Regional Differences in Admissions and Treatment Outcomes for Hepatocellular Carcinoma Patients in Thailand.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the commonest cancers in Thailand. We report the stage and survival of patients who were admitted under the public universal health fund (NHSO) covering 47 million people to determine if there were regional disparities in the treatment outcomes in the country. METHOD: We used the 2009-2013 Nationwide Hospital Admission Data, Thailand. Patients with hepatocellular carcinoma (HCC) were identified by the ICD10 code C22.0. Procedures were identified by ICD9-CM codes, and deaths were confirmed from the NHSO database and the national citizen registry. Thailand is divided into 6 regions and Bangkok. Hospitals were identified according to their specific reimbursement codes. Survival time started from the day of first admission and was estimated using the Kaplan-Meier method. The statistical method used to compare regions was Chi-squared tests (Pearson, likelihood ratio, linear-by linear association and Mantel-cox). RESULTS: There were 36,956 HCC patients admitted during the study period. The overall median survival was 36 days. 1.63% of the patients had surgery, 0.96% had radiofrequency ablation (RFA), and 5.24% had trans-arterial chemoembolization (TACE). 90.24% did not have any tumor-specific therapy. The proportion of patients admitted for tumor-specific therapy vs. no tumor-specific therapy was significantly different between regions in all treatment modalities (p<0.01). Each treatment modality showed a wide range of median survival values across the regions (p<0.01). The best survival was seen in Bangkok, the South and the North (for surgery, RFA and TACE) and was often more than twice as long as the regions with the lowest survival, Central, East and West. CONCLUSIONS: There was a large previously-unreported disparity in admissions and outcomes in Thailand for different treatment modalities for HCC. Bangkok and the South had the best treatment outcomes and often had median survivals more than twice as long as those in the West and East. Public policy to reduce this disparity will need to be implemented in the future.

Evaluation of a genus-specific rGroEL1-524 IgM-ELISA and commercial ELISA kits during the course of leptospirosis in Thailand.

In the present study, we developed a genus-specific rGroEL1-524 IgM-ELISA assay for use in screening diagnosis of suspected leptospirosis among acute undifferentiated febrile illness patients during acute fever. The diagnostic accuracies of the rGroEL1-524 IgM-ELISA, commercial Panbio IgM-ELISA, and Virion-Serion Classic IgG-ELISA were evaluated using 133 Thai leptospirosis sera and 210 controls. Sensitivities were 91.7%, 59.6%, and 17.7% for acute infection, and the specificities were 92.6%, 90.2%, and 88.3% for the non-leptospirosis control, respectively. The rGroEL1-524 IgM-ELISA had high sensitivity, at 92.3% and 91.7%, among culture-positive and MAT-negative cases at 1-3 days post-onset of symptoms (DPO1-3), respectively. Impaired specificity on scrub typhus was found, possibly from antibody cross-reaction to ortholog GroEL. Commercial Panbio IgM-ELISA had sensitivities at DPO1-3 of 30.8% and 41.7% for culture-positive and MAT-negative cases whereas Virion-Serion IgG-ELISA showed sensitivities of 5.9% and 13.3%, respectively. The rGroEL1-524 IgM-ELISA could be useful as a screening test for early diagnosis. The performance of the commercial ELISA suggests the applicability of IgM-ELISA for diagnosis, while IgG-ELISA is useful for seroprevalence surveys. However, confirmation by reference tests is recommended.

Longitudinal Screening for Diabetic Retinopathy in a Nationwide Screening Program: Comparing Deep Learning and Human Graders.

OBJECTIVE: To evaluate diabetic retinopathy (DR) screening via deep learning (DL) and trained human graders (HG) in a longitudinal cohort, as case spectrum shifts based on treatment referral and new-onset DR. METHODS: We randomly selected patients with diabetes screened twice, two years apart within a nationwide screening program. The reference standard was established via adjudication by retina specialists. Each patient's color fundus photographs were graded, and a patient was considered as having sight-threatening DR (STDR) if the worse eye had severe nonproliferative DR, proliferative DR, or diabetic macular edema. We compared DR screening via two modalities: DL and HG. For each modality, we simulated treatment referral by excluding patients with detected STDR from the second screening using that modality. RESULTS: There were 5,738 patients (12.3% STDR) in the first screening. DL and HG captured different numbers of STDR cases, and after simulated referral and excluding ungradable cases, 4,148 and 4,263 patients remained in the second screening, respectively. The STDR prevalence at the second screening was 5.1% and 6.8% for DL- and HG-based screening, respectively. Along with the prevalence decrease, the sensitivity for both modalities decreased from the first to the second screening (DL: from 95% to 90%, p = 0.008; HG: from 74% to 57%, p < 0.001). At both the first and second screenings, the rate of false negatives for the DL was a fifth that of HG (0.5-0.6% vs. 2.9-3.2%). CONCLUSION: On 2-year longitudinal follow-up of a DR screening cohort, STDR prevalence decreased for both DL- and HG-based screening. Follow-up screenings in longitudinal DR screening can be more difficult and induce lower sensitivity for both DL and HG, though the false negative rate was substantially lower for DL. Our data may be useful for health-economics analyses of longitudinal screening settings.

