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This study aimed to determine temporal patterns and develop a forecasting model for dengue incidence in northeastern Thailand. Reported cases were obtained from the Thailand national surveillance system. The temporal patterns were displayed by plotting monthly rates, the seasonal-trend decomposition procedure based on loess (STL) was performed using R 2.2.1 software, and the trend was assessed using Poisson regression. The forecasting model for dengue incidence was performed in R 2.2.1 and Intercooled Stata 9.2 using the seasonal Autoregressive Integrated Moving Average (ARIMA) model. The model was evaluated by comparing predicted versus actual rates of dengue for 1996 to 2005 and used to forecast monthly rates during January to December 2006. The results reveal that epidemics occurred every two years, with approximately three years per epidemic, and that the next epidemic will take place in 2006 to 2008. It was found that if a month increased, the rate ratio for dengue infection decreased by a factor 0.9919 for overall region and 0.9776 to 0.9984 for individual provinces. The amplitude of the peak, which was evident in June or July, was 11.32 to 88.08 times greater than the rest of the year. The seasonal ARIMA (2, 1, 0) (0, 1, 1)12 model was model with the best fit for regionwide data of total dengue incidence whereas the models with the best fit varied by province. The forecasted regional monthly rates during January to December 2006 should range from 0.27 to 17.89 per 100,000 population. The peak for 2006 should be much higher than the peak for 2005. The highest peaks in 2006 should be in Loei, Buri Ram, Surin, Nakhon Phanom, and Ubon Ratchathani Provinces.

A case-control study was carried out to determine factors associated with HIV infection among pregnant hilltribe women who attended the antenatal clinics of six hospitals in northern Thailand (Mae Suai, Wieng Pa Pao, Mae Sai, Mae Chan, Wieng Kaen, Mae Fa Luang, and Chiang Rai hospitals) between 1 January 2005- 31 May 2007. Data were collected using questionnaires and analysis was by univariate (p-value = 0.100) and multivariate analysis (p-value = 0.050) in the model of unconditional multiple logistic regression. The ratio of cases to controls was 1:4. The sample consisted of 255 subjects; 51 cases and 204 controls. The mean age of the women was 26.9 years (min = 15, max = 52, and SD 7.3). The majority of the women were Lahu (49.8%) or Akha (36.9%). Nearly half the women were Christian (48.2%), followed by Buddhist (42.4%). Most of the women were not educated (60.4%). The largest group for family income was 10,000-49,999 baht/year (62.6%). After controlling for family income, family debt, education, occupation and household members, the findings showed that the "not married to debut partner" group were at greater risk than the "married to debut partner" group by 6.6 times (OR(adj) = 6.6, 95% CI = 2.9-14.9). The "use of alcohol" group were at higher risk by 4.5 times (OR(adj) = 4.5, 95% CI = 2.0-10.3) compared to the no alcohol use group, and a history of genital ulcer group had an increased risk of 6.3 times (OR(adj) = 6.3, 95% CI = 1.2-31.1) the chance of having HIV infection compared to no history of genital ulcers in pregnant hilltribe women.

Cancer of the uterine cervix is the second most common cancer in females in the world with about half a million new patients per year. Since the introduction by Papanicolaou of cervical smear screening, the incidence of cervical cancer has declined in many developed countries. The decrease in the incidence of and mortality from cervical cancer is mainly due to the organized mass screening using Pap smear programmes. Uterine cervical cancer is the leading cancer among women in Thailand with age-standardized incidence rates of 24.7 per 100,000 in 1999. Most cases present at advanced stages with poor prognoses of survival and cure. In the present study, cervical cancer screening programme with cervical cytology was organized for Nakhon Phanom province, Thailand. The specific objectives were: 1) to evaluate the reduction in incidence and mortality from cervical cancer in the province by means of an organised low-intensity cervical cytology programme. 2) to demonstrate the different aspects of programme implementation as a potential model for nationwide implementation. The screening activities were integrated in the existing health care system. Organized screening for women in the target population (aged 35-54 years) at 5-year intervals was free of charge. Sample taking was done by trained nurses (midwives) and primary health care personnel in the local health care centers. Sample quality was under continuous controlled by the cytology laboratories and pathologists. Confirmation and treatment were integrated into the normal health care routines. The screening results of the programme, including histologically confirmed diagnosis, were registered at the National Cancer Institute using PapReg and CanReg 4 programmes. A population-based cancer registry in Nakhon Phanom province was also set up in 1997. In the period 1999-2002, 32,632 women aged 35-54 years were screened. Women with low-grade lesions returned for routine follow-up smears. High-grade preinvasive disease was further evaluated by repeating Pap smear, conization or biopsy and subsequent treatment through surgical removal or ablation. This organized low-intensity cervical cytology programme showed a considerable increase in early carcinoma in situ and CIN II -III cases and should reduce incidence of and mortality from cervical cancer in Nakhon Phanom province in the future. Screening with the Papanicolaou smear plus adequate follow-up diagnosis and therapy can achieve major reductions in both incidence and mortality rates.

Objective: To study survival time and risk factors of mortality among HIV-infected patients who had cryptococcal meningitis., Design: Retrospective cohort study., Material and Method: Patients' medical records of those who had HIV-infection with newly diagnosed cryptoccocal meningitis between January 2002 and December 2004 were reviewed. Each patient was classified into one of two groups, according to their anti-retroviral status (ART)., Results: Five hundred and forty nine patients enrolled in the present study: 281 (51.2%) in the ART+ group and 268 (48.8%) in the ART-group. The mean age was 33.4 +/- 6.9 years old in the ART + group and 33.6 +/- 7.0 years old in the ART-group. There were more male in both groups: 207 males and 74 females in the ART+ group, and 195 males and 73 females in the ART-group. Baseline CD4 cell count of both groups was 20 (6-74) cells/mL and 24 (9-72) cells/ml. About 30% of both groups of patients experienced major opportunistic infection before cryptococcal meningitis. All patients were treated by standard amphotericin B for a 2-week duration followed by fluconazole for an additional 8 weeks. There were no differences of baseline characteristics between the two groups (p > 0.05). The survival rates at 12, 24, and 36 months were 92.8%, 87.4%, and 85.4% in the ART+ group and 55.3%, 42.2%, and 36.8% in the ART- group, respectively (p < 0.01). The median survival time in the ART- group was 15 months. From the Cox regression model, the hazard ratio for "not received ART" was 4.87 (95%CI = 2.48-9.44, p < 0.01)., Conclusion: The present study demonstrated the substantial increasing of survival time of HIV-infected patients with cryptococcal meningitis by initiated ART even in a resource limited setting (no flucytosine, local combined antiretroviral drugs with NVP based regimens).

Objectives: To define the seroepidemiology of Hepatitis B virus (HBV) infection among health care workers (HCWs) in the Institute of Neurology, and to evaluate the risk factors of HBV markers., Material and Method: Blood samples were taken from 548 HCWs for HBV profiling (HBsAg, anti-HBs and anti-HBc) by Microparticle Enzyme Immunoassay (MEIA) methods. Questionnaires of demographics, type, and duration of work, history of blood exposure, HBV vaccination, and non-occupational risks of HBV infection were interviewed., Results: Twenty-nine (5.3%) HCWs were HBsAg positive, 135 (24.6%) had anti-HBc with anti-HBs suggesting immunity acquired from a previous HBV infection, 232 (42.3%) had totally negative profiles, 40 (7.3%) had anti-HBc only, 105 (19.2%) had protective levels of anti-HBs, 7 (1.3%) had low anti-HBs levels. The significant risk factors included not having received the hepatitis B vaccine, male gender, past history of jaundice, viral hepatitis, family history of hepatoma, spouse with hepatitis B, and duration of employment in a clinical environment exceeding 5 years. No significant differences were found among HCWs regarding frequency of exposure to blood products., Conclusion: Base on the significant risk factors of hepatitis B virus infection among HCWs, these findings will help implement effective measures aimed at preventing HBV infection.

