Differences in risk factors for being either a hepatitis B carrier or anti-hepatitis C+ in a hepatoma-hyperendemic area in rural Taiwan

Genetic history of hepatitis C virus genotype 6 in Taiwan

Unlike hepatitis C virus (HCV) genotype (GT) 6, which is widely circulated in Southeast Asia and South China, GT 6 was not reported in Taiwan until 2006. GT 1b and 2a, also known as global HCV subtypes, have been reported as major GTs circulating in Taiwan. Because of improvement in genotyping kits and sequencing techniques for the subtyping of HCV, an increasing number of GT 6 subtypes have been reported, especially subtype 6a among intravenous drug users with human immunodeficiency virus infection after an outbreak since 2003. Thus, HCV GT 6 infection is regarded to be closely associated with injection drug use. However, recently, we found an unexpectedly high GT 6 prevalence in the general population in Tainan, southern Taiwan. Most of these GT 6 samples belonged to a putative novel subtype closely related to 6g and 6w instead of 6a. Phylogenetic analyses indicated that this putative 6g-related novel subtype and 6w could be indigenous in southern Taiwan for centuries. Southern Taiwan could be the origin of HCV subtype 6w. This finding might change the perspective of HCV epidemiology in Taiwan.

Gender differences in risk exposures for acute hepatitis C infection in Taiwan: a nationwide case-control study

BACKGROUND

In Taiwan, medical providers are required to report all acute hepatitis C (AHC) patients to National Notifiable Disease Surveillance System (NNDSS). Identifying factors associated with AHC may inform the strategies to prevent the spread of hepatitis C virus (HCV). We used the national surveillance data to assess gender difference in risk factors associated with AHC in Taiwan and propose control measures in at-risk groups.

METHODS

We conducted a nationwide case-control study using data from NNDSS and AHC case investigation questionnaires, for the period of March 6, 2014-December 31, 2016. Cases were AHC confirmed in NNDSS; controls were reported AHC with negative HCV nucleic acid test and negative serum anti-HCV antibody. We used bivariate analysis to identify characteristics and risk exposures for AHC and conducted gender stratified analyses.

RESULTS

We identified 602 AHC cases (66.9% males, median age 48 years) and 90 controls. Older age, male gender (OR: 1.85, 95% CI: 1.18-2.90), history of viral hepatitis (OR: 7.93, 95% CI:1.91-32.88), history of sexually transmitted infections (OR: 21.02, 95% CI: 2.90-152.43), and having healthcare-associated risk exposures (OR: 2.02, 95% CI: 1.25-3.25) were associated with AHC. Stratified analyses showed receiving intravenous infusion, history of hepatitis B, syphilis, and human immunodeficiency virus infection were risk factors for male AHC; receiving hemodialysis was risk factor for females.

CONCLUSIONS

Our study demonstrates risk factors for AHC in Taiwan with gender difference. Proper infection control practices in healthcare settings and interventions targeting male patients with HIV and other STIs, remain crucial to prevent individuals from AHC.

Low disease awareness as a contributing factor to the high prevalence of hepatitis C infection in Tzukuan, a hyperendemic area of southern Taiwan

Understanding the barriers and tackling the hurdles of hepatitis C virus (HCV) care cascades is key to HCV elimination. The current study aimed to investigate the rates of disease awareness, link-to-care, and treatment uptake of HCV in a hyperendemic area in Taiwan. Tzukuan residents from 2000 to 2018 were invited to participate in the questionnaire-based interviews for HCV. The rates of disease awareness, accessibility, and anti-HCV therapy were evaluated in anti-HCV-seropositive participants. Among 10,348 residents, 1789 (17.3%) were anti-HCV seropositive. Of these 1789 anti-HCV-seropositive participants, data of 594 participants from questionnaire-based interviews in 2005-2018 were analyzed for HCV care cascades. Overall, 24.9% of anti-HCV-seropositive HCV participants had disease awareness, 53.9% of aware participants had accessibility, and 79.8% of assessed participants had received HCV treatment, with a community effectiveness of 10.7%. HCV prevalence decreased over time, from 21.2% in the early cohort to 9.3% in the recent cohort. Disease awareness increased over time, from 15.6% to 41.7%, with the community effectiveness increasing from 1.3% to 28.8%. Lower education levels and normal liver biochemistry were associated with a lower rate of disease awareness. Notably, 68% of participants with abnormal liver biochemistry and 69% of those with advanced fibrosis (FIB-4 > 3.25) were unaware of their HCV disease. We demonstrated huge gaps in disease awareness, link-to-care, and treatment uptake in the HCV care cascade in an HCV-hyperendemic area, even in the initial era of direct-acting antiviral agents. There is an urgent need to overcome these hurdles to achieve HCV elimination.

Towards a safe hospital: hepatitis C in-hospital micro-elimination program (HCV-HELP study)

Question

Is hepatitis C virus (HCV) micro-elimination achievable at the hospital level with the structured strategies?

Findings

The multidirectional program included the HCV reflex test for hospital personnel, outpatient surveillance, a call-back system, and surveillance of cancer patients prior to chemotherapy. Through the plans of the study, 97.8% of the HCV-viremic patients successfully received linkage-to-treat. The results of each strategy sufficiently met the 2030 elimination goal by the World Health Organization (WHO).

Meaning

HCV micro-elimination is achievable at the hospital level based on patient safety, staff occupational safety and infection control.

Background and aims

Scarce data are available on in-hospital hepatitis C virus (HCV) micro-elimination strategies. This pilot study was prospectively conducted to assess the outcomes of HCV in-hospital micro-elimination program (HCV-HELP) in a single center in Taiwan.

Methods

The study included the HCV reflex test for plans A (hospital personnel), B (outpatient surveillance), C (a call-back system for anti-HCV+ patients), and D (surveillance of cancer patients prior to chemotherapy). The primary outcome measurement was that > 80% of eligible patients were enrolled in linkage-to-treat; the secondary outcome measurement was the surveillance efficacy.