Nutrition education in Southeast Sulawesi Province, Indonesia: A cluster randomized controlled study.

This study evaluated the impact of a nutrition education intervention on child feeding practices and children's nutritional status. Using a randomized controlled trial, we conducted an intervention for 6 months among caregivers with children aged 6-17 months in two subdistricts of Kendari, SE Sulawesi Province, Indonesia. In all, 22 integrated health posts were randomly assigned to an educational intervention or control group with 266 participants in both groups. Participants in the intervention group attended four nutrition classes and received a monthly home visit by cadres (community volunteers), whereas participants in the control group only received standard monthly health care at the health post. The primary study outcome was children's dietary diversity scores (DDSs). Mixed model analysis was conducted to examine the intervention effects on DDS and children's growth adjusting for clustering within subvillages. The study showed the educational intervention had a significant effect on children's DDS. Children in the intervention group had a larger DDS compared with children in the control group (Beta [mean difference] = 0.34, 95% CI: 0.02 to 0.66, P = 0.038). The intervention effect on height-for-age z-score (HAZ) could not be shown (Beta = 0.24, 95% CI: -0.06 to 0.56, P = 0.112). However, stunting prevalence remained stable in the intervention group but increased in the control group. These results indicated nutrition education delivered through nutrition classes combined with regular home visits by cadres as influencers provided a great potential to be adopted to complement other nutrition programmes in community health centres.

Thirty-Day Readmission and Cost Analysis in Patients With Cirrhosis: A Nationwide Population-Based Data.

Accurate population-based data are needed on the rate, economic impact, and the long-term outcomes of readmission among patients with cirrhosis. To examine the rates, costs, and 1-year outcomes of patients readmitted within 30 days following their index hospitalization for complications of cirrhosis, we conducted a nationwide, population-based cohort study involving all patients with cirrhosis in Thailand from 2009 through 2013, using data from the National Health Security Office databases, which included those from nationwide hospitalizations. Readmission was captured from hospitals at all health care levels across the country within the Universal Coverage Scheme. For the 134,038 patients hospitalized with cirrhosis, the overall 30-day readmission rate was 17%. Common causes of readmission consisted of complications of portal hypertension (47%) and infections (17%). After adjusting for multiple covariates, predictors of 30-day readmission included hepatocellular carcinoma (odds ratio [OR] 1.95, 95% confidence interval [CI] 1.84-2.06), human immunodeficiency virus-related admission (OR 1.81, 95% CI 1.51-2.17) and cholangiocarcinoma (OR 1.64, 95% CI 1.3-2.05). In all, 2,936 deaths (13%) occurred during readmission, and an additional 14,425 deaths up to 1 year (63.5% total mortality among readmitted patients). Causes of death were mostly from liver-related mortality. Average cost at index admission for those with a 30-day readmission were significantly higher than those readmitted beyond 30 days or not readmitted. Conclusions: Patients hospitalized with cirrhosis complications had high rates of unscheduled 30-day readmission. Average hospitalization costs were high, and only 36.5% of patients readmitted within 30 days survived at 1 year.

Evaluation of aspartate aminotransferase to platelet ratio index and fibrosis 4 scores for hepatic fibrosis assessment compared with transient elastography in chronic hepatitis C patients.

