhamsai Province, Lao PDR

The aim of this study was to assess job satisfaction levels among health-care workers and factors correlated with their overall job satisfaction. This cross-sectional study was conducted from July to September 2011 with 164 health-care workers using self-administered questionnaires on a six-point Likert scale. Categorical variables were reported using frequencies and median (interquartile range), while continuous data were using means and standard deviations. Spearman rho coefficients were computed to correlate the overall job satisfaction for each factor, Kruskal-Wallis and Mann-Whitney U tests were used to evaluate the differences between demographic characteristics on overall job satisfaction. Of the 164 respondents, the majority were females (65.85%). Other dominant variables were married (76.83%), age > or =41 years old (44.51%), certified heath professional level (96.30%), nurse profession (59.10%), and working experience < or =5 years (55.49%). Participants were satisfied with 17 factors, but dissatisfied with salary levels at a mean score of (3.25). The highest satisfaction reported was for the freedom to choose the method of working with a mean score of 4.99, followed by the amount of variety on the job (4.96), amount of responsibility (4.90), and relationships with co-workers (4.90). The correlation coefficient between overall job satisfaction and main factors for job satisfaction-conflict resolution at work, relationships with co-workers, and organizational structure were (0.79), (0.76), and (0.71), respectively. There were statistically significant differences in age group, working experience and position (P<0.05). In conclusion, health-care workers at health centers in Lao PDR were generally satisfied with their job except for their salary. The main factors that correlate with their overall job satisfaction were conflict resolutions at work, relationships with other co-workers, and organizational structure.

Evaluation of a rapid colorimetric field test to assess the effective life of long-lasting insecticide-treated mosquito nets in the Lao PDR

BACKGROUND

Malaria morbidity and mortality have been significantly reduced through the proper use of insecticide-treated mosquito nets, but the extra protection afforded by the insecticide diminishes over time. The insecticide depletion rates vary according to location where wash frequency and wear are influenced by cultural habits as well as the availability of water. Monitoring of available insecticides on the net surface is essential for determining the effective life of the net. Therefore, a rapid and inexpensive colorimetric field test for cyanopyrethroids (Cyanopyrethroid Field Test or CFT) was used to measure surface levels of deltamethrin on insecticide-coated polyester nets (PowerNets™) in rural Lao PDR over a two-year period.

METHODS

Net surface levels of deltamethrin were measured by wiping the net with filter paper and measuring the adsorbed deltamethrin using the CFT. A relationship between surface levels of deltamethrin and whole net levels was established by comparing results of the CFT with whole levels assayed by high-performance liquid chromatography (HPLC). An effective deltamethrin surface concentration (EC80) was determined by comparing mosquito mortality (WHO Cone Test) with CFT and HPLC results. Five positions (roof to bottom) on each of 23 matched nets were assayed for deltamethrin surface levels at 6, 12, and 24 months. Mosquito mortality assays (WHO Cone Tests) were performed on a subset of eleven 24-month old nets and compared with the proportion of failed nets as predicted by the CFT.

RESULTS

At six months, the nets retained about 80% of the baseline (new net) levels of deltamethrin with no significant differences between net positions. At 12 months, ~15-40%, and at 24 months <10% of deltamethrin was retained on the nets, with significant differences appearing between positions. Results from the CFT show that 93% of the nets failed (deltamethrin surface levels

CONCLUSION

The CFT is a useful and accurate indicator of net efficacy and may be substituted for mosquito bioassays.

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Key Words

• permanet
• itn
• llin
• deltamethrin
• colorimetric
• bioassay
• mosquito
• malaria
• net
• lao pdr
• laos

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MESH Headings

• Animals
• Biological Assay
• Chemistry Techniques, Analytical/economics
• Chemistry Techniques, Analytical/methods
• Colorimetry/economics
• Colorimetry/methods
• Culicidae/drug effects
• Insecticide-Treated Bednets
• Insecticides/analysis
• Insecticides/pharmacology
• Laos
• Nitriles/analysis
• Nitriles/pharmacology
• Point-of-Care Systems/economics
• Pyrethrins/analysis
• Pyrethrins/pharmacology
• Survival Analysis
• Time Factors

