Chatporn Kittitrakul

Risk of potentially rabid animal exposure among foreign travelers in Southeast Asia.

Background Each year millions of travelers visit Southeast Asia where rabies is still prevalent. This study aimed to assess the risk of rabies exposure, i.e., by being bitten or licked by an animal, among travelers in Southeast Asia. The secondary objective was to assess their attitudes and practices related to rabies. Methodology/Principal Findings Foreign travelers departing to the destination outside Southeast Asia were invited to fill out the study questionnaire in the departure hall of Bangkok International Airport. They were asked about their demographic profile, travel characteristics, pre-travel health preparations, their possible exposure and their practices related to rabies during this trip. From June 2010 to February 2011, 7,681 completed questionnaires were collected. Sixty-two percent of the travelers were male, and the median age was 32 years. 34.0% of the participants were from Western/Central Europe, while 32.1% were from East Asia. Up to 59.3% had sought health information before this trip. Travel clinics were the source of information for 23.6% of travelers. Overall, only 11.6% of the participants had completed their rabies pre-exposure prophylaxis, and 15.3% had received only 1–2 shots, while 73.1% had not been vaccinated at all. In this study, the risk of being bitten was 1.11 per 100 travelers per month and the risk of being licked was 3.12 per 100 travelers per month. Among those who were bitten, only 37.1% went to the hospital to get post exposure treatment. Travelers with East Asian nationalities and longer duration of stay were significantly related to higher risk of animal exposure. Reason for travel was not related to the risk of animal exposure. Conclusions Travelers were at risk of being exposed to potentially rabid animals while traveling in Southeast Asia. Many were inadequately informed and unprepared for this life-threatening risk. Rabies prevention advice should be included in every pre-travel visit.

Incidence and Spectrum of Health Problems Among Travelers to Laos

BACKGROUND The number of travelers visiting Laos has more than doubled in the last 5 years. Little is known about their pre-travel preparations and the incidence of health problems during their trips. METHODS At three border posts between Laos and Thailand, travelers were invited to complete a study questionnaire. They were asked about their demographic profile, travel characteristics, pre-travel health preparations, and health problems during their stay in Laos. RESULTS From September 2011 to April 2012, 1,205 questionnaires from Thais and 1,191 from foreigners were collected. Approximately 60% of the travelers were male; the overall median age among the Thais was 43 years, and among the foreigners was 32 years. Most foreign visitors were from Europe (66.8%), followed by other Asian countries (19.0%) and North America (7.1%). Almost half of the foreigners (47.8%) traveled as individual backpackers, whereas the majority of Thais traveled as package tourists. Foreigners were more likely to trek, cycle, and swim during their trips. There were also significant differences in the average length of stay between foreigners (16.1 days) and Thais (3.8 days, p < 0.001). Health problems were reported in 24.9% of foreigners, the most common being diarrhea, cough, animal exposure, and fever. Only 6.1% of Thais reported health problems, the most common being cough and diarrhea. The relative risk adjusted for duration of stay was 1.63 (95% confidence interval: 1.01-2.64). Occurrence of health problems was associated with younger age group, non-Asian nationality, length of stay, and participation in adventurous activities. CONCLUSIONS Health problems are rather frequent among non-Thai travelers in contrast to Thais during their trips to Lao Peoples Democratic Republic. There were significant differences in terms of risk profile and prevalence of health problems between these two groups.

Clinical Trial of an Oral Live Shigella sonnei Vaccine Candidate, WRSS1, in Thai Adults