BACKGROUND AND AIM: Fibrotic stage (FS) assessment is essential in chronic hepatitis C treatment cascade. Liver stiffness measurement (LSM) using transient elastography (TE) is reliable and correlated with liver biopsy. However, TE may not be widely available. This study aimed to evaluate the diagnostic performances of aspartate aminotransferase to platelet ratio index (APRI) and fibrosis 4 (FIB-4) scores compared with TE. METHODS: We conducted a multicenter, cross-sectional study, including all chronic hepatitis C virus (HCV) monoinfection patients with successful and reliable LSM, at 10 centers in Thailand from 2012 to 2017. Characteristics and laboratory data within 3 months of TE were retrospectively reviewed. Using TE as a reference standard, the diagnostic performances of APRI and FIB-4 were evaluated. TE cut-off levels of 7.1 and 12.5 kPa represented significant fibrosis (SF) and cirrhosis, respectively. RESULTS: The distribution of FS by TE in 2000 eligible patients was as follows: no SF 28.3%, SF 31.4%, and cirrhosis 40.3%. APRI ≥ 1 provided 70.1% sensitivity and 80.6% specificity, with an area under the receiver operator characteristics curve (AUROC) of 0.834 for cirrhosis. The specificity increased to 96.3% when using a cut-off level of APRI ≥ 2. FIB-4 ≥ 1.45 provided a sensitivity, specificity, and AUROC of 52.4%, 91.0%, and 0.829 for cirrhosis, respectively. For SF, APRI performed better than FIB-4, with an AUROC of 0.84 versus 0.80 (P < 0.001). APRI score < 0.5 and FIB-4 score > 1.45 yielded sensitivities of 82.3% and 74.4% and specificities of 65.4% and 69.8%, respectively. CONCLUSIONS: APRI and FIB-4 scores had good diagnostic performances for FS assessment compared with TE, especially for cirrhosis. APRI may be used as the noninvasive assessment in resource-limited settings for HCV patients' management.

Immunodominance of LipL3293-272 peptides revealed by leptospirosis sera and therapeutic monoclonal antibodies.

BACKGROUND/PURPOSE: Leptospirosis is a neglected zoonosis, imposing significant human and veterinary public health burdens. In this study, recombinant LipL3293-147 and LipL32148-184 middle domain of LipL3293-184, and LipL32171-214, and LipL32215-272 of c-terminal LipL32171-272 truncations were defined for immunodominance of the molecule during Leptospira infections revealed by leptospirosis sera. RESULTS: IgM-dominant was directed to highly surface accessible LipL32148-184 and Lipl32171-214. IgG dominance of LipL32148-184 revealed by rabbit anti-Leptospira sera and convalescent leptospirosis paired sera were mapped to highly accessible surface of middle LipL32148-184 truncation whereas two LipL32148-184 and LipL32215-272 truncations were IgG-dominant when revealed by single leptospirosis sera. The IgM-dominant of LipL32148-214 and IgG-dominant LipL32148-184 peptides have highly conserved amino acids of 70% identity among pathogenic and intermediate Leptospira species and were mapped to the highly surface accessible area of LipL32 molecule that mediated interaction of host components. IgG dominance of two therapeutic epitopes located at LipL32243-253 and LipL32122-130 of mAbLPF1 and mAbLPF2, respectively has been shown less IgG-dominant (<30%), located outside IgG-dominant regions characterized by leptospirosis paired sera. CONCLUSION: The IgM- and IgG-dominant LipL32 could be further perspectives for immunodominant LipL32-based serodiagnosis and LipL32 epitope-based vaccine.

Association of Tumor Necrosis Factor Alpha, Interleukin 6, and C-Reactive Protein with the Risk of Developing Type 2 Diabetes: A Retrospective Cohort Study of Rural Thais.

The linkage of obesity, inflammation, and type 2 diabetes mellitus (T2DM) has been extensively investigated for over a decade. However, the association between inflammatory biomarkers, including C-reactive protein (CRP), interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-α), and T2DM is still inconsistent and limited. Thus, this study is aimed at elucidating the association between inflammatory marker levels and the risk of developing T2DM in many aspects. Among 296 subjects enrolled in 2013, 248 non-T2DM subjects who were completely reinvestigated in 2014 and 2015 were included in a 2-year retrospective analysis. Multivariate logistic regression was performed to evaluate the association of baseline inflammatory marker levels and variation with incidence of T2DM. After the 2-year follow-up, 18.6% of total subjects had developed T2DM. The risk of developing T2DM was significantly increased in subjects with a high level of baseline CRP (OR = 4.02, 95% CI: 1.77-9.12, P = 0.001), and a stronger impact was found with the combination of high CRP and IL-6 levels (OR = 5.11, 95% CI: 1.27-20.49, P = 0.021). One-year inflammatory marker variation analysis also revealed the significant association of elevated TNF-α and risk of developing T2DM (OR = 4.88, 95% CI: 1.01-23.49, P = 0.048). In conclusion, besides consideration of CRP levels alone, our findings suggested that IL-6 outstandingly plays a contributing role in T2DM progression and elevated TNF-α levels over time could be a potential predictor of T2DM.

