Pratana Satitvipawee

Predictors of malaria-association with rubber plantations in Thailand

BackgroundThe national Global Fund-supported malaria (GFM) program in Thailand, which focuses on the household-level implementation of vector control via insecticide-treated nets (ITNs)/long-lasting insecticidal nets (LLINs) combined with indoor residual spraying (IRS), has been combating malaria risk situations in different provinces with complex epidemiological settings. By using the perception of malaria villagers (MVs), defined as villagers who recognized malaria burden and had local understanding of mosquitoes, malaria, and ITNs/LLINs and practiced preventive measures, this study investigated the predictors for malaria that are associated with rubber plantations in an area of high household-level implementation coverage of IRS (2007–2010) and ITNs/LLINs (2008–2010) in Prachuap Khiri Khan Province.MethodsA structured questionnaire addressing socio-demographics, household characteristics and health behavioral factors (knowledge, perceptions and practices) regarding the performed interventions was administered to the 313 households (70 malaria-affected and 243 malaria-unaffected) that had respondents aged ≥18 years of both genders. In the univariate and multivariate analyses, only 246 (78.6%) MV respondents (62 malaria-affected and 184 malaria-unaffected) were analyzed to determine the predictors for risk (morbidity).ResultsThe majority (70%) of households were covered by IRS. For a combination of ITNs/LLINs, there were 74% of malaria-affected households covered and 46% of malaria-unaffected households. In a logistic regression analysis using odds ratios (aORs) adjusted on the variables and a 95% confidence interval (CI), malaria affecting MVs was associated with daily worker (i.e., earning daily income by normally practicing laborious activities mostly in agriculture such as rubber tapping and rubber sheet processing at the smallholdings of rubber plantations) (aOR = 2.9, 95% CI: 1.1-7.4), low-moderate level of malaria knowledge (aOR = 2.4, 95% CI: 1.1-5.0) and sleeping under mosquito-nets (nets/ITNs/LLINs intermittently and ITNs/LLINs only) (aOR = 2.0, 95% CI: 1.0-3.7).ConclusionsThe MV predictors for malaria-association with rubber plantations included occupation (daily worker), misconceptions about malaria (mosquito and prevention) and the use of mosquito-nets. Human practices such as revisiting rubber plantations while exposed to multiple bites at multiple locations are more likely to apply to daily workers than to rubber farmers/tappers and others. The promotion and use of ITNs/LLINs depends substantially on cultural factors and defensive behaviors relevant to their occupational risk despite the perceived threats of malaria and the perceived benefits of ITNs/LLINs. This information supports the conclusion that GFM program implementation in Thailand or elsewhere for malaria-associated with rubber plantations would benefit from the potential use of ITNs/LLINs and changes in personal protection behaviors.

A Comparison of Population Size Estimators under the Truncated Count Model With and Without Allowance for Contaminations

The purpose of the study is to estimate the population size under a homogeneous truncated count model and under model contaminations via the Horvitz-Thompson approach on the basis of a count capture-recapture experiment. The proposed estimator is based on a mixture of zero-truncated Poisson distributions. The benefit of using the proposed model is statistical inference of the long-tailed or skewed distributions and the concavity of the likelihood function with strong results available on the nonparametric maximum likelihood estimator (NPMLE). The results of comparisons, for finding the appropriate estimator among McKendricks, Mantel-Haenszels, Zeltermans, Chaos, the maximum likelihood, and the proposed methods in a simulation study, reveal that under model contaminations the proposed estimator provides the best choice according to its smallest bias and smallest mean square error for a situation of sufficiently large population sizes and the further results show that the proposed estimator performs well even for a homogeneous situation. The empirical examples, containing the cholera epidemic in India based on homogeneity and the heroin user data in Bangkok 2002 based on heterogeneity, are fitted with an excellent goodness-of-fit of the models and the confidence interval estimations may also be of considerable interest.