The objective of the study was to determine the predisposing factors and incidence of toxicity among AIDS patients treated with a nevirapine (NVP)-based regimen in clinical practice. A retrospective cohort study of representative samples of AIDS patients treated with a NVP-based regimen was performed. A total of 206 adult HIV/AIDS cases with median age (IQR) 33 years (range, 29-38 years), 51% male, treated between January 2004-December 2005, were included. Most (92.2%) of the patients were naïve to antiretroviral drug. The incidence of NVP toxicity was 1.09/100 person-months. The median onset time was 4 weeks post NVP initiation (2.57 weeks for skin toxicity and 12.43 weeks for hepatic toxicity). History of drug allergy and NVP toxicity were significantly associated (p = 0.006), as were sulfamethoxazole allergy and toxicity (p = 0.015). Regarding concomitant medication, concurrent anti-tuberculosis drugs significantly increased the risk of NVP associated liver toxicity (p = 0.001). Therefore, it is important to monitor adverse events from NVP, including liver function tests among HIV/AIDS patients with history of drug allergy, especially against sulfamethoxazole, and those concurrently treated with antituberculosis drugs.

The aim of this case-control study was to examine the association between periodontitis and preterm birth among non-smoking, non-alcohol drinking women. The cases were 130 women who delivered a live singleton newborn before 37 weeks gestation. A random sample of 260 women who delivered a normal child on the same day as the cases were selected as controls. Periodontal examinations were performed during 24-hour period postpartum at bedside. Other related information was collected by structured questionnaire and medical records. Multiple logistic regression analysis was performed controlling for age, ethnicity, place of residence, education, occupation, income, pre-pregnancy body mass index (BMI), weight gain, antenatal care (ANC), parity, systematic infections, genitourinary infections, antibiotics used, and history of periodontal treatment. Periodontitis (defined as presence of at least 4 teeth having > or = 1 site with a probing depth (PD) > or = 4 mm, clinical attachment loss (CAL) > or = 3 mm and bleeding on probing (BOP) after 10 seconds at the same site) was diagnosed in 33.9% of cases and 10.4% of controls. Periodontitis was significantly associated with preterm birth (adjusted OR = 4.47, 95%Cl= 2.43, 8.20). These findings suggest that periodontitis may increase the risk of preterm delivery even among women who do not smoke or drink.

A cross-sectional quantitative survey was conducted during August to November 2005 with 880 youths (16-24 years-old), including 412 males and 468 females in Nha Trang city, Vietnam. It aimed to examine the association between alcohol use and sexual behaviors by gender difference. The data revealed that the majority of respondents (65.9%) had consumed alcohol, 25.8% had sexual touching with boy/girl friends, and 10.1% of respondents had engaged in sexual experiences including vaginal sex, anal sex, and/or oral sex. Young men were significantly more likely to drink than young women were (p < 0.001), and alcohol use was significantly associated with engagement in sexual experiences (p < 0.001). There was a strong significant different between sexual touching and alcohol drinking among males (p < 0.001) and females (p < 0.001). Forty percent of young men who did not use condom in last sex and 45% of young men who had multiple sex partners were drinkers compared to 4.8% and 1.6% of non-drinkers, respectively. These significant findings will be baseline data for integrating and adapting into intervention programs for alcohol and HIV among Vietnamese youth.

Background: Maptaphut Industrial Estate (MIE) was established with a single factory in 1988, increasing to 50 by 1998. This development has resulted in undesirable impacts on the environment and the health of the people in the surrounding areas, evidenced by frequent complaints of bad odours making the people living there ill. In 1999, the Bureau of Environmental Health, Department of Health, Ministry of Public Health, conducted a study of the health status of people in Rayong Province and found a marked increase in respiratory diseases over the period 1993-1996, higher than the overall prevalence of such diseases in Thailand. However, the relationship between the pollutants and the respiratory diseases of the people in the surrounding area has still not been quantified. Therefore, this study aimed to determine the spatial distribution of respiratory disease, to estimate pollutants released from the industrial estates, and to quantify the relationship between estimated pollutants and respiratory disease in the Maptaphut Municipality., Results: Disease mapping showed a much higher risk of respiratory disease in communities adjacent to the Maptaphut Industrial Estate. Disease occurrence formed significant clusters centred on communities near the estate, relative to the weighted mean centre of chimney stacks. Analysis of the rates of respiratory disease in the communities, categorized by different concentrations of estimated pollutants, found a dose-response effect. Spatial regression analysis found that the distance between community and health providers decreased the rate of respiratory disease (p < 0.05). However, after taking into account distance, total pollutant (p < 0.05), SO2 (p < 0.05) and NOx (p < 0.05) played a role in adverse health effects during the summer. Total pollutant (p < 0.05) and NOx (p < 0.05) played a role in adverse health effects during the rainy season after taking into account distance, but during winter there was no observed relationship between pollutants and rates of respiratory disease after taking into account distance. A 12-month time-series analysis of six communities selected from the disease clusters and the areas impacted most by pollutant dispersion, found significant effects for SO2 (p < 0.05), NOx (p < 0.05), and TSP (p < 0.05) after taking into account rainfall., Conclusion: This study employed disease mapping to present the spatial distribution of disease. Excessive risk of respiratory disease, and disease clusters, were found among communities near Maptaphut Industrial Estate. Study of the relationship between estimated pollutants and the occurrence of respiratory disease found significant relationships between estimated SO2, NOx, and TSP, and the rate of respiratory disease.

A malaria epidemic warning system was established in Thailand in 1984 using graphs displaying the median or mean incidence of malaria over the previous five years compiled from malaria surveillance data throughout the country. This reporting mechanism is not timely enough to detect the occurrence of a malaria epidemic which usually occurs at the district level over a short period of time. An alternative method for early detection of a malaria epidemic employing the Poisson model has been proposed. The development of this early malaria epidemic detection model involved 3 steps: model specification, model validation and model testing. The model was based on data collected at the Vector Borne Disease Control Unit (VBDU) Level. The results of model testing reveal the model can detect increasing numbers of cases earlier, one to two weeks prior to reaching their highest peak of transmission. The system was tested using data from Kanchanaburi Province during 2000 to 2001. Results from model testing show the model may be used for monitoring the weekly malaria situation at the district level. The Poisson model was able to detect malaria early in a highly endemic province with a satisfactory level of prediction. As the application is essential for the malaria officers in monitoring of malaria epidemics, this early detection system was introduced into malaria epidemiological work. The model may be helpful in the decision making process, planning and budget allocation for the Malaria Control Program. The software for early malaria detection is currently implemented in several endemic areas throughout Thailand.

The informed consent process has become a universal requirement for research involving human subjects. Its goal is to inform volunteers regarding research in order to make decision to participate or not. This study aimed to measure volunteers' comprehension levels concerning the clinical trial and to find out factors associated with that comprehension levels. Eighty-one volunteers who enrolled in a malaria clinical trial were recruited into the study. A semi-structured questionnaire was used to collect the information. Non-participant observation was used to observe the process of informed consent. Volunteers were interviewed three days after being recruited into the trial. The results show the volunteers' comprehension was low. Only 44% of volunteers had an acceptable level of comprehension. It also revealed that 20 volunteers were not aware of being volunteers. Most volunteers knew about the benefits of participating in the trial and realized that they had the right to withdraw from the study, but not many knew about the risks of the trial. The results indicated the method of informing about the trial affected the volunteers' comprehension level. No relationship was found between comprehension level and volunteers' socio-demographic characteristics and their attitude toward the consent process. The findings from this study demonstrate volunteers who participated in the clinical trial were not truly informed. Further studies regarding enhancing volunteers' understanding of the trial are needed.