Results

We recruited 930, 6072, 2376 and 233 participants into plans A, B, C, and D, respectively, from Oct 2020 to May 2021. The anti-HCV-seropositivity prevalences were 0.22% for plan A, 4.3% for B, and 3.9% for D. Two staff members were identified as HCV-viremic in plan A; these staff members successfully achieved a sustained virological response (SVR). We identified 39, 95 and 2 HCV-viremic patients in plans B, C, and D, respectively. Of these 138 HCV-viremic patients, 135 (97.8%) received direct-acting antiviral therapy, and 134 achieved SVR. Two 4-month phases were stratified to compare efficacies in the liver clinic. In the late phase, the adjusted number of HCV-viremic patients was 4.36/10,000 outpatient visits (90/200,689), which was 3.18-fold higher than that of the early phase (1.37/10,000 outpatient visits [30/212,658], odds ratio 3.18; 95% confidence interval 2.10–4.81, p < 0.0001).

Conclusion

HCV micro-elimination is achievable at the hospital level as per the structured HCV-HELP study.

Significant amelioration of hepatitis C virus infection in a hyperendemic area: longitudinal evidence from the COMPACT Study in Taiwan

OBJECTIVES

Hepatitis C virus (HCV) infection is the leading cause of cirrhosis and hepatocellular carcinoma worldwide. Tzukuan, located in the southwestern area of Taiwan, is an HCV hyperendemic area (>30%). This study aimed to assess the changing epidemiological characteristics of HCV infection and to evaluate the long-term outcomes after the implementation of public health strategies for two decades.

DESIGN

A population-based retrospective cohort study.

SETTING

A comprehensive care programme was implemented, namely COMPACT Study, in Tzukuan since 1997.

PARTICIPANTS

A total of 10 714 residents participated the screening.

OUTCOME MEASURES

The HCV status, demographic and clinical profiles of the participants were recorded and validated annually from 2000 through 2019.

RESULTS

The HCV infection prevalence rates were 21.1% (1076/5099) in 2000-2004, 18.8% (239/1269) in 2005-2009, 14.1% (292/2071) in 2010-2014 and 10.3% (234/2275) in 2015-2019 (p for trend test <0.0001). Among them, 1614 underwent repeated tests during the follow-up period. The annual incidence rates were 0.54% in 2005-2009, 0.4% in 2010-2014 and 0.22% in 2015-2019, respectively (p=0.01). In addition to old age, lower education level was a major risk factor for HCV infection across different periods. HCV infection prevalence rate among those illiterates reached 40.9%, followed by 28.5% in those with elementary school level, and <10% in those with high school or higher levels. The major risk factor has shifted from iatrogenic exposure in 2000-2009 to household transmission after 2010.

CONCLUSIONS

HCV infection has been decreasing and the epidemiological features are changing in the hyperendemic area by continuing education, prevention and treatment strategies.

The epidemiological profile of chronic hepatitis C with advanced hepatic fibrosis regarding virus genotype in Taiwan: A nationwide study

BACKGROUND/PURPOSE

This study aims at investigating the epidemiological profile of chronic hepatitis C (CHC) regarding hepatitis C virus (HCV) genotype in Taiwan.

METHODS

A total of 29,087 CHC patients with advanced fibrosis who received direct-acting antivirals (DAAs) therapy under Taiwan's National Health Insurance (NHI) during 2017-2018 were recruited. The HCV genotype distribution and its association with patients' demographic factors including age, gender, and geographical areas were examined.

RESULTS

The most common genotypes were 1b (59.5%) and 2 (30.1%) with characteristics of older age (mean ± standard deviation (SD): 66.5 ± 10.7 years and 67.3 ± 10.9 years) and female gender predominant (57.1% and 59.4%), which were associated with iatrogenic infection decades ago. Most of patients with genotype 1a (5.9%) and 6 (3.7%) infection were relatively younger (59.2 ± 12.0 years and 60.0 ± 13.8 years) and male gender predominant (59.1% and 61.1%), except Liujia and Liuying districts in southern Taiwan. The youngest group (53.2 ± 11.8 years) and most male gender predominant (74.3%) was genotype 3 (0.37%). These genotypes with characteristics of being younger and male gender predominant were highly related to injection drug use in recent years. The number of genotype 4 patients were extremely rare (n = 25) and efficacy of genotype-4-specific-DAA was significantly poorer than non-genotype-4-specific DAA (P value = 0.0411).

CONCLUSION

The significant differences in demographic characteristics among CHC patients with different HCV genotypes found in this study suggest HCV genotype was highly associated with transmission pattern and may be used as a reference for HCV control.

Secular Trends and Geographic Maps of Hepatitis C Virus Infection among 4 Million Blood Donors in Taiwan from 1999 to 2017

The prevalence of hepatitis C virus (HCV) infection in Taiwan was approximately 4% a decade ago, much higher than the worldwide average. This study aimed to assess the HCV burden among 4 million voluntary blood donors after 2 decades of prevention and treatment policies. We retrieved screening results for anti‐HCV and HCV RNA from the Database for Evaluating Voluntary Taiwanese Eligible Donors. First‐time blood donors who donated blood after 1999 and repeat donors who donated blood more than once between 2013 and 2017 were included to estimate HCV prevalence and incidence, respectively. The Cox proportional hazards model was used to estimate hazard ratios. Geographic variation in HCV prevalence and incidence in 364 townships was also analyzed. The prevalence study included 3,656,598 first‐time donors. The overall crude prevalence of anti‐HCV decreased from 15.5 to 4.5 per 1,000 donors between 1999 and 2017. Younger birth cohorts had a significantly lower prevalence of anti‐HCV. The majority of townships (64.3%) in Taiwan showed a significantly decreased prevalence. The incidence study included 1,393,014 repeat donors followed for 3,436,607 person‐years. Ninety‐eight donors seroconverted to HCV RNA positivity, resulting in an HCV incidence of 2.9 per 100,000 person‐years. Donors living in townships where HCV RNA prevalence was greater than 2 per 1,000 had at least 2.5‐fold greater risk of new HCV infection. Conclusion: HCV prevalence in Taiwanese first‐time blood donors decreased by 71% in the last 2 decades. However, townships with higher HCV prevalence also showed higher HCV incidence and require more active intervention.