ABSTRACT Live attenuated Shigella sonnei vaccine candidate WRSS1, previously tested in U.S. and Israeli volunteers, was evaluated in a population of adult Thai volunteers in which the organism is endemic. In a randomized placebo-controlled, double-blind design, inpatient participants received a single oral dose of 1.6 × 104 CFU of WRSS1. The vaccine was generally well tolerated, with equal numbers of vaccinees and placebo controls showing mild symptoms. Only 3 of 13 vaccinees (23%) had culture-positive stools, while a total of 9 vaccinees were positive by PCR. Lack of vaccine shedding in volunteers correlated with lack of clinical symptoms and immune responses, just as the duration of fecal shedding correlated directly with stronger immune responses. Two months following immunization, 10 vaccinees and 10 newly recruited naive controls received a challenge dose of 1,670 CFU of virulent S. sonnei strain 53G. This dose had previously demonstrated a 75% attack rate for dysentery in Thai volunteers. However, in this study the attack rate for dysentery in naive controls after challenge was 20%. Based on clinical record summaries, 3 vaccinees and 5 naive controls experienced clinically relevant illness (diarrhea/dysentery/fever/shigellosis), and a 40% vaccine efficacy was calculated. When these data are compared to those for the performance of this vaccine candidate in more naive populations, it is clear that a single oral dose of WRSS1 at 104 CFU failed to achieve its full potential in a population in which the organism is endemic. Higher doses and/or repeated immunizations may contribute to improved vaccine shedding and consequent elevation of protective immune responses in a population in which the organism is endemic. (The study has been registered at ClinicalTrials.gov under registration no. NCT01080716.)

Burden of Liver Abscess and Survival Risk Score in Thailand: A Population-Based Study

In Thailand, the burden of liver abscess, a life-threatening infectious disease, has not been thoroughly evaluated. We developed a predictive scoring system to estimate survival of patients with liver abscess using information from the 2008-2013 Nationwide Hospital Admission Data to evaluate the burden of liver abscess in Thailand. All patients with primary diagnosis of pyogenic liver abscess (PLA) and amoebic liver abscess (ALA) were included. Epidemiological data, baseline characteristics, hospital course, and survival were analyzed. Overall, 11,296 admissions comprising 8,423 patients from 844 hospitals across Thailand were eligible for analysis. The mean age was 52 ± 17 years and 66.1% of patients were male. ALA was significantly prevalent in southern and western border regions of Thailand, and PLA occurred nationwide. The highest incidence of liver abscess occurred in the rainy season (June-November, P < 0.01). The median length of hospital stay was 8 days (interquartile range = 4-13 days), and mean direct cost of hospitalization was 846 ± 1,574 USD. The overall inhospital mortality rate was 2.8%. Incidence of ALA decreased over the 5-year study period, whereas PLA incidence increased (P < 0.01). Using multivariable Cox regression methods with stepwise variable selection, we developed a final model with five highly significant baseline parameters associated with increased 60-day mortality: older age, PLA, underlying chronic kidney disease, cirrhosis, and human immunodeficiency virus infection. Range of estimated probability of 60-day survival was 95-16% at cumulative risk score 0-13. This simplified score is practical, and may help clinicians prioritize patients requiring more intensive care.

Nucleos(t)ide analogues treatment outcome in genotype B and C chronic hepatitis B

Background: Hepatitis B genotypes influence the course and severity of the disease. Aim: To compare the treatment outcome of chronic hepatitis B genotype B and C patients after treating with nucleos(t)ide analogues for six months. Patients and Methods: Forty chronic hepatitis B patients attending the liver clinic of Hospital for Tropical diseases, Bangkok, were studied in retrospective cohort design. Six genotype B patients (15%) and thirty-four genotype C patients (85%) were treated. Serum hepatitis B viral load, serum alanine amino transferase level, HBeAg status and alpha-feto protein level were measured at the time of starting nucleos(t) analogues therapy, and six months later. Besides, achievement of undetectable viral load was assessed in patients with normal serum alanine amino transferase compared to patients with high serum alanine amino transferase level. Results: After six months of nucleos (t) analogues treatment, achievement of undetectable hepatitis B viral load was higher in genotype B patients (66.7%) than in genotype C patients (42.4%) (Relative Risk=1.57, 0.79-3.14). Biochemical remission, HBeAg seroconversion and tumor marker levels between the two groups were not significantly different. Moreover, achievement of undetectable hepatitis B viral load was significantly higher in normal alanine amino transferase level (75%) than in patients with high serum alanine amino transferase level (33.3%) on nucleos(t)ide analogue treatment (Relative Risk=2.25, 1.20- 4.20). Conclusion: Chronic hepatitis B treatment outcome between genotype B and C were not significantly different. Patients with normalized serum alanine amino transferase level tend to achieve undetectable viral load after nucleoside analogues treatment.