Association between Hepatitis B Surface Antigen Levels and the Risk of Hepatocellular Carcinoma in Patients with Chronic Hepatitis B Infection: Systematic Review and Meta-Analysis.

Background: The role of hepatitis B surface antigen (HBsAg) levels in predicting the risk of developing hepatocellular carcinoma (HCC) has remained unclear. The aim of this study was to obtain the most up-to-date estimated measure of the association between HBsAg levels and the development of HCC in patients. Methods: We performed a systematic review by searching for relevant studies on PubMed, Scopus, ProQuest and the Cochrane Central Register of Controlled Trials from January 2002 to November 2017. We presented the effects of HBsAg levels at each cut-off value as the odds ratios (ORs) at 95% confidence interval (CI). We also investigated HCC and its potential risk factors including HBeAg, and HBV DNA. We registered our protocol with the International Prospective Register of Systematic Reviews (PROSPERO) with the registration number CRD42018081138. Results: We selected 10 studies representing 12 541 cases. At the 100 IU/ml cut-off, the OR for HCC at the high HBsAg level versus the low level was 4.99 (95% CI, 3.01­8.29) with high inconsistency (I2=79%). At the 1,000 IU/ml threshold, the pooled OR for HCC at the high HBsAg versus the low level was 2.46 (95% CI, 2.15­2.83) with low variance. We also found correlations between the risk of HCC and male gender (OR=2.12), hepatitis B e-antigen positivity (OR=2.99), or hepatitis B (HBV) viral load ≥ 2,000 IU/ml (OR=4.37). Conclusion: Our study revealed that HBsAg levels ≥ 100 IU/ml, and notably >1,000 IU/ ml, are associated with an increased risk of HCC development.

A Population Dynamic Model to Assess the Diabetes Screening and Reporting Programs and Project the Burden of Undiagnosed Diabetes in Thailand.

Diabetes mellitus (DM) is rising worldwide, exacerbated by aging populations. We estimated and predicted the diabetes burden and mortality due to undiagnosed diabetes together with screening program efficacy and reporting completeness in Thailand, in the context of demographic changes. An age and sex structured dynamic model including demographic and diagnostic processes was constructed. The model was validated using a Bayesian Markov Chain Monte Carlo (MCMC) approach. The prevalence of DM was predicted to increase from 6.5% (95% credible interval: 6.3-6.7%) in 2015 to 10.69% (10.4-11.0%) in 2035, with the largest increase (72%) among 60 years or older. Out of the total DM cases in 2015, the percentage of undiagnosed DM cases was 18.2% (17.4-18.9%), with males higher than females (p-value < 0.01). The highest group with undiagnosed DM was those aged less than 39 years old, 74.2% (73.7-74.7%). The mortality of undiagnosed DM was ten-fold greater than the mortality of those with diagnosed DM. The estimated coverage of diabetes positive screening programs was ten-fold greater for elderly compared to young. The positive screening rate among females was estimated to be significantly higher than those in males. Of the diagnoses, 87.4% (87.0-87.8%) were reported. Targeting screening programs and good reporting systems will be essential to reduce the burden of disease.

The incidence, etiologies, outcomes, and predictors of mortality of acute liver failure in Thailand: a population-base study.