Demographic and Urbanization Disparities of Liver Transplantation in Taiwan

Limited access to or receipt of liver transplantation (LT) may jeopardize survival of patients with end-stage liver diseases. Taiwan launched its National Health Insurance (NHI) program in 1995, which essentially removes financial barriers to health care. This study aims to investigate where there are still demographic and urbanization disparities of LT after 15 years of NHI program implementation. Data analyzed in this study were retrieved from Taiwan’s NHI inpatient claims. A total of 3020 people aged ≥18 years received LT between 2000 and 2013. We calculated crude and adjusted prevalence rate of LT according to secular year, age, sex, and urbanization. The multiple Poisson regression model was further employed to assess the independent effects of demographics and urbanization on prevalence of LT. The biennial number of people receiving LT substantially increased from 56 in 2000–2001 to 880 in 2012–2013, representing a prevalence rate of 1.63 and 18.58 per 10⁶, respectively. Such increasing secular trend was independent of sex. The prevalence was consistently higher in men than in women. The prevalence also increased with age in people <65 years, but dropped sharply in the elderly (≥65 years) people. We noted a significant disparity of LT in areas with different levels of urbanization. Compared to urban areas, satellite (prevalence rate ratio (PRR), 0.63, 95% confidence interval (CI), 0.57–0.69) and rural (PRR, 0.76, 95% CI, 0.69–0.83) areas were both associated with a significantly lower prevalence of LT. There are still significant demographic and urbanization disparities in LT after 15 years of NHI program implementation. Given the predominance of living donor liver transplantation in Taiwan, further studies should be conducted to investigate factors associated with having a potential living donor for LT.

The epidemiology of hepatitis C virus in the Maghreb region: systematic review and meta-analyses

Objective

To systematically review and synthesize available epidemiological data on hepatitis C virus (HCV) prevalence and incidence in the Maghreb region and to estimate the country-specific population-level HCV prevalence.

Methods

We conducted a systematic review of HCV antibody prevalence and incidence in the Maghreb countries as outlined by the PRISMA guidelines. Meta-analyses were conducted using DerSimonian-Laird random-effect models with inverse variance weighting to pool HCV prevalence estimates among general population groups.

Results

We identified 133 HCV prevalence measures and two HCV incidence measures. Among high risk groups, HCV prevalence ranged between 22% and 94% among people who inject drugs, 20% and 76% among dialysis patients, and 2% and 51% among hemophiliacs. Among intermediate-risk groups, considerable but widely variable HCV prevalence was found. Most common risk factors cited across studies were the duration of dialysis, number of transfusions, and having a history of surgery or dental work. The national HCV prevalence in Algeria was estimated at 0.3% (95%CI: 0.1–0.5), Libya 1.2% (95%CI: 1.1–1.3), Mauritania 1.1% (95%CI: 0–2.3), Morocco 0.8% (95%CI: 0.5–1.2), and Tunisia 0.6% (95%CI: 0.5–0.8).

Conclusions

HCV prevalence in the Maghreb region of the Middle East and North Africa is comparable to that in developed countries of about 1%. HCV exposures appear often to be linked to medical care and are suggestive of ongoing transmission in such settings. Injecting drug use appears also to be a major, though not dominant, contributor to HCV transmission. Further research is needed to draw a more thorough understanding of HCV epidemiology, especially in the countries with limited number of studies. HCV prevention policy and programming in these countries should focus on the settings of exposure.

A nationwide cohort study suggests chronic hepatitis B virus infection increases the risk of end-stage renal disease among patients in Taiwan

The association of chronic hepatitis B virus (HBV) infection with end-stage renal disease (ESRD) is unclear. To help clarify this we conducted a nationwide cohort study to measure the association by analyzing the claims data from the Taiwan National Health Insurance Research Database with ICD-9 codes used to identify diseases. We identified 17,758 adults who had chronic HBV infection and had not taken nucleos(t)ide analogs from 1999 to 2010 and randomly selected 71,032 matched controls without HBV in the same data set. The risk of ESRD was compared between these two cohorts. Cumulative incidences and hazard ratios were calculated after adjusting for competing mortality. The risk of ESRD was significantly higher in the HBV cohort (12-year cumulative incidence, 1.9%) than in the non-HBV cohort (0.49%) with a significant adjusted hazard ratio of 3.85. Multivariable stratified analysis further verified significant associations of ESRD with HBV in men of any age and women under the age of 60 years, but no significant association in women aged ⩾60 years. Thus, a large national cohort study indicates that untreated chronic HBV infection is associated with increased risk of ESRD. Hence, high-risk HBV-infected patients should have targeted monitoring for the development of ESRD.

Hepatitis B surface antigen prevalence among 12,393 rural women of childbearing age in Hainan Province, China: a cross-sectional study

Background

Hepatitis B virus (HBV) infection is highly endemic in China and it threats human health seriously. The hepatitis B surface antigen (HBsAg) prevalence among women of childbearing age plays an important role in mother to child transmission of HBV, as 30% ~50% of chronic carriers can be attributed to maternal-infantile transmission. However, there are few studies which have reported on the prevalence of HBsAg among women of childbearing age in China. This study aimed to determine the prevalence of HBsAg and its associated risk factors among rural women of childbearing age in Hainan, which is the highest hepatitis B virus endemic province in China.

Methods

A cross-sectional, population-based study, which included 12393 rural women aged 15 ~ 49 years, enrolled by a multistage stratified cluster sampling, was carried out in Hainan province, China, from November 2007 to December 2008. Blood samples were obtained from each study participant, and screened for HBsAg.

Results

The overall HBsAg prevalence of childbearing age women was 9.51%. Risk factors for HBsAg positivity among rural women were: lower education level (OR=1.206), lower family monthly income (OR=1.233), having an HBsAg-positive family member (OR=1.300), without an immunization history (OR=1.243), tattooing (OR=1.190), body piercing (OR=1.293), vaginoscopy history (OR=1.103) and history of induced abortion (OR=1.142).