Quality control is essential for any analysis in the laboratory. The objective of this study was to prepare in vivo cow control blood samples. The experiment was performed by feeding cows with a single dose of cadmium in the form of cadmium chloride, withdrawing the blood at an appropriate time to get the highest level of cadmium and detecting the level of cadmium in the blood. It was found that feeding the cow a single dose of 0.06 mg cadmium per kg body weight resulted in the highest cadmium level of 3.622 microg/l 30-60 minutes after feeding. The samples were homogeneous because feeding the cows with single dose of cadmium let the cadmium be absorbed and distributed naturally. In addition, the samples were stable during transport. Therefore, they may be used as quality control samples to detect cadmium levels without using a lyophilized process. They could be used for proficiency testing and to evaluate whole blood analysis in the laboratory.

We investigated the charts of 381 new smear-positive tuberculosis patients at Khon Kaen Medical School during 1997-2001 using World Health Organization definitions to evaluate associations among treatment success or failure (defaulted, failed, died, or not evaluated) and tuberculosis clinic contact, demographics and clinical characteristics of the patients. Multinomial logistic regression was used for three-category outcome analysis: treatment success, transferred-out and clinical treatment failure. The treatment success and clinical treatment failure rates were 34.1% and 34.4%, respectively. About 46.5% and 85.8% of patients missed appointments at the tuberculosis clinic in the treatment success and treatment failure groups, respectively. The results show that patients who were absent from the tuberculosis clinic were 5.95 times more likely to have clinical treatment failure than treatment success, having adjusted for the effect of transfering-out and the effect of the treatment regimen and the sputum conversion status (adjusted odds ratio = 5.95; 95% CI: 2.99 to 11.84). The review showed that absence from the tuberculosis clinic was an independent risk factor for clinical treatment failure. We recommended that all new smear-positive tuberculosis patients should be followed closely at a tuberculosis clinic.

Road traffic injuries (RTIs) are increasing in developing countries where accurate routine data are usually not available. Although a capture-recapture technique has increasingly been employed in studies of human populations to provide reliable estimates of the magnitude of problems, it has rarely been used in road traffic injury research. We applied two sample capture-recapture methods using hospital and traffic police records to estimate non-fatal road traffic injuries in Thai Nguyen City during the years 2000-2004. We generated a conservative adjusted estimate of non-fatal RTIs using data from the two sources matched by name, surname, sex of victims and at least one of the other matching variables, of age, address of victim and date of injuries. We then compared the estimated rates with those reported based on police and hospital data. The results show that during years 2000-2004, the police reported 1,373 non-fatal RTIs, while hospital records revealed 6,069 non-fatal RTIs. Most reported victims on both hospital and police reports were males (67.3 % and 74.4%, respectively). More than half the victims on both hospital and police reports were drivers (77.5% and 66.1%, respectively) or pedestrians (10.6% and 7.1%, respectively). Youth and young adults (ages 15-34) constituted the majority of the victims on the hospital and police reports (52.8% and 63.7%, respectively). The capture-recapture analysis estimated that 11,140 (95% CI: 10,626-11,654) subjects were involved in RTIs during the study period. In comparison to the estimated figure, official sources accounted for only 21.9 to 60.1% of total non-fatal RTIs. Estimated rates of non-fatal RTIs were 105.5 injuries/10,000 population per year and 393 injuries/10,000 vehicles. Given the fact that under reporting of RTIs has been a major limitation of routine official data sets in developing countries, we suggested the capture-recapture method be used as a tool to provide affordable and reliable estimates of RTIs in resource-poor countries.

A prospective study was conducted at Bamrasnaradura Hospital, Nonthaburi Province, Thailand from November 11, 2002 to January 5, 2003. A total of 59 HIV/AIDS patients with interstitial infiltrates on chest radiographs were included in the study. The objectives of this study were to describe the clinical manifestations and determine the etiologies of interstitial pneumonitis, assess the short-term outcomes and determine the accuracy of the clinical diagnosis of the etiologies of interstitial pneumonitis in HIV/AIDS patients at Bamrasnaradura Hospital, Nonthaburi, Thailand. Tuberculosis was the most common diagnosis (44%), followed by Pneumocystis carinii pneumonia (25.4%), bacterial pneumonia (20.3%) and fungal pneumonia (10.2%). In tuberculosis, compared to other diagnoses, a mild cough (p = 0.031), pallor (p = 0.021), lymphadenopathy (p < 0.001), absence of skin lesions (p = 0.003), higher mean body temperature (p = 0.004) and an absence of dyspnoea on exertion (p = 0.042) were significant findings. On multivariate analysis, however, only an absence of skin lesions (p = 0.023) remained a statistically significant predictor of TB. In Pneumocystis carinii pneumonia compared to other diagnoses, dyspnea on exertion (p = 0.014), non-purulent sputum production (p = 0.047), a higher mean respiratory rate (p < 0.001), absence of lymphadenopathy (p < 0.001) and lack of purulent sputum (p = 0.030) were significant factors. By multivariate analysis, only an absence of lymphadenopathy were shown to be independently and statistically significantly associated (p = 0.040). In bacterial pneumonia, compared to other diagnoses, production of purulent sputum (p = 0.014), hemoptysis (p = 0.006), pallor (p = 0), skin lesions (p = 0.002) and a severe cough (p = 0.020) were significantly associated factors. On multivariate analysis, none of these factors were statistically significant. In fungal pneumonia, compared to other diagnoses, headache and papulonecrotic skin lesions were common findings, but no factor had a significant association. After four weeks, 59.3% of the patients were alive, 13.6% died and 27.1% were lost to follow-up. Among the alive patients 88.6% had clinically improved. On multivariate analysis, no factor was shown to be a statistically significant predictor of death. The cumulative survival after 28 days was highest among PCP patients, followed by bacterial pneumonia, tuberculosis and fungal pneumonia, but this difference was not statistically significant (p = 0.0453).

An action research design was conducted in two villages of Mueang District, Kanchanaburi Province to assess the effectiveness of a community-based approach program. Knowledge, perceived susceptibility, self-efficacy, and regular larval survey behavior were measured for program outputs. Container Index (CI), House Index (HI), and Breteau Index (BI) were used to confirm program outcomes. Key community stakeholders in the experimental village were identified and empowered through active learning in the village. Monthly meetings with the key stakeholders were used to share experiences learned, to reflect on the program outputs and outcomes as well as to plan for the next cycle of program activities. The program was quite successful. Knowledge, perception, self-efficacy, and larval survey practices in the experimental group were significantly higher than before the experiment, and higher than the comparison group. CI, HI, and BI were decreased sharply to better than the national target. Community status as community leaders was the best predictor for larval survey behavior at the first survey. Participating in the study program activities was the best predictor at the end of the program. The results from this study suggest that the dengue hemorrhagic fever (DHF) prevention and control program at the sub-district health level should be more proactive and emphasized at the village level. Monitoring the disease control program outputs and outcomes should be performed regularly during monthly meetings. Finally, local health officers need to be empowered for these matters.