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Grants

• 089275 Wellcome Trust

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Affiliation(s)

Michael D Green Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
Mayfong Mayxay Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao PDR, Laos Faculty of Postgraduate Studies, University of Health Sciences, Vientiane, Lao PDR, Laos Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, Nuffield Department of Medicine, University of Oxford, Oxford, UK
Ray Beach Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
Tiengkham Pongvongsa Savannakhet Provincial Malaria Station, Savannakhet Province, Lao PDR, Laos
Samlane Phompida Centre of Malariology, Parasitology and Entomology, Ministry of Health, Vientiane, Lao PDR, Laos
Bouasy Hongvanthong Centre of Malariology, Parasitology and Entomology, Ministry of Health, Vientiane, Lao PDR, Laos
Viengxay Vanisaveth Centre of Malariology, Parasitology and Entomology, Ministry of Health, Vientiane, Lao PDR, Laos
Paul N Newton Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao PDR, Laos Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, Nuffield Department of Medicine, University of Oxford, Oxford, UK
Lucrecia Vizcaino Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
Isabel Swamidoss Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA

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Facilitators and barriers to accessing reproductive health care for migrant beer promoters in Cambodia, Laos, Thailand and Vietnam: a mixed methods study

BACKGROUND

The purpose of the research was to assess access to sexual and reproductive health services for migrant women who work as beer promoters. This mixed methods research was conducted in Phnom Penh, Cambodia, Bangkok, Thailand, Vientiane, Laos, and Hanoi, Vietnam during 2010 to 2011.

METHODS

Focus groups were held with beer promoters and separate focus groups or interviews with key informants to explore the factors affecting beer promoters' access to health care institutions for reproductive health care. The findings of the focus groups were used to develop a survey for beer promoters. This survey was conducted in popular health institutions for these women in each of the four Asian cities.

RESULTS

Several common themes were evident. Work demands prevented beer promoters from accessing health care. Institutional factors affecting care included cost, location, environmental factors (e.g. waiting times, cleanliness and confidentiality) and service factors (e.g. staff attitudes, clinic hours, and availability of medications). Personal factors affecting access were shyness and fear, lack of knowledge, and support from family and friends.The survey of the beer promoters confirmed that cost, location and both environmental and service factors impact on access to health care services for beer promoters. Many beer promoters are sexually active, and a significant proportion of those surveyed rely on sex work to supplement their income. Many also drink with their clients. Despite a few differences amongst the surveyed population, the findings were remarkably similar across the four research sites.

CONCLUSIONS

Recommendations from the research include the provision of evening and weekend clinic hours to facilitate access, free or low cost clinics, and health insurance through employer or government plans which are easy to access for migrants. Other improvements that would facilitate the access of beer promoters to these services include increased funding to hire more staff (reducing waiting times) and to stock more needed medications, mobile clinics to come to the workplace or free transportation for beer promoters to the clinics, improved training to reduce health care provider stigma against beer promoters, and public education about the importance of reproductive health care, including preventative services.

An ethnobotanical survey of medicinal plants of Laos toward the discovery of bioactive compounds as potential candidates for pharmaceutical development

CONTEXT

An ethnobotany-based approach in the selection of raw plant materials to study was implemented.

OBJECTIVE

To acquire raw plant materials using ethnobotanical field interviews as starting point to discover new bioactive compounds from medicinal plants of the Lao People's Democratic Republic.

METHODS

Using semi-structured field interviews with healers in the Lao PDR, plant samples were collected, extracted, and bio-assayed to detect bioactivity against cancer, HIV/AIDS, TB, malaria. Plant species demonstrating activity were recollected and the extracts subjected to a bioassay-guided isolation protocol to isolate and identify the active compounds.

RESULTS

Field interviews with 118 healers in 15 of 17 provinces of Lao PDR yielded 753 collections (573 species) with 955 plant samples. Of these 955, 50 extracts demonstrated activity in the anticancer, 10 in the anti-HIV, 30 in the anti-TB, and 52 in the antimalarial assay. Recollection of actives followed by bioassay-guided isolation processes yielded a series of new and known in vitro-active anticancer and antimalarial compounds from 5 species.