Conclusions

There is a high HBsAg seroprevalence rate among rural women of childbearing age in Hainan province. Hence, it is necessary to take preventive measures to reduce the seroprevalence of HBsAg and to control its associated risk factors.

Prospective study of risk factors for hepatitis C virus acquisition by Caucasian, Hispanic, and Asian American patients

Commonly known risk factors for infection with hepatitis C virus (HCV) include blood transfusion, injection drug use, intranasal cocaine use, and body tattoos. We hypothesized that Asian Americans infected with HCV may not identify with these established risk factors present in Caucasians and Hispanics, and our aim was to conduct a survey of risk factors in HCV-infected patients in these ethnic groups. In this prospective study, 494 patients infected with HCV completed a detailed risk assessment questionnaire at a liver centre in Northern California from 2001 to 2008. Among subjects participating in this study, 55% identified themselves as Caucasian, 20% as Hispanic, and 25% as Asian. Asian Americans were older, less likely to smoke or consume alcohol, and have a family history of cancer compared with Caucasians and Hispanics. The laboratory profiles were similar, and genotype 1 was the most common infection in all groups (74-75%). The great majority of Caucasians (94%) and Hispanics (86%) identified with commonly known risk factors, which was in contrast to 67% of Asians (P < 0.0001). The most common risk factors in Asians were blood transfusions (50%) and acupuncture (50%). Furthermore, 74% of Caucasians and 66% of Hispanics identified more than one major risk factor, while only 20% of Asians reported having more than one risk factor (P < 0.0001). Survey for established risk factors for acquisition of HCV may be more appropriate for risk assessment of Caucasians and Hispanics, but not for Asian Americans. These findings may guide the development of HCV screening in our increasingly diverse population.

Prevalence and etiology of abnormal liver tests in an adult population in Jilin, China

BACKGROUND

Serum biochemical liver tests (LTs) (alanine aminotransferase, aspartate aminotransferase, and gamma glutamyltransferase) and platelet counts are often used to screen for chronic liver disease. We determined the prevalence and etiologies of abnormal LTs in an adult population in Jilin, China.

METHODS

A total of 3791 individuals between the ages of 18 and 79 years were interviewed and then underwent ultrasonography and blood tests.

RESULTS

The prevalence of abnormal LTs was 14.77% (560 out of 3791 subjects). The risk factors for abnormal LTs were non-alcoholic fatty liver disease (NAFLD) alone, which accounted for 11.61%, metabolic syndrome alone for 25%, or both for 22.14%. Abnormal LTs were more common in male than in female subjects. The development of abnormal LTs was correlated with older age males, increased daily alcohol intake, poor quality of sleep, smoking, fasting plasma glucose, body mass index, triglyceridemia, and low-density lipoprotein. Abnormal LTs in patients with metabolic syndrome and NAFLD were associated with high fasting plasma glucose, triglycerides, body mass index, low density lipoprotein, male, young age, poor sleep quality, smoking, and alcohol intake. However, abnormal LTs in patients with hepatitis B virus were associated with gender and increased age.

CONCLUSIONS

The results from the current study demonstrated that the prevalence of abnormal LTs is high in the population (14.77%). Metabolic syndrome, NAFLD, and alcohol intake appear to be potentially important causes of the observed abnormal LTs.

Health care risk factors among women and personal behaviours among men explain the high prevalence of hepatitis C virus infection in Karachi, Pakistan

To estimate the prevalence and identify factors associated with hepatitis C virus (HCV) infection among men and women in Karachi, Pakistan. We conducted a cross-sectional study of adult men and women in a peri-urban community of Karachi (Jam Kandah). Households were selected through systematic sampling from within all villages in the study area. All available adults within each household were interviewed about potential HCV risk factors. A blood specimen was collected to test for anti-HCV antibodies by enzyme immunoassay. We used generalized estimating equations while accounting for correlation of responses within villages to identify the factors associated with HCV infection. Of 1997 participants, 476 (23.8%) were anti-HCV positive. Overall, HCV infection was significantly associated with increasing age, ethnicity, and having received > or =2 blood transfusions, > or =3 hospitalizations, dental treatment and >5 injections among women. Among women, > or =2 blood transfusions [adjusted odds ratio (aOR) = 2.32], >5 injections during the past 6 months (aORs = 1.47), dental treatment (aOR = 1.31) and increasing age(aOR = 1.49), while among men, extramarital sexual intercourse (aOR = 2.77), at least once a week shave from barber (aOR = 5.04), > or =3 hospitalizations (aOR = 2.50) and increasing age (aOR = 1.28) were associated with HCV infection. A very high prevalence of HCV was found in the study population. Among women, unsafe health care practices, while among men extramarital sex, shaving from a barber and hospitalizations were associated with HCV infection. Efforts are needed to improve the safety of medical procedures to reduce the transmission of HCV in Pakistan [Corrections made in Summary after initial online publication.].

Geographic variations of predominantly hepatitis C virus associated male hepatocellular carcinoma townships in Taiwan: identification of potential high HCV endemic areas

PURPOSE

The proportion of B-HCC cases in Taiwan has progressively decreased over the last 20 years. It was not really due to an overall decrease in B-HCC but due to an increase in HCV-related HCC. The identification of potential HCV endemic areas in Taiwan has consequently become important.

METHODS

Data were collected retrospectively from eight Taiwan medical centers from 1981 to 2001, the geographical variations of male C-HCC townships in Taiwan were illustrated on maps. Goodness of fit was used to compare the anti-HCV prevalence in townships and cities, with the mean anti-HCV prevalence for Taiwan as a whole. Township-, city-, and county-specific prevalence of anti-HCV was presented as the median, ranges, and SMRs.

RESULTS

Geographic variation can be analyzed in only 263 townships and cities. The maps were designed on the basis of different SMRs. The mean anti-HCV prevalence for male HCC patients in Taiwan was 31.9% (95% confidence interval: 30.7-33.0). Twenty-five townships distributed throughout central-western and south-western Taiwan have significantly higher prevalence (P < 0.05) (12 townships SMR >/= 2; 13 townships 1.5 </= SMR < 2). Twenty-two townships have significantly lower prevalence (P < 0.05) (6 townships 0.5 </= SMR<1; 16 townships SMR < 0.5). Four different patterns of geographic variation in different counties were also noted and demonstrated.