The purpose of this cross-sectional study was to examine the causal relationships among age, education, family income, and stage of carcinoma, perceived benefits, perceived barriers, perceived self-efficacy, health promoting behavior and quality of life in patients with cervical cancer. Pender's Health Promotion Model (1996) provided a guide for the conceptual framework of this study. Purposive sampling was employed to recruit 488 cervical cancer patients who were undergoing radiotherapy at seven public hospitals in five areas of Thailand. The instruments used in this study included a Personal Data Form, Cognitive perception Form, Health promoting behavior scale, the social support questionnaire and The Functional Assessment of Cancer Therapy General (FACT-G) form. The proposed model was tested and modified by the LISREL Program. The modified model adequately fitted with the data. The results demonstrate that health promoting behavior had a significant direct positive effect on quality of life (beta = 0.71, p < 0.01). Cognitive perceptual factors had a significant direct effect on health promoting behaviors (P = 0.69, p < 0.01). Social support had a significant direct effect on the cognitive perceptual factors (P = 0.64, p < 0.01), health promoting behavior (beta = 0.70, p < 0.01), and the quality of life (beta = 0.48, p < 0.01). Age and education did not have a significant total effect on the quality of life. Family income had a significant direct effect on cognitive perceptual factors (beta = 0.10, p < 0.05). The stage of cancer had a significant direct negative effect on cognitive perceptual factors (beta = -0.11, p < 0.05) and the quality of life (beta = -0.12, p < 0.01). The direct effect of the predictors on the quality of life indicated that cervical cancer patients with higher practice of health promoting behavior tended to have a higher quality of life. The findings indicate that Pender's Health Promotion Model is a useful guide for explaining and predicting the health promoting behavior and the quality of life of Thai cervical cancer patients who were undergoing radiotherapy. The significance of cognitive perceptual factors and social support confirm health promoting behavior as a goal directed towards the level of well being. This has implications for health care systems in planning interventions to promote health promoting behavior in a health promotion setting in cervical cancer patients for a better quality of life and healthy. A longitudinal study and experimental study are recommended for further study.

To examine the relationship of socio-demographic characteristics, psychological factors, knowledge, attitude and behavior towards obesity among Metropolitan Waterworks Authority (MWWA) officers, a cross-sectional study was conducted between July and September, 2004. Two hundred and eighty-eight obese [body mass index (BMI) > or = 25 kg/m2] and 106 non-obese persons, aged 20-60 years, were recruited as study subjects. Data were collected by a self-administered questionnaire, comprised of three parts: socio-demographic; psychological factors (depression and stress); and knowledge, attitude, behavior related to obesity. Univariate analyses and Logistic regression models were used to study the association between obesity and possible risk factors. The results demonstrate significant associations between older age and obesity. Volunteers in the age groups of 40-49 and 50-59 years had a significantly higher risk of being obese than the age group of less than 40 years (adjusted OR = 3.4, 95% Cl = 1.1-11.1 and adjusted OR = 10.4, 95% CI = 3.3-32.7, respectively). Volunteers with unhealthy behaviors were at significantly higher risk than those with healthy behaviors (adjusted OR = 10.3, 95% CI = 2.0-52.4) while persons with moderately healthy behaviors also had increased risk, but to a lesser extent (adjusted OR = 4.5, 95% CI = 1.7-11.4). There were no associations between psychological factors and obesity in this group of volunteers. When we focused on whether they consumed more food when they were stressed, it was found that the obese consumed significantly more food during stress (p-value = 0.003). Watching television, videos, or playing computer continuously for more than 3 hours, were significantly associated with obesity. We conclude that although the obese have a good knowledge and attitude towards obesity, they still practise unhealthy behavior, have a sedentary lifestyle, and over eat when they are stressed. Future research regarding behavioral modification should be implemented at both community and country levels.

We sought to investigate the early biological effects of chlorpyrifos among 53 Thai fruit farm workers by measuring the plasma cholinesterase (PChE) and red blood cell cholinesterase (AChE) activities, a biomarker of organophosphate (OPs) pesticide during one fruit crop. The ChE activity (V(m)/K(m)) was spectrophotometrically analyzed before and after exposing to chlorpyrifos. The V(m)/K(m) values of both non-spraying and spraying seasons are found as normal distribution pattern. The median PChE and AChE activities among farm workers in the non-spraying season were 2.3 x 10(-3) s(-1) and 7.26 x 10(-5) s(-1), respectively. The median PChE and AChE activities of the farm workers in the spraying season were 2.02 x 10(-3) s(-1) and 5.95 x 10(-5) s(-1), respectively. The mean V(m)/K(m) values of PChE shifted left (t-test, p=0.013), indicating a decrease in PChE activity in the farm workers exposed to chlorpyrifos. However, the V(m)/K(m) values of AChE in nonspraying season and in the spraying season were not different (t-test, p=0.246). We propose that PChE activity can be used as a biomarker for monitoring early toxicity induced by chlorpyrifos insecticide.

A cross-sectional study was conducted to explore factors associated with the adherence of tuberculosis patients in bringing their household contacts to a TB clinic in Bangkok, Thailand. During the study period, May to December 2003, 325 sputum-smear-positive tuberculosis patients were recruited into the study. Of the 325 eligible tuberculosis patients, 169 (52.00%, 95% Cl = 47.00-57.00) brought their household contacts to the TB clinic. Psychosocial and cues to action factors were examined as indicators of the household contact screening adherence of tuberculosis patients. The results reveal that the household contact screening adherence of tuberculosis patients was significantly associated with a higher perceived susceptibility (Adjusted OR = 2.90, 95% Cl = 1.18-7.16), lower perceived barriers (Adjusted OR = 4.60, 95% CI = 1.99-10.60), a higher intention to bring the contacts to the TB clinic (Adjusted OR = 3.35, 95% Cl = 1.44-7.76), and a short distance from home to the TB clinic (Adjusted OR = 11.47, 95% Cl = 4.57-28.79). The results from this study provide information for TB clinic staff for developing an appropriate intervention program. Through effective intervention and active policy enforcement, a higher percentage of household contact screening adherences can be achieved.

The occurrence of malaria epidemics in Thailand was reviewed from the malaria surveillance report of the National Malaria Control Program. The literature review revealed that the four epidemic periods recorded during 1980-2000 almost always occurred in the provinces and districts located along international borders. Malaria epidemics are caused by various factors such as: extensive population movement, multi-drug resistance development, low immune status of the population, lack of knowledge and appropriate personal protection against mosquito biting, and the re-emergence of malaria transmission in low malarious areas. Such factors can lead to changes in the parasite ratio and appearance of malaria epidemics throughout the country. Evidence related to the burden of malaria epidemics was also reviewed to identify causal factors that will be helpful in future research.

A cross-sectional study was conducted to determine the association between environmental factors and tuberculosis infection among household contacts aged less than 15 years in Bangkok, Thailand, between May and December 2003. During the study period, 480 household contacts aged under 15 years were identified. The prevalence of tuberculosis infection among household contacts was 47.08% (95% CI = 42.60-51.56). A generalized estimating equation (GEE) indicated that the risk of positive tuberculin skin testing in household contacst was found to increase with household crowding. Children living in a crowded household were five times more likely to have tuberculosis infection (OR = 5.19, 95% CI = 2.65-8.69). The association between environmental factors and tuberculosis infection assists community tuberculosis staff in understanding the risks for tuberculosis infection in the community and planning appropriate preventive actions based on this risk.

The aim of this study was to examine the effects of age, time period, and birth cohorts with dengue fever/dengue hemorrhagic fever (DF/DHF) in Bangkok, Thailand over the period 1981-2000. The age group at greatest risk for DF/DHF was 5-9 years old. The period effect shows a remittent pattern, with significant increases in 1986-1990 and 1996-2000. The birth cohort group showed a significant decreasing trend from the 1961-1965 group to the 1991-1995 group (R2 = 0.7620) with a decreasing rate of 0.1. We concluded that the temporal trend of DF/DHF is decreasing; especially for DHF.