BACKGROUND: Acute liver failure (ALF) is uncommon but progresses rapidly with high mortality. We investigated the incidence, etiologies, outcomes, and predictive factors for 30-day mortality in patients with ALF. METHODS: We conducted a population-based study of ALF patients hospitalized between 2009 and 2013 from the Thai Nationwide Hospital Admission database, which comprises 76% of all admissions from 858 hospitals across 77 provinces in Thailand. ALF was diagnosed using ICD-10 codes K72.0 and K71.11. Patients with liver cirrhosis were excluded. RESULTS: There were 20,589 patients diagnosed with ALF during the study period with 12,277 (59.6%) males and mean age of 46.6 ± 20.7 years. The incidence of ALF was 62.9 per million population per year. The most frequent causes of ALF were indeterminate (69.4%), non-acetaminophen drug-induced (26.1%), and viral hepatitis (2.5%). Acetaminophen was the presumptive cause in 1.7% of patients. There were 5502 patients (26.7%) who died within 30 days after admission. One patient (0.005%) underwent liver transplantation. The average hospital stay was 8.7 ± 13.9 days, and the total cost of management was 1075.2 ± 2718.9 USD per admission. The most prevalent complications were acute renal failure (ARF)(24.2%), septicemia (18.2%), and pneumonia (12.3%). The most influential predictive factors for 30-day mortality were ARF (HR = 3.64, 95% CI: 3.43-3.87, p < 0.001), malignant infiltration of the liver (HR = 3.37, 95% CI: 2.94-3.85, p < 0.001), and septicemia (HR = 1.96, 95%CI: 1.84-2.08, p < 0.001). CONCLUSIONS: ALF patients have poor outcomes with 30-day mortality of 26.7% and high economic burden. Indeterminate etiology is the most frequent cause. ARF, malignant infiltration of the liver, and septicemia are main predictors of 30-day mortality.

Characteristics and outcomes of cholangiocarcinoma by region in Thailand: A nationwide study.

AIM: To identify the potential risk factors of cholangiocarcinoma, we determined the characteristics of cholangiocarcinoma patients among 5 different regions of Thailand. METHODS: All patients diagnosed with cholangiocarcinoma between 2008 and 2013 were identified using the Nationwide Hospital Admission Data registry (n = 39421). Baseline characteristics, comorbidities and survival were abstracted. RESULTS: The annual incidence during the study period was stable in all regions. Most patients lived in the Northeast (62.8%), followed by the North (16.9%), Central (12.3%), Bangkok (5.4%), and South (n = 2.6%) regions (P < 0.0001). Significantly more cholangiocarcinoma patients had diabetes, cirrhosis, and chronic viral hepatitis B/C infection than non-cholangiocarcinoma participants (diabetes: 11.42% vs 5.28%; cirrhosis: 4.81% vs 0.92%; hepatitis B: 0.74% vs 0.12%; and hepatitis C: 0.50% vs 0.10%, P < 0.0001 for all, respectively). The overall 1-year mortality rate was 81.7%, with a stable trend over time. CONCLUSION: Diabetes and chronic liver diseases may be associated with cholangiocarcinoma in the Thai population.

Elevated C-reactive protein, interleukin 6, tumor necrosis factor alpha and glycemic load associated with type 2 diabetes mellitus in rural Thais: a cross-sectional study.

BACKGROUND: The elevated levels of inflammatory markers, including C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL6) are supposed to be associated with type 2 diabetes mellitus (T2DM). Frequent high glycemic load (GL) consumption, central obesity, and a lack of physical activity are considered to be T2DM risk factors. This study aimed to determine the difference of these inflammatory markers as well as GL in individuals with versus those without T2DM in rural Thais. METHODS: A total of 296 participants aged 35-66 living in Sung Noen District, Nakhon Ratchasima Province, Thailand, were recruited. Blood was collected to evaluate blood glucose levels, lipid profiles, and inflammatory markers. A Semi-food frequency questionnaire was utilized to assess GL followed by socioeconomic and anthropometric assessment. Statistical analysis was subsequently performed. RESULTS: Elevated CRP and IL6 levels were associated with increased risk of developing T2DM [OR (95% CI): 7.51 (2.11, 26.74) and 4.95 (1.28, 19.11)], respectively. There was a trend towards increased risk of T2DM with elevated TNF-α levels [OR (95% CI): 1.56 (0.39, 6.14)]. GL correlated significantly with fasting blood glucose (r = 0.289, P = 0.016), suggesting that it is involved in T2DM in this study group. CONCLUSION: In this study, CRP, IL6, and TNF-α associated with T2DM. Our findings suggested that these inflammatory markers, especially CRP, may initiate T2DM.

A significant cancer burden and high mortality of intrahepatic cholangiocarcinoma in Thailand: a nationwide database study.