CONCLUSION

We successfully highlighted some potential high HCV endemic townships in Taiwan.

Changing prevalence of hepatitis C virus infection among teenagers in an endemic area in Taiwan

Tzukuan Township in Taiwan has been reported to be an endemic area for hepatitis C virus (HCV) infection both in adults and adolescents. The maritime part of the township carries a higher prevalence than the non-maritime part and, as a consequence, several public education strategies have been introduced during the past decade. The current follow-up study aimed to clarify the changing prevalence of HCV infection among teenagers in the endemic maritime part of Tzukuan. In addition to viral hepatitis markers and biochemical profiles, we compared the epidemiological characteristics of 887 and 394 teenagers (aged 13-16 years) from the maritime part enrolled in 1995 and 2005, respectively. Compared with the results of surveillance in 1995, the prevalence of anti-HCV seropositivity (1.0% vs. 2.8%; P=0.045) and HCV RNA (0.5% vs. 2.3%; P=0.026) had decreased significantly by 2005. Transfusions and anti-HCV-positive families were the main risk factors amongst the 25 anti-HCV-positive teenagers in 1995, and became non-significant amongst the four anti-HCV-positive teenagers in 2005. In conclusion, the seroprevalence of HCV infection has significantly decreased after one decade of intervention among the teenage population in this endemic area.

Case-control study of risk factors associated with hepatitis C virus infection among pregnant women in hospitals of Karachi-Pakistan

OBJECTIVE

To identify risk factors for hepatitis C virus (HCV) infection among pregnant women seeking antenatal care in tertiary care hospitals of Karachi, Pakistan.

METHODS

We enrolled 119 cases and 238 controls. Cases were enzyme-linked immunosorbent assay (ELISA III) positive pregnant women for antibodies to HCV; controls were anti-HCV ELISA negative pregnant women.

RESULTS

The mean age of study subjects was 26 years (SD 5) ranging from 15 to 50 years. The mean number of pregnancies for cases was 4 (SD 3) and for controls was 3 (SD 2). Among cases an average number of injections in any month was 40%, history of hospitalization was 61% and household contact with jaundice or hepatitis was 35%. In the final multivariable logistic regression model, five or more gestations (aOR = 1.99; 95% CI = 1.08-3.33), > or =1 injection (aOR = 2.33; 95% CI = 1.38-3.91) per month, hospitalization (aOR = 1.78; 95% CI = 1.01-2.99) and household contact with jaundice/hepatitis (aOR = 3.32; 95% CI = 1.89-5.83) were independently associated with HCV.

CONCLUSION

Iatrogenic exposure (health care injections, hospitalizations and gestations) is the major risk factor for transmission of HCV among pregnant women.

Highly endemic hepatitis B infection in rural Vietnam

BACKGROUND AND AIM

Hepatitis B is a major public health problem in Vietnam; however, estimates of the prevalence of hepatitis B virus (HBV) and hepatitis delta virus (HDV), and risk factors in rural Vietnam are limited. The aim of this study was to determine HBV and HDV prevalence, and identify risk factors for HBV infection.

METHODS

A cross-sectional seroprevalence study was undertaken in two rural districts in Thai Binh province. The study population was randomly selected using multistage sampling. Demographic and behavioral risk information and serological samples were obtained from 837 participants.

RESULTS

Mean age was 42.3 years +/- 15.8 (range, 16-82 years), and 50.8% were female. Prevalence of anti-HBV core antibody (anti-HBc) and hepatitis B virus surface antigen (HBsAg) was 68.2% and 19.0%, respectively, and hepatitis B e antigen HBeAg was detected in 16.4% of the HBsAg-positive group. Prevalence of HDV was 1.3% in the HBsAg-positive group. Factors associated with HBV infection (anti-HBc or HBsAg positive) were age 60 years or older (OR, 3.82; 95% CI, 1.35-10.80; P = 0.01), residence in Vu Thu district (OR, 3.00; 95% CI, 2.16-4.17; P < 0.0001), hospital admission (OR, 2.34; 95% CI, 1.33-4.13; P = 0.003) and history of acupuncture (OR, 2.01; 95% CI, 1.29-3.13; P = 0.002). Household contact with a person with liver disease (OR, 2.13; 95% CI, 1.29-3.52; P = 0.003), reuse of syringes (OR, 1.81; 95% CI, 1.25-2.62; P = 0.002) and sharing of razors (OR, 1.69; 95% CI, 1.03-2.79; P = 0.04) were independent predictors of HBsAg positivity. Alanine aminotransferase (ALT) level was elevated (>40 IU/L) in 43% of the HBsAg-positive group; proportion elevated was higher in HBeAg-positive (65%) compared with HBeAg-negative (39%) individuals in this group (P = 0.02).

CONCLUSION

Hepatitis B virus infection is highly endemic in rural Vietnam. Poor infection control activities in health-care settings contribute to high HBV prevalence in this region. Universal HBV infant vaccination and improved infection control procedures are required for improved HBV control in Vietnam.

Prevalence and etiology of elevated serum alanine aminotransferase level in an adult population in Taiwan

BACKGROUND

The prevalence and etiologies of elevated alanine aminotransferase (ALT) have geographic variations and they are rarely reported in Taiwan. Through a population-based screening study, the prevalence and etiologies of elevated ALT in an adult population of Taiwan were assessed.

METHODS

A cross-sectional community study in a rural village of Taiwan was conducted in 3260 Chinese adults (age >or=18 years) undergoing ultrasonography (US), blood tests, and interviews with a structured questionnaire. The diagnostic criteria of non-alcoholic fatty liver disease (NAFLD) included alcohol intake <20 g/week for women or <30 g/week for men, negative hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, no known etiologies of liver disease, and US consistent with fatty liver.