Leprosy which has caused stigma and social ostracism for millennium is nearing elimination worldwide as a public health problem, but the leprosy burden in Nepal is still 4.4 times greater than WHO's target level of less than one case per 10,000 population. Although leprosy affects both the sexes, in most parts of the world males are affected more than females at a ratio of 2:1. The general objective of the study was to investigate the gender difference in socio-epidemiological factors for leprosy. The analytic cross-sectional study was carried out in one of the most hyper endemic district- Dhanusa district of Nepal. Stratified random sampling method was applied for the selection of the patients. Chi-square/Fisher's exact test was applied to assess statistically significant differences in values between males and females. There were 580 leprosy patients (385 male and 195 female) aged above 15 years registered for multi drug therapy between April 1, 2001 to March 31,2002 in the 16 main health centers of the district. Out of 580 patients, 273 patients (183 males and 90 females) were included in the study in order to collect the data on socio-demographics, patient's knowledge on leprosy, treatment seeking behaviour, and social problems faced by the patients. Data were collected using a structured interview schedule. The mean age of the male patients was 45.1 years (range 15-77 years) and female patients were 40.3 years (range 15-75 years). Among male patients 93.4% were married while among female patients 70.0% were married. Among male patients 51.9% were illiterate whereas 71.1% were illiterate among female patients. Most of the patients (69.6%) lived in joint family and the rest in nuclear family. Among male patients, 86.9% had good knowledge about the disease compared to 73.3% among females. This study showed that among the female patients 12.2% were facing high level of social problems, while among male patients only 4.4% were facing the same. About 15% patients had poor treatment seeking behaviors (8.2% among males and 27.8% among females). A significant gender differences among leprosy patients have been found in age distribution, educational status, marital status, caste types, family members, and overall knowledge on the general aspect of leprosy, social problems faced by the patients and treatment seeking behaviour.

This study describes the development of Cryptosporidium parvum in MDCK, MA-104, Hep-2 and Vero cell lines. Differences in susceptibility, infectivity, and the methodology of excystation were determined. Various solutions were considered to determine the factors which enhanced the excystation (eg with and without sodium hypochlorite, trypsin or sodium taurocholate). It was shown that the sporozoites could be excysted in media either with or without trypsin and sodium taurocholate, but the number of sporozoites in the latter solution was less than the former one. Only oocysts digested by sodium hypochlorite and trypsin can enter the culture cells. Numerous meronts and oocysts were demonstrated and persisted for 9 days. Asexual stages were not observed in MA-104. Only few oocysts could be detected 1-3 days post-inoculation. There was a significant difference between the number of oocysts, which invaded MDCK, MA-104, and Hep-2 cells. MDCK gave the highest susceptibility to oocyst invasion among the three cell lines and asexual stages were also found. Among the 25 isolates, which had been cultivated, 23 isolates could infect MDCK and Hep-2. Only 2 isolates could not infect the MDCK cell. These 2 isolates could infect the Vero cell and yielded high numbers of trophozoites. Praziquantel (PZQ), doxycycline, and paromomycin (PRM) were tested on the infecting parasites. The drugs were added either with the inoculum or 24 hours after inoculation. None of them was effective, including PRM, which had been previously reported as effective.

This research aimed to determine if less invasive biological specimens (other than blood), such as feces and clipped toenails could be used to determine manganese concentrations among occupationally exposed human subjects. In addition to blood samples, which have routinely been used in determining manganese concentration, specimens were collected from welders working at the Electricity Generating Authority of Thailand, Mae Moh Thermal Power Plant, Lampang Province. Manganese concentrations in these three biological samples were determined by atomic absorption spectrophotometer. Correlations of manganese concentrations among these three biological samples were measured, and found to be rather poor (Pearson's r <+/-0.2, p > 0.1 for any pair-wise comparisons). Blood remains the recommended material for biomonitoring manganese concentrations in occupationally exposed subjects.

Background: Some candidate HIV-1 vaccines may not prevent HIV-1 infection but may alter the course of disease. Surrogate endpoints based on early laboratory makers in HIV-1-infected persons who are antiretroviral therapy (ART)-naive will be useful for evaluating vaccine efficacy in slowing disease progression (VEp). We examined pretreatment HIV-1 viral loads and CD4 cell counts in recent HIV-1 seroconverters to inform selection of these endpoints., Methods: We studied 130 newly HIV-1-infected injection drug users identified from a prospective cohort of initially uninfected persons in Bangkok during 1995 through 1998. We analyzed trends in HIV-1 viral loads and CD4 cell counts as well as progression to the surrogate endpoint, defined as 2 consecutive CD4 cell counts of fewer than 350 cells/mm, during 24 months after the first HIV-1 seropositive (FP) visit., Results: Median HIV-1 RNA copies/mL with interquartile ranges were 43,693 (14,320-94,767) at the FP visit, 46,924 (16,273-104,314) at 6 months, 28,446 (11,292-54,325) at 12 months, and 18,080 (8713-54,059) at 18 months. HIV-1 viral loads at the FP visit and at 18 months were positively correlated (r = 0.53, P < 0.0001). Of 130 participants, 12% reached the surrogate endpoint by 6 months, 16% by 12 months, and 27% by 18 months. In Cox regression analyses, HIV-1 viral loads of more than 50,000 copies/mL at the FP visit (hazard ratio [HR] = 2.3, 95% confidence interval [CI]: 1.1-4.8) and first CD4 cell count of 500 or fewer cells/mm (HR = 7.6, 95% CI: 3.2-17.6) were independently associated with faster progression to the surrogate endpoint., Conclusions: Participants with high HIV-1 RNA levels and low CD4 cell counts close to the time of seroconversion were more likely to experience early immunologic progression. Approximately one quarter of seroconverters reached the surrogate immunologic endpoint within 18 months of their FP visit and before starting ART, suggesting the utility of this endpoint for analyses of VEp in some ongoing and planned HIV-1 vaccine efficacy trials.

The introduction of multidrug therapy (MDT), recommended by WHO, has been a major advance in the treatment of leprosy because of its relatively short treatment course and low rate of relapse. Although leprosy treatment is provided to both sexes equally, in most parts of the world significant differences have been found in treatment status. The main objective of the study was to investigate gender differences in epidemiological factors associated with treatment status of leprosy patients. An analytic cross-sectional study was carried out in the most hyperendemic Dhanusa District, Nepal. Stratified random sampling was applied for selection of the patients. Statistical analysis of the differences in treatment status, between males and females, and among other epidemiological factors of interest was carried out using multiple logistic regression. Chi-square/Fisher's exact test were also used to assess significant differences in values between males and females. There were 580 leprosy patients (385 male and 195 female) aged >15 years registered for MDT between April 1, 2001 to March 31, 2002 in the 16 main health centers of the district. Of the 580 patients, a total of 273 (183 male and 90 female) were included in the study, to collect data on clinical type of leprosy, patterns of physical deformity/disability, site of skin lesions, and socio-demographic information. There were 183 male (68.3% on MB-MDT) and 90 female (61.1% MB-MDT) leprosy patients. We found that 79.2% of male patients completed treatment, while 34.4% female patients did not complete within the given time frame. Significant gender differences among leprosy patients were found in the distribution of disability grades and treatment completion status. However, there was no significant gender difference in the distribution of leprosy types and skin lesion sites. The study also found significant associations between treatment completion status and gender (adjusted OR 2.05, 95% CI: 1.07-3.94), educational status (adjusted OR 2.37, 95% CI: 1.12-4.99), disability grade I (adjusted OR 3.14, 95% CI: 1.23-8.04), and disability grade 0 (adjusted OR 2.92, 95% CI: 1.14-7.47) after adjustment for all other leprosy/demographic factors.