Liver function tests and clinical severity of dengue infection in adult patients

Purpose: Osteopenia and osteoporosis are well–recognized complications of celiac disease. The objectives of this study were to evaluate the prevalence of low bone mass in a community population of patients with known celiac disease and to analyze the relationship between low bone mass and clinical data of patients. Methods: We studied 37 patients with a well-established diagnosis of celiac disease. All patients had a retrospective historical review by filling out a questionnaire and survey. All patients underwent bone mineral density measurement by Accu Dexa bone scan of the middle finger of the nonprominent hand. Bone mineral density was determined by T scores calculated from the normative database of the manufacture. Results: Among celiacs, 10 patients (F 7 and M 3) (27%) had low bone density with a T score -1 measured by the accu dexa scan. Patients had a mean age of 67.7 years. Control studies show that the distribution of osteoporosis cases by age in men and women is about 22% and 25% respectively (CCJM 70 :( 245–253) March 2003). The mean duration of the disease in this group was 46.6 months and they were on a self-reported gluten diet for mean of 40.6 months. None of the patients were on chronic steroids and 7/10 (70%) were taking calcium supplements. Four patients were on treatment for osteoporois. One patient had a fracture due to osteoporosis. Conclusions: This study showed that patients with celiac disease have a high prevalence of low bone density. The main associated variables of low BMD were age and postmenopausal status (women). Our results show that nonpharmacologic measures such as gluten free diet are not sufficient. There has been no studies to show significant improvement in adult patients who have been on a gluten-free diet (Guidelines for osteoporosis in celiac disease and IBD, Gut. 46 Suppl 1:i1–8, 2000 Jan). Early diagnosis and effective treatment of celiac disease are the most relevant measures to protect patients from bone disease.

Incidence and spectrum of health problems among travellers to Myanmar

Background The number of international travellers visiting Myanmar increases each year. However, information about pre-travel preparation and incidence of health problems among these travellers is limited. Methods This cross-sectional study was conducted at three international airports in Thailand. Travellers returning from Myanmar completed questionnaires querying demographic profile, pre-travel health preparations and health problems during their stay in Myanmar. Results From March 2015 to May 2017, we collected and analysed questionnaires completed by 397 Thai and 467 non-Thai travellers (total: 50.1% men, median age 37 years). Non-Thai travellers were from Europe (59%), Northern America (21.4%), Asia (16.5%) and Australia or New Zealand (3.0%). Approximately 74% of non-Thais sought pre-travel health information; only 36% of Thais did so. Tourism was the main purpose for travel among both Thais (58.4%) and non-Thais (85.2%). Non-Thais were more likely than Thais to travel as backpackers and perform outdoor activities such as trekking, cycling or swimming. The average length of stay in Myanmar among non-Thais was significantly longer than that of Thais (26.58 days vs 7.08 days, P < 0.001). Health problems were reported by 22.9% of non-Thais; the most common was diarrhoea (21.0%) followed by upper respiratory tract symptoms (9.2%), fever (3.4%) and skin problems (3.0%). Only 12.6% of Thais reported health problems, the most common being upper respiratory tract symptoms (7.6%), followed by diarrhoea (3.1%), fever (2.8%) and skin problems (2.0%). Most health problems were mild and self-limited in both groups. Only one Thai and eight non-Thai travellers required a doctors visit during their trip to Myanmar, and two non-Thais required hospitalization. Conclusions Health problems are not very common among travellers to Myanmar. Overall, health problems were reported among 18.2% of travellers in our study. Most problems were mild, with spontaneous recovery. Only two foreign travellers required hospitalization.