RESULTS

The prevalence of elevated ALT was 11.4% (372/3260). The probable cause of this elevation was excess alcohol consumption in 0.8%, HBV in 28.5%, HCV in 13.2%, both HBV and HCV in 2.2%, NAFLD in 33.6%, and unexplained cause in 21.8%. The etiologic distribution of elevated ALT was similar in both genders, although elevation was more common in men compared to women (17.3%vs 6.1%, P < 0.05). The prevalence of elevated ALT in NAFLD was 18.1% (125/691), and the positive predictive value was 33.6% (125/372). The development of NAFLD was related to increasing age (age between 40 years and 64 years, odds ratio [OR] 1.59, 95% confidence interval [CI]: 1.25-2.01; age >or= 65 years, OR 1.46, 95%CI: 1.08-1.96), fasting plasma glucose (FPG) >or= 126 mg/dL (OR 1.54, 95%CI: 1.11-2.14), body mass index (BMI) >or= 25 kg/m(2) (OR 5.01, 95%CI: 4.13-6.26), triglyceridemia >or= 150 mg/dL (OR 1.96, 95%CI: 1.58-2.42), and hyperuricemia (OR 1.50, 95%CI: 1.22-1.84). Elevated ALT was related to male gender, BMI >or= 25 kg/m(2), and triglyceridemia >or= 150 mg/dL in subjects without known etiologies of liver disease (all P < 0.05).

CONCLUSIONS

Non-alcoholic fatty liver disease appears to be the commonest cause of elevated ALT and presumed liver injury in Taiwan. The development of NAFLD is closely associated with many metabolic disorders. Metabolic disorders are also related to elevated ALT in subjects without known etiologies of liver disease.

Glutathione status in the blood and tissues of patients with virus-originated hepatocellular carcinoma

OBJECTIVES

Glutathione status can be regarded as the redox status for many diseases. This study was performed to investigate the glutathione status in virus-originated hepatocellular carcinoma (HCC).

DESIGN AND METHODS

The blood and tissue samples were obtained from 24 patients. Blood samples were also obtained from 137 controls for comparison.

RESULTS

The GSH level and the ratios of GSH/GSSG and GSH/total glutathione of the blood samples from the patients were significantly lower than those of the controls, while the GSSG values were significantly higher. Meanwhile, levels of GSH and total glutathione, as well as the ratios of GSH/GSSH and GSH/total glutathione, were significantly decreased, whereas GSSG levels were significantly higher, in the HCC tissues than those of the adjacent cancer-free tissues.

CONCLUSIONS

Glutathione status in the HCC suggested that the antioxidant system is severely impaired, supporting a consistent role of the free radical cytotoxicity in the pathophysiology of the disease.

Screening for viral hepatitis among male non-drug-abuse prisoners

OBJECTIVE

To describe the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and the associated risk factors in a prison population.

MATERIAL AND METHODS

In this cross-sectional study, from November 2004 to February 2005, all 297 newly sentenced prisoners (mean age 37.5+/-11.7 years, age range 16-69 years), who had never used illicit drugs received routine blood check-ups and completed a face-to-face interview. Hepatitis B surface antigen (HBsAg) and anti-HCV antibodies were tested using the t-test, chi-square test, and logistic regression.

RESULTS

Among the 297 subjects, 13.1% were positive for HBsAg, 8.4% were positive for anti-HCV, and 1.7% were positive for combined HBsAg and anti-HCV. Logistic regression analysis demonstrated that tattooing (odds ratio=2.24, 95% CI=1.03-4.88) and an elevated alanine aminotransferase (ALAT) level (odds ratio=4.10, 95% CI=1.61-10.40) were independently related to HCV infection.

CONCLUSIONS

Screening of HBV and HCV infection in prison populations remains necessary. Tattooing and elevated ALAT level are identified as the related factors of HCV infection.

Descriptive epidemiology of hepatitis C virus among male heroin abusers in Taiwan

BACKGROUND

The purpose of this study was to explore the epidemiology of hepatitis C virus (HCV) infection and to determine the risk factors for HCV infection among heroin abusers in Taiwan.

METHODS

This was a cross-sectional study. From November 2004 to February 2005, 577 subjects, including 423 subjects (73.3%) using injectable heroin and 154 subjects (26.7%) using smoked heroin from one male prison located in Taiwan, were enrolled in this study. The mean age was 33.3 +/- 7.9 years (age range 19-65 years). Anti-HCV antibody was tested. A face-to-face interview focusing on sociodemographic information and risk behaviors was addressed. The t test, chi-squared test, and multivariate logistic regression were used.

RESULTS

The overall prevalence of anti-HCV antibody positivity was 74.9%, with 89.8% among injecting heroin abusers and 33.8% among smoking heroin abusers (P < 0.0001). The multivariate logistic regression analysis demonstrated that needle sharing was independently related to HCV infection (odds ratio = 5.25, 95% confidence interval = 2.48-11.12).

CONCLUSIONS

The prevalence of anti-HCV antibody positivity among male injecting drug abusers is high in Taiwan. Needle sharing is identified as a potential risk factor for HCV infection.

Global epidemiology of hepatitis C virus infection

Hepatitis C virus (HCV) is a major cause of liver disease worldwide and a potential cause of substantial morbidity and mortality in the future. The complexity and uncertainty related to the geographic distribution of HCV infection and chronic hepatitis C, determination of its associated risk factors, and evaluation of cofactors that accelerate its progression, underscore the difficulties in global prevention and control of HCV. Because there is no vaccine and no post-exposure prophylaxis for HCV, the focus of primary prevention efforts should be safer blood supply in the developing world, safe injection practices in health care and other settings, and decreasing the number of people who initiate injection drug use.