HIV incidence rates among drug users in northern Thailand, 1993–7

Drug use is a major mode of HIV transmission in Thailand. This study determined HIV incidence rates among drug users in a regional drug treatment centre in northern Thailand. A retrospective cohort of repeatedly-hospitalized drug users between 1993 and 1997 was formed and HIV incidence rates were calculated. The overall incidence was 11.44 per 100 person-years of observation. Gender, age, religion, ethnicity, education, employment, income, reasons for drug use, type of drugs, mode of use, spending on drugs, and referral for treatment are associated with HIV incidence. However, there are no associations between HIV incidence and history of treatment and mode of discharge from the centre. This implies that current treatment modality has no impact on HIV infection risk and other therapeutic approaches should be explored.

The Impact of Cigarette Plain Packaging on Health Warning Salience and Perceptions: Implications for Public Health Policy

The study employed a mixed methods design using focus group interviews with 6 student groups and self-administered questionnaires with 1239 students. The participants were nonsmoking, current smokers, and quit-smoking teenagers from secondary schools and colleges. Focus group revealed that although nonsmoking teenagers perceived fear appeals to warning messages, current smokers did not perceive fear appeals to health. Black and white backgrounds of the cigarette package were chosen as the best color for plain packaging. However, most participants suggested various pictorials and a bigger size of pictorial warnings for greater and more effective fear appeal. Odds ratio showed that males had 2.43 times the odds to perceive intention not to smoke. Teenagers who had never smoked and those who had quit smoking had 13.27 and 3.61 times the odds, respectively, to perceive intention not to smoke.

Homocysteine but not Serum Amyloid A, Vitamin A and E Related to Increased Risk of Metabolic Syndrome in Post-Menopausal Thai Women

This study aims to investigate serum amyloid A, homocysteine, and biochemical-anthropometric measurements in post-menopausal women with and without metabolic syndrome (MS), and determine whether serum amyloid A and homocysteine are linked to MS among this group. This study was performed with 405 post-menopausal Thai volunteers with a mean age of 57.95±5.90 years (135 subjects with MS and 270 subjects without MS). The levels of serum amyloid A, homocysteine, vitamins, glucose, and lipids were measured. Homocysteine levels were significantly higher in the group with MS than in that without MS (p<0.001), whereas for serum amyloid A, vitamin A, vitamin E and vitamin B12, there were no significant differences. There were significant differences between the groups in folate, HDL-C, and anthropometric measurements (p<0.001). Thirty seven percent of the group with MS and 14.1% of the group without MS were classified as having hyperhomocysteinemia (p<0.001). Furthermore, logistic regression analysis revealed that hyperhomocysteinemia (odds ratio (OR): 2.67, 95% confidence interval (95%CI): 1.57-4.58), low folate (OR: 1.79, 95%CI: 1.11-2.89), and BMI (OR: 1.25, 95%CI: 1.16-1.33) were significantly related to MS. These findings suggest that increased homocysteine levels and decreased folate concentrations may influence susceptibility to MS and this effect may be an early event in the development of cardiovascular diseases among post-menopausal women. Therefore, there is a need to evaluate homocysteine levels, especially among post-menopausal Thai women.

Internet Cigarette and Tobacco Business (ICTB) Database for Domestic Markets in Thailand

This research presents a cross-sectional survey for monitoring and analysis of illegal sales of cigarettes or tobacco products on the internet in Thailand from June 2010 to June 2014. The websites are collected monthly and classified into four categories: blog, webboard, social network and online shopping. First the data was gathered by using manpower and later by an algorithm program. Each data category is separately analyzed and carried out to gather information from the details of tobacco products and websites such as product types, brands, prices, promotions, and payment methods. The databases are later submitted to three regulators, Thai Hotline, Royal Thai Police, and ICT, to close the websites and arrest distributors.

E-Referral System by Means of Decision Support System

This research aims to study, analyze, design and develop a web-based referral system for the recommendation of appropriate referred hospitals. Decision support system is applied to reduce time to find provider information that qualify with referral policy, medical specialists, bed, healthcare coverage, how emergency, distance and transportation time. This e-referral system scopes referral area from Siriraj hospital to other health care providers in Bangkok and metropolitan region (Nakhon Pathom, Nonthaburi, Pathum Thani, Samut Prakan and Samut Sakhon), with a total of 240 hospitals. This approach uses a rule-based system to match providers with Siriraj referral policy. Then, these matched providers’ data are analyzed to calculate its weight value.