A cross-sectional study was conducted to determine the prevalence of tuberculosis infection and risk factors for tuberculosis infection among household contacts aged less than 15 years in Bangkok, Thailand, between August 2002 and September 2003. During the study period, 342 index cases with sputum smear positive pulmonary tuberculosis patients were recruited into the study and their 500 household contacts aged under 15 years were identified. The prevalence of tuberculosis infection among household contacts was found to be 47.80% (95%CI = 43.41-52.19). In multivariate analysis, a generalized estimating equation (GEE) was used to determine the risk factors for tuberculosis infection among household contacts. The results indicated that the risk of tuberculosis infection was significantly associated with close contact (adjusted OR = 3.31, 95%CI = 1.46-7.45), exposure to female index case (adjusted OR = 2.75, 95%CI = 1.25-6.08), exposure to mother with tuberculosis (adjusted OR = 3.82, 95%CI = 1.44-10.14), exposure to father with tuberculosis (adjusted OR = 2.55, 95%CI = 1.19-5.46), exposure to index case with cavitation on chest radiograph (adjusted OR = 4.43, 95%CI = 2.43-8.05), exposure to index case with 3+ sputum smear grade (adjusted OR = 3.85, 95%CI = 1.92-7.70), and living in crowded household (adjusted OR = 2.63, 95%CI = 1.18-5.85). The distribution of tuberculosis infection and risk factors among contact cases are significant for health care staff in strengthening and implementing tuberculosis control programs in Thailand.

We investigated the association of HLA-DRB1, -DQA1 and -DQB1 alleles and haplotypes in 33 Thai HIV discordant couples. A significantly lower frequencies of DRB1*14 (3.0% vs 11.3%, p = 0.048) and DQA1*0103 (0.0% vs 5.63%, p = 0.042) alleles were found in the seropositive individuals when compared with HIV-negative controls. In contrast, there was no significant difference in HLA-DQB1* allele frequencies. The haplotype analysis revealed that DRB1*1501-DQA1*0102-DQB1*0601 (7.6% vs 0.0%, p = 0.002), DRB1*0405-DQA1*0302-DQB1*0401 (7.6% vs 1.3%, p = 0.024) and DRB1*1401-DQA1*0104-DQB1*05031 (6.1% vs 0.0%, p = 0.007) were found to be significantly higher frequencies when compared between HIV seronegative partners and HIV negative controls, but DRB1*1501-DQA1*0102-DQB1*0502 (0.0% vs 8.1%, p = 0.01) was significantly lower. The DRB1*1602-DQA1*0101-DQB1*0502 (4.6% vs 0.0%, p = 0.024) haplotype was found to be significantly higher frequencies in HIV seropositive individuals when compared to HIV negative controls but the DRB1*1502-DQA1*0101-DQB1*0501 (1.5% vs 8.1%, p = 0.049) haplotype was lower.

This descriptive cross-sectional study was conducted to investigate gender differences in the epidemiological factors associated with the treatment seeking behaviors of TB cases in the rural communities of Bangladesh. The study reveals that there is significant gender difference in treatment seeking behaviors of rural TB cases and the majority of them (52%) have taken prior treatment from various traditional healers, 70% of them are females who attended health centers (UZHCs) as the other choice (adjusted OR: 4.2, 95% CI: 2.0-8.4). It was found that the mean patient delay was 63 days (range 14-210 days) where half of the females delayed more than 60 days while they were spreading their disease. The study findings reveal gender differences in treatment seeking behaviors associated with socio-cultural barriers, particularly among females in their access to TB care. Fifty-five percent of cases wanted the diagnosis of TB remain confidential to avoid being labeled as TB patients, where 82.7% were female, 85.6% of female TB patients had problems in their relationships with their spouse (61%) and family members (58%) after being diagnosed with TB. The results of the TB service factors found that 39% of females were not satisfied with their provider's behaviors, which was significantly associated with treatment seeking behavior (adjusted OR: 2.6, 95% CI: 1.0-6.6). The study findings strongly suggest that there was a significant gender difference in treatment seeking behavior in rural Bangladesh. Based on the study findings, we recommend developing an appropriate gender strategy for developing a TB control program, comprised of operational, socio-cultural and community awareness interventions aimed at treating undiscovered reservoirs of female TB cases in rural Bangladesh.

Humans are thought to acquire Toxoplasma infection by three major routes: ingesting food and water contaminated with oocysts from cat excreta, consumption of under-cooked infected meat, and transplacental transfer. Congenital clinical toxoplasmosis in the newborn indicating definite transplacental transmission had been reported in Thailand, whilst studies concerning infection due to the other two routes were inconclusive. Since the way domestic cats live and eat and also the eating behavior of Thai people differ from those in the West, we conducted a sero-epidemiological study of T. gondii in cats and their owners in Bangkok metropolitan area. Among 327 humans, the prevalence of Toxoplasma antibody was 6.4% and in 315 cats it was 7.3%. These relatively low prevalence rates may result from the predominantly well-cooked fish and rice diet of stray cats, which congregate in temples where they are fed. Toxoplasma antibody seropositive was associated with living in close proximity to seropositivity cats [OR (95% CI) = 5.43 (1.28-23.04); p=0.01]. Risks were increased in and around temples, particularly if courtyards were of earth or grass, suggesting ground temperature was an important determinant of oocyst survival.

The intercountry border areas of Thailand have high malaria receptivity and vulnerability that present numerous problems in the control of malaria transmission. This study focused on the 30 provinces of Thailand situated next to neighboring countries, which can be divided into 4 groups: the Thai-Myanmar border (10 provinces), the Thai-Cambodia border (6 provinces), the Thai-Lao border (10 provinces) and the Thai-Malaysia border (4 provinces). The purpose of the present study was to describe the pattern and trend of malaria incidence in the highly endemic provinces along the Thai borders for the 11 years from 1991 to 2001. Analysis of trends showed the distribution of malaria parasites to have shifted from a preponderance of Plasmodium falciparum to Plasmodium vivax along the western border with Myanmar, the northern border with Lao PDR and along the eastern border with Cambodia whereas the southern border with Malaysia the pattern changed from a preponderance of P. vivax to P. falciparum, since 1997. There was a significant difference in annual parasite incidence between borders and non-border districts, especially along the Thai-Myanmar and Thai-Cambodia borders. It is thus evident that all border districts should pay more attention to control of malaria transmission and the activities of the malaria surveillance system, and that monitoring and evaluation of the Thai Malaria Control Program needs to be performed consistently, including some areas where a few malaria cases were found as well as in malaria free areas.

Since having health insurance cannot guarantee access to care among the insured persons, their actual health seeking behavior should be evidence reflecting true access. Therefore, the study aimed to present the patterns of health seeking behavior among the insured persons who actually were able to get free services from their registered hospitals under the Social Security Scheme. Purposive sampling was done of 1,003 insured persons who were willing to participate in the study from small, medium and large establishments in the Huai Khwang district in Bangkok. A health diary was employed as one of the data collecting tools with a follow-up period of six months. The average illness rate found was 6.44 episodes/person/year. The characteristics of illnesses reported were described in terms of symptom groups, perceived severity, duration, work or non-work related cause. No treatment or self care, seeking help from non-registered health facilities and seeking help from registered hospitals and clinics were the patterns of health seeking behaviors found in the study. The patterns of health seeking behaviors among the participants varied depending on the stage of treatment, perceived severity of illness and types of additional health benefits. Seeking care from registered hospitals and clinics was found among the illnesses with a higher level of perceived severity, among the participants with chronic diseases, and among the illnesses that were treated with higher stages. Therefore, health insurance might not be able to guarantee true access to needed care for people unless the comprehensive health care provider networks are designed to cover more types of services, be more convenient and have more accessible health care providers.