A higher than expected recovery rate from hepatitis C infection amongst adolescents: a community study in a hepatitis C-endemic township in Taiwan

This study investigated the prevalence of antibody to hepatitis C virus (anti-HCV), evaluated clinical manifestations of hepatitis C, and explored the risk factors amongst adolescents in an HCV-hyperendemic area in Taiwan. In December 1999, 713 students aged 13-16 years from Taishi township, in central Taiwan, were enrolled in a screening program for anti-HCV and alanine transaminase (ALT) status. Fourteen participants (M/F = 6/8) were positive for anti-HCV. Eight of the 14 later proved to be negative for HCV RNA, and they demonstrated relatively low sample rate/cut-off rate (S/CO) ratios (1.05-11.83) for anti-HCV tests. All HCV RNA negative cases had normal serum ALT levels. The other six (43%) seropositive students demonstrated HCV viraemia and greater S/CO ratios (25.66-77.49). Two of these six participants had elevated serum ALT levels. Compared to anti-HCV-negative subjects, anti-HCV-positive students exhibited significantly greater rates of exposure to one or more of the following: blood transfusion, tattooing, and earlobe piercing. This study group has a greater prevalence (2%) of anti-HCV than the general Taiwanese population at the same age. The study also reveals a lower rate (43%) of chronicity of HCV infection than that reported in the literature.

Ethnic and cultural determinants influence risk assessment for hepatitis C acquisition

BACKGROUND AND AIM

In the developed world hepatitis C virus (HCV) infection is predominantly associated with sharing contaminated equipment between injecting drug users (IDU). In developing countries inadequately sterilized medical equipment, transmission of infected blood and cultural practices have been implicated. Accurate risk factor assessment is essential for education targeted at risk reduction in culturally diverse populations.

METHODS

Ninety Australian-born Caucasians and 72 South-east Asian (SEA) HCV patients attending a Melbourne hospital liver clinic completed a questionnaire which assessed risk factor profile, perceived risk factors, knowledge of risk factors and methods to minimize transmission. Medical records were audited to identify doctor assessment of risk factors.

RESULTS

Risk factors in Caucasians were IDU, body piercing and tattooing (89%, 47% and 32%, respectively). Risk factors in SEA patients were injection therapy, dental therapy and surgery (89%, 70% and 38%, respectively). Most Caucasian patients (94%) correctly identified their mode of acquisition compared with 33% of SEA patients (P < 0.0001). Accurate risk factor documentation in medical records was more common in Caucasians (96 vs 32%; P < 0.0001). The majority of patients identified blood-to-blood and sexual/vertical transmission as important modes of acquisition. However, 33% of SEA patients believed transmission occurred through food, water and poor hygiene and 80% did not identify therapeutic injection or traditional medical practices as risk factors. Education provided to SEA patients did not address less well established routes of transmission.

CONCLUSIONS

Ethnicity influences perception and knowledge of risk factors. Improved assessment of risk factors in high-risk ethnic groups is needed. Education should be culturally appropriate and address the concerns of all populations with HCV.

Molecular epidemiological and clinical aspects of hepatitis D virus in a unique triple hepatitis viruses (B, C, D) endemic community in Taiwan

The molecular epidemiological and clinical aspects of hepatitis D virus (HDV) in a unique HBV, HCV, and HDV triple virus endemic community in southern Taiwan were investigated. A total of 2,909 residents aged 45 or older were screened for hepatitis B surface antigen (HBsAg), anti-HCV antibody, and anti-HDV antibody (specifically for HBsAg-positive carriers). Factors that might be associated with HDV infection, viral nucleic acid detection, and genotyping of HBV, HCV, and HDV were investigated. The prevalence of HBsAg and anti-HCV were 12.6% (366/2,909) and 41.6% (1,227/2,909), respectively. For HBsAg carriers, 15.3% (56/366) were positive for anti-HDV assay. Living in a higher endemic district of HCV infection (odds ratio [OR] = 3.2; 95% confidence interval [CI] = 1.7-6.3), male gender (OR = 1.9; 95% CI = 1.1-3.6) and co-infection with HCV (OR = 1.8; 95% CI = 1.0-3.3) were significantly independent factors associated with HDV infection. The detection rate of HDV RNA among anti-HDV-positive patients was only 12.7% (7/55). The mean HBV titer of triple infection group was significantly lower than in the HBV/HDV co-infection group (2.23 vs 3.05 in log(10), copies/ml, P = 0.046). HCV RNA detection among the triple infection group showed 47.4% (9/19) viremia rate and viral loads of 579,121 IU/ml in median (16,803-1,551,190 IU/ml). The prevalent genotype of HBV was type B (23/25); HCV was 1b (7/9) and HDV was IIa/IIb (4/4). Only the presence of HCV RNA predicted the presence of elevated ALT significantly (OR = 25.0; 95% CI = 3.39-184.6). In conclusion, the geographical aggregation of HDV infection paralleled that of HCV infection in this community. HCV suppressed the replication of HBV among triple vital infection patients. HBV and HDV lapsed into a remission or nonreplicative phase in most cases, and HCV acted as a dominant factor in triple viral-infected individuals. Only the presence of HCV RNA was associated with elevated ALT values, but not HBV or HDV.

Clinical characteristics and distribution of genotypes of TT virus infection in a hepatitis C virus-hyperendemic township of a hepatitis B virus-endemic country (Taiwan)

BACKGROUND

The prevalence of TT virus (TTV) viremia, without definite clinical significance, has been reported to be higher among chronic hepatitis C patients. The status and clinical characteristics of TT virus (TTV) infection and distribution of TTV genotypes in a hepatitis C virus (HCV) hyperendemic township (Masago community) in a hepatitis B virus (HBV) endemic country (Taiwan) were investigated.

METHODS

Sera from 100 Masago residents were tested for alanine aminotransferase (ALT) and markers of HBV, HCV and GB virus C/hepatitis G virus (GBV-C/HGV) and TTV-DNA. Sera of 250 blood donors as a control group were tested for TTV-DNA. Sera of Masago residents and blood donors with positive TTV-DNA were directly sequenced, and phylogenetic analyses were performed subsequently.

RESULTS

The prevalences of TTV viremia in different age groups among individuals from Masago were significantly higher than that among blood donors. In regard to the subtypes of TTV, 23, seven, two, eight, one, six and one isolate were related to the genotypes 1a, 1b, 2a, 2b, 3, 4 and 5, respectively, from Masago and 21, 14, one, nine and three isolates were related to the genotypes 1a, 1b, 2a, 2b, and 4, respectively, from donors. No clinical or virological factor was associated with TTV viremia or TTV genotypes.