DISCUSSION

Laos has a rich biodiversity, harboring an estimated 8000-11,000 species of plants. In a country highly dependent on traditional medicine for its primary health care, this rich plant diversity serves as a major source of their medication.

CONCLUSIONS

Ethnobotanical survey has demonstrated the richness of plant-based traditional medicine of Lao PDR, taxonomically and therapeutically. Biological assays of extracts of half of the 955 samples followed by in-depth studies of a number of actives have yielded a series of new bioactive compounds against the diseases of cancer and malaria.

Ethnobotanical approach versus random approach in the search for new bioactive compounds: support of a hypothesis

CONTEXT

Whether natural product drug discovery programs should rely on wild plants collected "randomly" from the natural environment, or whether they should also include plants collected on the basis of use in traditional medicine remains an open question.

OBJECTIVE

This study analyzes whether plants with ethnomedical uses from Vietnam and Laos have a higher hit rate in bioassay testing than plants collected from a national park in Vietnam with the goal of maximizing taxonomic diversity ("random" collection).

MATERIALS AND METHODS

All plants were extracted and subjected to bioassay in the same laboratories. Results of assays of plant collections and plant parts (samples) were scored as active or inactive based on whether any extracts had a positive result in a bioassay. Contingency tables were analyzed using χ(2) statistics.

RESULTS

Random collections had a higher hit rate than ethnomedical collections, but for samples, ethnomedical plants were more likely to be active. Ethnomedical collections and samples had higher hit rates for tuberculosis, while samples, but not collections, had a higher hit rate for malaria. Little evidence was found to support an advantage for ethnomedical plants in HIV, chemoprevention and cancer bioassays. Plants whose ethnomedical uses directly correlated to a bioassay did not have a significantly higher hit rate than random plants.

DISCUSSION

Plants with ethnomedical uses generally had a higher rate of activity in some drug discovery bioassays, but the assays did not directly confirm specific uses.

CONCLUSIONS

Ethnomedical uses may contribute to a higher rate of activity in drug discovery screening.

Indigenous utilization of termite mounds and their sustainability in a rice growing village of the central plain of Laos

BACKGROUND

The objective of this study was to investigate the indigenous utilization of termite mounds and termites in a rain-fed rice growing village in the central plain of Laos, where rice production is low and varies year-to-year, and to assess the possibility of sustainable termite mound utilization in the future. This research was carried out from 2007 to 2009.

METHODS

The termites were collected from their mounds and surrounding areas and identified. Twenty villagers were interviewed on their use of termites and their mounds in the village. Sixty-three mounds were measured to determine their dimensions in early March, early July and middle to late November, 2009.

RESULTS

Eleven species of Termitidae were recorded during the survey period. It was found that the villagers use termite mounds as fertilizer for growing rice, vegetable beds and charcoal kilns. The villagers collected termites for food and as feed for breeding fish. Over the survey period, 81% of the mounds surveyed increased in volume; however, the volume was estimated to decrease by 0.114 m3 mound(-1) year(-1) on average due to several mounds being completely cut out.

CONCLUSION

It was concluded that current mound utilization by villagers is not sustainable. To ensure sustainable termite utilization in the future, studies should be conducted to enhance factors that promote mound restoration by termites. Furthermore, it will be necessary to improve mound conservation methods used by the villagers after changes in the soil mass of mounds in paddy fields and forests has been measured accurately. The socio-economic factors that affect mound utilization should also be studied.

Socioeconomic determinants of nutritional status of children in Lao PDR: effects of household and community factors

The prevalence of undernutrition among Lao children is among the highest in the region. However, the determinants of childhood undernutrition in Laos have not been fully analyzed. This paper, using the dataset of the Lao Multiple Indicator Cluster Survey 3, which is a nationally-representative sample in Laos, investigated the effects of socioeconomic factors at both household and community levels on the nutritional status of children. In the estimation, a multilevel linear model with random-intercepts was used for estimating the determinants of child anthropometric indices. The empirical results revealed that children from households in southern Laos and from ethnic minority groups were less-nourished. Level of education of parents, attitudes of mothers towards domestic violence, assets of household, local health services, and the condition of sanitation and water were considered to be important determinants of nutritional status of children. The pattern of growth-faltering in children by age was identified. Children aged 12-59 months were less-nourished than those aged 0-11 months. The empirical results were consistent with the collective household model which incorporates a decision-making process within the household. Since there is scarce evidence about the predictors of childhood undernutrition in Laos, the findings of this study will serve as a benchmark for future research.