To search for evidence of a protective role of the CD23/NO pathway against cerebral malaria, concentrations of reactive nitrogen intermediates (RNI) and sCD21, total immunoglobulin (Ig)E and sCD23 were compared between 17 cases of cerebral malaria and 33 controls. The geometric mean of sCD23 concentration was higher among cerebral malaria cases than among controls (optical density 2643/1495, P = 0.01). The ratio between sCD21 and sCD23 was significantly lower in cerebral malaria cases than in controls (0.67 +/- 0.02 versus 0.77 +/- 0.02, respectively, P = 0.009). Multiple linear regression analysis showed that, among cerebral malaria cases, there was a clear correlation between RNI and both IgE (P = 0.007) and sCD21 (P < 0.0001). Among controls, there was a strong negative correlation between RNI and sCD23 concentrations (r = -0.61, P < 0.0001). However, multivariate analysis unmasked the fact that, in controls, there was also a positive correlation between RNI and IgE (P = 0.045). Logistic regression showed that increased RNI concentrations were associated with a cerebral malaria adjusted odds ratio of 1.05 per unit increase [95% confidence interval (CI) 1.006-1.1, P = 0.02] and that an increased ratio between sCD21 and sCD23 was associated with protection from cerebral malaria (adjusted OR = 0.00001 per unit increase (95% CI 0-0.03, P = 0.005). These different immunological profiles suggest that, among controls, the CD23/NO pathway was chronically stimulated whereas, in cerebral malaria, its stimulation was acute, which could explain why some patients developed cerebral malaria and others did not.

Eosinophilic meningoencephalitis (EME) remains an important neurological disease and is widely distributed in Thailand. We analyzed the cytological specimens of 56 EME cases. Pertinent clinical data were analyzed retrospectively and correlated with the cerebrospinal fluid (CSF)analysis. Headache was the commonest symptom seen in all EME cases. History of raw or partially cooked Pila snail ingestion was elicited from most patients. There was a marked seasonal occurrence between July to January. Patients received specific treatment as supportive therapy, which included spinal taps, analgesics and corticosteroids, was adequate. No fatal cases were seen. The CSF specimens were sorted into two categories: fresh CSF and hematoxylin and eosin (H&E) stained centrifuged CSF sediment. There was a statistically significant difference between the number of eosinophils and lymphocytes of fresh CSF and the H&E stained centrifuged CSF sediment (p = 0.001 and 0.001 respectively). The CSF glucose and the number of eosinophils in both methods were significantly correlated (p = 0.000, p = 0.008 for fresh CSF and the H&E stained centrifuged CSF sediment respectively). Moreover, the number of eosinophils was statistically significant with the protein in the CSF (p = 0.013), and intracranial pressure (ICP) (p = 0.025). Higher yields of eosinophils, especially in the early course of the disease, can readily be detected in the H&E stained centrifuged CSF sediment, whereas fresh specimens were negative. Further tests may increase the sensitivity and specificity of EME diagnostic results.

A randomized, double-blind, placebo-controlled phase I/II study of AIDSVAX (MN) was conducted among injecting drug users in Bangkok, Thailand. Four doses of vaccine (300 microg of MN-rgp120 in alum) or placebo (alum) were given at study entry and at 1, 6, and 12 months. The objectives of the study were to evaluate (1) the feasibility of conducting vaccine trials in this population; (2) the safety of this candidate AIDS vaccine; and (3) the immunogenicity of this vaccine. Thirty-three volunteers (22 vaccine and 11 placebo recipients) were recruited. None were lost to follow-up during the 18-month study. Mild reactogenicity was noted, which was similar in both vaccine and placebo recipients. The vaccine induced anti-HIV-1 antibody in all vaccine recipients. Maximal titers of binding antibodies of MN-rgp120 and the V3 domain of MN-rgp120 were induced after the third (6 month) dose while maximal neutralizing antibodies followed the fourth (12 month) dose. The vaccine-induced antibodies from several volunteers were capable of neutralizing macrophage-tropic, subtype B viruses (301660 and JRCSF) detected in a PBMC-based assay. Binding and neutralizing antibodies declined about 10-fold in the 6 months after the last boost. Two vaccinees became infected during the trial, both with subtype E viruses. A phase III efficacy trial, using a bivalent gp120 vaccine containing antigens from a subtype B virus (MN) and a subtype E virus (A244), was initiated in March 1999 in injecting drug users in Bangkok.

Background: Two HIV-1 envelope subtypes have accounted for virtually all infections in Thailand: subtype B' (Thai B), found mainly in injection drug users (IDU), and subtype E, found in over 90% of sexually infected persons and an increasing proportion of IDU in recent years. It remains unclear whether there are differences in pathogenesis associated with these HIV-1 subtypes., Methods: From November 1993 to June 1996, demographic, risk, clinical, and laboratory data were collected by enhanced surveillance from HIV-infected inpatients (> or =14 years) at an infectious disease hospital near Bangkok. HIV-1 subtype was determined by V3-loop peptide enzyme immunoassay (EIA). Because of confounding, multivariate analyses were stratified by risk category and controlled for sex and age., Results: The infecting HIV-1 subtype was determined for 2104 (94.9%) of 2217 HIV-infected patients with complete data: 284 (13.5%) were subtype B', 1820 (86.5%) were E. Specimens from 113 (5.1%) patients were non-reactive or dually reactive on peptide EIA and were excluded. Among IDU, 199 (67.2%) had subtype B', and 97 (32.7%) had E. IDU accounted for 70.1% (199/284) of patients with subtype B' and 5.3% (97/1820) of those with E. Patients infected with HIV-1 subtypes B' or E had similar spectrums of opportunistic infections (OI), levels of immunosuppression, and in-hospital mortality rates. Of patients who did not inject drugs, more patients infected with subtype E had extrapulmonary cryptococcosis than those with subtype B' (adjusted odds ratio, 2.6; 95% confidence interval, 1.28-5.37)., Conclusion: HIV-1 subtypes B' and E seem to be associated with similar degrees of immunosuppression and, with one exception, with similar OI patterns. These data do not suggest an association between HIV-1 subtype and differences in pathogenicity.

Objective: To characterize the clinical spectrum of disease and immune status of adult HIV-1-infected patients in Bangkok., Design: Cross-sectional survey of hospital admissions., Methods: From November 1993 through June 1996, demographic, clinical, and laboratory data were collected from HIV-infected inpatients (> or =14 years old) at an infectious diseases hospital., Results: Of 16,717 persons admitted, 3112 (18.6%) were HIV-seropositive, 2261 of whom were admitted for the first time. Of 2261, 1926 (85.2%) were male, 1942 (85.9%) had been infected heterosexually or by means not related to drug use, 319 (14.1%) were injection drug users (IDUs), and 1553 (68.7%) had AIDS. The most common AIDS-defining conditions were extrapulmonary cryptococcosis (EPC; 38.4%), tuberculosis (TB; 37.4%), and wasting syndrome (WS; 8.1%). IDUs were more likely (p < .05) to have TB or WS but less likely (p < .05) to have EPC or Pneumocystis carinii pneumonia than patients with no history of injection drug use. Lymphocyte counts were measured for 2047 (90.5%) patients; 81.8% had < or =1500 lymphocytes/microl., Conclusion: These HIV-infected patients were admitted with severe immunosuppression. Cryptococcosis and TB are major problems and differ in prevalence among IDUs and persons infected sexually. Clinical and immunologic information is critical in improving the lives of HIV-infected persons in Asia through prevention, treatment, and prophylaxis.