BACKGROUND: We aimed to examine the burden of intrahepatic cholangiocarcinoma (ICC) in Thailand and identify the prognostic factors for all-causes of death. METHODS: We conducted a population-based study of ICC patients admitted during 2009-2013 using the Nationwide Hospital Admission Database, the National Health Security Office (NHSO). There was an average of 1,051,146 patients/year with diagnosis of gastrointestinal diseases (GI). All patients with a diagnosis of ICC (ICD10- C221) were included from a total of 72,479 admissions from 858 hospitals. The surgical resection procedures such as the radical pancreaticoduodenectomy, subtotal and partial hepatectomy were analyzed. Data for all patients were censored 1 year post-study or death, whichever came first. RESULTS: A total of 34,325 patients with ICC during a 5-year study period (on average, 6865 patients/year, with the incidence rate of 14.6 per 100,000 population, per year. The ICC patients had a mean age of 63.8+/-11.6 years and 63% were males. The mean length of hospital stay was 6.4+/-7.3 days with a mean+/-SD cost of hospitalization of $595+/-$1160 USD per admission. There were 659 patients (1.9%) underwent surgical resection. The overall survival of ICC patients with surgery was significantly better than those patients without surgery. Hazard ratio of death for patients without surgery was 2.5 (95% CI of 2.3-2.7). Approximately 14% of the ICC patients died during hospitalization. The median overall survival of all patients after the first admission was 53 +/-0.6 days. From the multivariate analysis, factors related to all-causes of death were: patients' age >60 years (OR = 1.2, 95% CI; 1.1-1.3), length of hospital stay of >7 days (OR = 1.1, 95% CI; 1.02-1.2), male (OR = 1.3, 95% CI; 1.2-1.4), living in the northern part of Thailand (OR = 1.5, 95% CI; 1.3-1.8) and presence of complications during admission (OR = 1.3, 95% CI; 1.1-1.5). CONCLUSION: The disease burden of patients with ICC in Thailand is significant with the incidence rate of 14.6 per 100,000 population, per year during 2009-2013 and showed high mortality rate of 14%.

Estimating the Impact of Expanding Treatment Coverage and Allocation Strategies for Chronic Hepatitis C in a Direct Antiviral Agent Era.

Hepatitis C virus (HCV) infection is an important worldwide public health problem, and most of the global HCV burden is in low- to middle-income countries. This study aimed to estimate the future burden of chronic hepatitis C (CHC) and the impact of public health policies using novel antiviral agents in Thailand. A mathematical model of CHC transmission dynamics was constructed to examine the disease burden over the next 20 years using different treatment strategies. We compared and evaluated the current treatment (PEGylated interferon and ribavirin) with new treatments using novel direct-acting antiviral agents among various treatment policies. Thailand's CHC prevalence was estimated to decrease 1.09%-0.19% in 2015-2035. Expanding treatment coverage (i.e., a five-fold increment in treatment accessibility) was estimated to decrease cumulative deaths (33,007 deaths avoided, 25.5% reduction) from CHC-related decompensated cirrhosis and hepatocellular carcinoma (HCC). The yearly incidence of HCC-associated HCV was estimated to decrease from 2,305 to 1,877 cases yearly with expanding treatment coverage. A generalized treatment scenario (i.e., an equal proportional distribution of available treatment to individuals at all disease stages according to the number of cases at each stage) was predicted to further reduce death from HCC (9,170 deaths avoided, 11.3% reduction) and the annual incidence of HCC (i.e., a further decrease from 1,877 to 1,168 cases yearly, 37.7% reduction), but cumulative deaths were predicted to increase (by 3,626 deaths, 3.7% increase). Based on the extensive coverage scenario and the generalized treatment scenario, we estimated near-zero death from decompensated cirrhosis in 2031. In conclusion, CHC-related morbidity and mortality in Thailand are estimated to decrease dramatically over the next 20 years. Treatment coverage and allocation strategies are important factors that affect the future burden of CHC in resource-limited countries like Thailand.

Hepatitis B vaccination for international travelers to Asia.

There is a wide range in prevalence of hepatitis B virus (HBV) infection and HBV immunization programs between different regions. Hepatitis B is a vaccine preventable disease yet is still endemic in the majority of countries in Asia. Despite the decreasing global prevalence of chronic HBV infection, there is still considerable risk of HBV infection among international travelers to high endemic areas. Numbers of international travelers are expected to increase year by year; thus immunization among this cohort is a crucial preventive measure. Among international travelers to Asia, HBV immunization should be recommended for those without previous HBV vaccination who plan to travel to countries with intermediate to high prevalence of HBV, and especially for those individuals at greater risk of HBV infection; including travelers engaging in casual sex, getting a tattoo or piercing, and those having dental surgery or other medical procedures. Longer duration of travel is also associated with a greater risk of HBV infection. Travelers from low HBV prevalence countries, especially those born before implementation of universal HBV vaccination, might benefit from HBV vaccination during long-term traveling to HBV intermediate to high endemic country.