Predictive diagnostic value of the tourniquet test for the diagnosis of dengue infection in adults

OBJECTIVE

To examine the accuracy of the admission tourniquet test in the diagnosis of dengue infection among Lao adults.

METHODS

Prospective assessment of the predictive diagnostic value of the tourniquet test for the diagnosis of dengue infection, as defined by IgM, IgG and NS1 ELISAs (Panbio Ltd, Australia), among Lao adult inpatients with clinically suspected dengue infection.

RESULTS

Of 234 patients with clinically suspected dengue infection on admission, 73% were serologically confirmed to have dengue, while 64 patients with negative dengue serology were diagnosed as having scrub typhus (39%), murine typhus (11%), undetermined typhus (12%), Japanese encephalitis virus (5%), undetermined flavivirus (5%) and typhoid fever (3%); 25% had no identifiable aetiology. The tourniquet test was positive in 29.1% (95% CI = 23.2-34.9%) of all patients and in 34.1% (95% CI = 27.0-41.2%) of dengue-seropositive patients, in 32.7% (95% CI = 23.5-41.8) of those with dengue fever and in 36.4% (95% CI = 24.7-48.0) of those with dengue haemorrhagic fever. Interobserver agreement for the tourniquet test was 90.2% (95% CI = 86.4-94.0) (Kappa = 0.76). Using ELISAs as the diagnostic gold standard, the sensitivity of the tourniquet test was 33.5-34%; its specificity was 84-91%. The positive and negative predictive values were 85-90% and 32.5-34%, respectively.

CONCLUSIONS

The admission tourniquet test has low sensitivity and adds relatively little value to the diagnosis of dengue among Lao adult inpatients with suspected dengue. Although a positive tourniquet test suggests dengue and that treatment of alternative diagnoses may not be needed, a negative test result does not exclude dengue.

Biological evaluation of plants of Laos used in the treatment of tuberculosis in Lao traditional medicine

Tuberculosis has existed in Southeast Asia for thousands of years. Many traditional treatments involve herbal remedies. Over time, these traditional treatments have had the chance to become refined based on efficacy and safety. It was therefore hypothesized that plants that were used in the past and are still used today to treat symptoms associated with tuberculosis are more likely to contain anti-tubercular compounds than plants that have not been used continuously. To try to deduce which plants were used in Laos in the past, a collection of palm leaf manuscripts was studied and a list of plants used to treat symptoms associated with tuberculosis was compiled. Interviews were then conducted with contemporary healers to see if the same plants are still being used today. Plants that were found in the manuscripts and/or are presently used by healers were collected, extracted and were evaluated in an anti-tubercular assay. This paper presents the methods used to identify and collect plants used to treat symptoms indicative of tuberculosis, and the results of anti-TB assays to test for activity.

Thiamin deficiency and uncomplicated falciparum malaria in Laos

OBJECTIVE

Thiamin deficiency complicates severe Plasmodium falciparum malaria in Thailand and may contribute to acidosis. We therefore estimated the frequency of biochemical thiamin deficiency in patients presenting with uncomplicated falciparum malaria in southern Laos.

METHODS

Red cell transketolase activation coefficients (alpha) were measured in 310 patients presenting with uncomplicated falciparum malaria and 42 days after starting treatment.

RESULTS

Twelve per cent of patients had biochemical evidence of severe deficiency (alpha values >1.31) at presentation, declining to 3% 42 days later.

CONCLUSION

Thiamin deficiency was common in Lao patients admitted with uncomplicated P. falciparum infection and was reduced following treatment of malaria and multivitamin supplementation. The role of this preventable and treatable disorder in malaria and other acute infections, and the incidence of beriberi in rural Laos, needs further investigation.