CONCLUSIONS

TT Virus prevalence was higher among HCV hyperendemic township residents than blood donors with similar genotype distributions (genotype 1 was the most prevalent) in Taiwan. Neither TTV viremia nor a particular genotype was associated with HBV, HCV or GBV-C/HGV infection and abnormal ALT levels.

Efficacy and cost-effectiveness of influenza vaccination of the elderly in a densely populated and unvaccinated community

For economic reasons, the few influenza vaccination programs seen in developing countries are aimed at the high-risk elderly. To evaluate its efficacy and cost-effectiveness, we conducted a 2-month influenza vaccination campaign in southern Taiwan's A-Lein township for all the elderly. Significant differences in hospitalization and mortality between the vaccinated and unvaccinated groups were found. Age, sex, and risk group were significant for hospitalization and mortality, but only vaccination was significant for prevention. Savings for each person vaccinated were at least three times the cost of vaccination. We strongly recommend that all the elderly-not only high-risk elderly--receive an annual influenza vaccination.

Persistent hyperendemicity of hepatitis C virus infection in Taiwan: the important role of iatrogenic risk factors

The purpose of this study was to investigate determinants of endemic hepatitis C virus (HCV) infection within communities in Taiwan. A two-phase study, including a seroprevalence survey and a prevalent case-control study at the first phase, which has been published previously, and a follow-up seroconversion determination and an incident case-control study during the second phase, was carried out to evaluate correlates of persistent endemic HCV infection. At the first phase, a total of 12,021 men and 1,819 women who were 30-64 years old and living in seven townships in Taiwan were tested for the seroprevalence of antibodies to HCV (anti-HCV). In addition, a prevalent case-control study involving 272 HCV-positive cases and 282 seronegative controls identified from the anti-HCV testing was conducted to investigate risk factors associated with HCV prevalence. During the second phase, a total of 2,728 men and 834 women who were seronegative at recruitment participated in the 1-year prospective study on anti-HCV seroconversion. Subsequently, an incident case-control study based on 39 seroconverters and 81 persistently seronegative controls were carried out to elucidate determinants of HCV seroconvertion. Antibodies to HCV were tested by the second-generation enzyme immunoassay. Information on risk factors of HCV infection was collected from subject interviews. The prevalence of anti-HCV consistently increased with age (range 2.9-5.4%), whereas no apparent age trend was observed for anti-HCV seroconversion rate (range 0.9-1.7%). A striking geographical variation in seroprevalence and seroconversion rates of anti-HCV was observed in the study townships. Furthermore, a significant geographical correlation between HCV seroprevalence and seroconversion rates was noted (r = 0.962, P = 0.001). From the results of both prevalent and incident case-control comparisons, medical injections were found to be the main mode to sustain the persistent endemic state of HCV infection within a community (odds ratios for prevalent and incident case-control studies were 2.5 (95% CI = 1.7-3.6) and 3.1 (95% CI = 1.4-7.1), respectively. The data indicate that the basis for HCV transmission has already been existed in study areas and the iatrogenic risk factor tended to be the major determinant for sustaining persistent endemicity within a community.

The serological and molecular epidemiology of GB virus C/hepatitis G virus infection in a hepatitis C and B endemic area

OBJECTIVES

To investigate the serological and molecular characteristics of GB virus C/hepatitis G virus (GBV-C/HGV) infection in the hepatitis C virus (HCV)/hepatitis B virus (HBV)-endemic areas in Taiwan.

METHODS

Sera from 200 residents from Masago, an HCV/HBV-endemic community in Taiwan, and 400 blood donors were tested for GBV-C/HGV RNA by using nested reverse transcription-polymerase chain reaction and for antibodies to GBV-C/HGV E2-protein (anti-E2) by an enzyme-linked immunosorbent assay. Phylogenetic analysis of GBV-C/HGV was performed.

RESULTS

The prevalence of GBV-C/HGV viraemia, anti-E2 and GBV-C/HGV exposure among residents of Masago was significantly higher than that among donors (17.0%, 25.5% and 39.5% vs. 3.3%, 7.5% and 10.3%, respectively; all P < 0.0001). In Masago, the prevalence of GBV-C/HGV exposure was significantly higher in residents exposed to HCV than in those without HCV exposure (45.8% vs. 24.1%;P< 0.005). Based on multivariate analyses, HCV viraemia was the only significant factor associated with elevated levels of alanine aminotransferase in Masago. Phylogenetic analysis showed all 34 GBV-C/HGV isolates from Masago clustered within genotype 3.

CONCLUSIONS

GBV-C/HGV was highly prevalent in Masago, an HCV/HBV-endemic community in Taiwan. HCV viraemia played the most important clinical hepatopathic role in the area. Infections with other hepatitis viruses did not influence the anti-E2 seroconversion from GBV-C/HGV infections.

Transmission of hepatitis C virus in Asia: past and present perspectives

Hepatitis C virus (HCV) infection is a major public health problem. The epidemiology of HCV infection in different parts of Asia is similar, with an average seroprevalence of hepatitis C antibody (anti-HCV) less than 2.5% in healthy adults. The infection is rarely seen in children. The major routes of HCV transmission in Asia during the past few decades have been through administration of therapeutic blood products and injecting drug use, similar to the pattern observed in other parts of the world. However, obvious parenteral routes of transmission only account for 30-60% of anti-HCV-positive cases, depending on the geographic area. Other inapparent parenteral or per-mucosal exposures, including medical intervention, tattooing, acupuncture, vertical and sexual transmission, accidental needlestick and household contact, are also possible routes of HCV transmission. Although screening of blood donors for anti-HCV and improvements in infection control have significantly decreased the exposure to HCV, it is believed that HCV is still spreading in some areas of Asia because of the lack of routine screening of donated blood, injecting drug usage, traditional medicine practices or medical treatment under suboptimal hygienic conditions that involve blood contamination, and tattooing. Accordingly, until effective and safe immunoprophylaxis is available, interruption of transmission routes, such as implementation of blood donor screening for anti-HCV, adequate sterilization of surgical instruments or the use of disposable medical instruments, especially needles and syringes, and avoidance of sharing personal grooming aids remains the mainstay to prevent HCV infection in Asia today.