Objectives: To determine the incidence of HIV-1 infection, temporal trends in incidence, and risk factors for seroconversion in a cohort of female commercial sex workers (CSW) in upper northern Thailand, the region of Thailand with the highest rates of HIV-1 infection., Methods: CSW were enrolled from 1991 through 1994 and evaluated prospectively with interviews, physical examination, testing for sexually transmitted diseases (STD), and serologic testing for HIV-1 infection., Results: The incidence of HIV-1 seroconversion in the first year of follow-up was 20.3 per 100 person-years among 126 brothel-based CSW and 0.7 per 100 person-years among 159 other CSW who worked in other venues such as bars or massage parlors. Incidence remained elevated among brothel-based CSW who were enrolled later in the study compared with those who enrolled earlier. Through 1996, 30 women seroconverted. In a multivariable proportional hazards model, seroconversion was significantly associated (P < 0.05) with brothel-based sex work (adjusted risk ratio, 7.3) and Chlamydia trachomatis cervical infection (adjusted risk ratio, 3.3)., Conclusion: Despite national HIV control efforts and declining rates of infection among young men in Thailand, brothel-based CSW may continue to be at high risk for HIV-1 infection. Additional efforts are needed to provide alternative economic choices for young women, to ensure universal condom use during commercial sex, and to develop new prevention technologies.

The objective of this study was to assess changes in the family situation of HIV-infected women who have recently given birth. As part of a prospective perinatal HIV transmission study, interviews were conducted with a subset of HIV-infected women at 18 to 24 months postpartum, and answers were compared with baseline information obtained during pregnancy. Standardized scales were used to assess levels of psychosocial functioning. A convenience sample of 129 HIV-infected women enrolled during pregnancy was interviewed at 18 to 24 months postpartum. At delivery, the women were young (median age, 22 years), primiparous (57%), and asymptomatic (93%). When baseline and follow-up data were compared, more women were living alone (1% versus 6%; p = 0.03), fewer women were living with their partners (98% versus 73%; p < 0.001), and 30% of families had reduced incomes. At follow-up, 10% of partners had died, and more partners than wives had become ill or died (21% versus 4%; p = 0.02). Most children (78%) were living with their mothers, but only 57% of the HIV-infected women were the primary caretakers. Fewer women had disclosed their HIV status to others (e.g., family, friends) than to their partners (34% versus 84%; p < 0.001), largely because of fear of disclosure. The women appeared to have high levels of depression and worry. The women's greatest worries were about their children's health and the family's future. Within 2 years after childbirth, substantial change within the families of HIV-infected women was evident. These were manifest by partner illness or death, family separation, reduced family income, shifting responsibilities for child care, and signs of depression and isolation. Providing family support is a major challenge in Thailand as the perinatal HIV epidemic progresses.

Objectives: To determine HIV seroprevalence and incidence among various blood donor types, and to estimate the rate of window-period blood donations., Design: Retrospective cohort from computerized donor records., Methods: Records were analysed from all 60,483 donors (contributing 97,464 donor units) at a public university teaching hospital blood bank in Bangkok, Thailand, from 1 January 1990 to 30 June 1993. Annual HIV incidence among 14,482 repeat donors who were HIV-seronegative on their first donation was calculated assuming equal probability of seroconversion between last seronegative and first seropositive donations. To estimate the probability of window-period donations, we assumed that the time from HIV infectivity to onset of detectable antibody was 45 days., Results: In 1990, HIV incidence calculated for all repeat donors was 307 per 100,000 person-years; the probability of a window-period donation was 38 in 100,000 donations or one in 2644 donations. During 1991-1993, this probability decreased by one-half. However, one-time donors were more than twice as likely as repeat donors to be HIV-1-seropositive., Conclusions: The rate of HIV window-period blood donations among Thai repeat donors was relatively high compared with that in developed countries and was probably even higher among one-time donors. Improved donor deferral criteria are needed in Thailand.

Survival from the time of AIDS diagnosis to death was determined retrospectively among Thai patients (> or = 13 years old) who attended a public tertiary care infectious disease hospital in a suburb of Bangkok, Thailand, from February 1987 through February 1993. An AIDS diagnosis was based on the 1987 Centers for Disease Control (CDC) definition, except Penicillium marneffei infection was included as an AIDS-defining condition. Of 329 AIDS patients, 152 (46.2%) had died. The median age at diagnosis was 31.5 years (range, 18-74) 306 patients (93.0%) were males. Reported risk categories were heterosexual contact (55.2%), injecting drug use (IDU, 22.6%), male homosexual or bisexual contact (9.5%), and unidentified risk or other (12.7%). Median survival time (Kaplan-Meier) for all patients was 7.0 months; 1-year survival probability was 39.2% (95% confidence interval [CI] = 31.5-46.9%). Cox's proportional hazards model showed three factors associated with survival: age, reported risk category, and presenting diagnosis. Patients aged 26 to 35 years survived longer (median survival time, 10.6 months; relative hazard [RH] = 0.61, 95% CI = 0.44-0.85, referent: others), as did patients in sexual risk categories (median survival time, 7.3 months; RH = 0.59, 95% CI = 0.40-0.78, referent: IDU and other categories). A single presenting diagnosis of extrapulmonary tuberculosis was also associated with longer survival (median survival time, 19.9 months, RH = 0.55, 95% CI = 0.35-0.86, referent: other diagnoses). AIDS patients in the early phase of the epidemic in Bangkok have much shorter survival times than patients in developed countries, in part perhaps because they are often diagnosed late in the course of HIV infection. Increased attention should be given to the early diagnosis and treatment of these patients.

Objective: To measure trends in the incidence of HIV-1 infection among drug users in treatment at Thailand's largest drug detoxification unit., Design: A retrospective cohort was established using computed, existing HIV-1 test results of 26,396 inpatients and outpatients admitted for 47,907 drug detoxification treatment courses from August 1987 to August 1992., Methods: Matching of patient record numbers showed that 10,050 (38.1%) patients had been admitted two or more times during the period. From these, we selected a cohort of 7807 initially HIV-negative patients. Subsequent seroconversions among them were assumed to have occurred with uniform probability throughout the interval between the last HIV-negative and the first HIV-positive tests., Results: There were 2311 (29.6%) seroconversions in the cohort. HIV-1 incidence among the 5974 (76.5%) who were injecting drug users (IDU) escalated from 20 new infections per 100 person-years (PY) of observation in 1987 to a peak of 57 per 100 PY in 1988, then gradually declining to a stable rate of about 11 per 100 PY during 1991 and 1992. Non-IDU (smokers, inhalers) constituted 683 (8.8%) of the cohort patients, and had HIV-1 incidence rates varying from 0.2 to five per 100 PY. 'Mixed' drug users, defined as individuals reporting different routes of drug administration on different admissions, composed 1150 (14.7%) of cohort patients and had an HIV-1 incidence rate between that of IDU and non-IDU. Prevalence of HIV-1 seropositivity among all IDU increased rapidly, from about 1% in early 1988 to a peak of about 40% by early 1989, and has remained stable through 1992., Conclusions: Prevention efforts must continue for IDU, since recent annual HIV-1 incidence remains high at > 10 per 100 PY. Such a high rate suggests that this group should be considered for HIV-1 vaccine efficacy trials. Stable HIV-1 prevalence can mask substantial incidence in a population with high turnover.