Seroprevalence of hepatitis C virus infection and its association with natural infection of hepatitis B virus among preschool children in Taiwan

Taiwan is a hyperendemic area of hepatitis B virus (HBV) infection where chronic hepatitis B is the most important cause of liver cirrhosis and hepatoma. Since, diagnostic kit for detecting hepatitis C virus (HCV) infection has been developed, HCV was found to be another important etiology of chronic liver disease. In order to study the seroprevalence of HCV infection among preschool children after mass hepatitis B vaccination program in Taiwan, a community-based survey was carried out in 54 kindergartens in 10 urban areas, 10 rural areas, and two aboriginal areas randomly selected through stratified sampling. Serum specimens of 2538 preschool children were screened for the HCV antibodies (anti-HCV) by a commercially available third-generation microparticle enzyme immunoassay and for HBV markers by radioimmunoassay methods. The multivariate-adjusted odd ratios (OR_m) with their 95% confidence intervals (CI) were estimated through the multiple logistic regression analysis. A total of 58 children were anti-HCV seropositive, giving a prevalence of 2.3%. The prevalence of anti-HCV was 1.0% (5 of 484) among aboriginal children, a significantly decreased seroprevalence compared with those among other ethnic groups after multivariate adjustment. Boys had a higher anti-HCV seroprevalence, but not statistically significantly different from girls (OR_m: 1.6; 95% CI: 0.9–2.8; p = 0.08). The seroprevalence of the age group of 3–4 years was lower than that of the age group of 5–6 years (OR_m: 2.2; 95% CI: 1.1–4.2; p = 0.02). After multivariate adjustment, preschool children with natural HBV infection had a higher anti-HCV seroprevalence, but not statistically significantly different from those without natural HBV-infection (OR_m: 2.6; 95% CI: 0.9–7.4; p = 0.08 for HBV-infected vs. uninfected). HCV infection varies with gender, residential area, and natural HBV infection. HCV and HBV might share common transmission routes in Taiwan.     

Measures to reduce HIV infection have not been successful to reduce the prevalence of HCV in intravenous drug users

The objective of the study was to determine whether measures taken to prevent human immunodeficiency virus (HIV) infection also lead to a reduction in the prevalence of hepatitis C virus (HCV) infection among intravenous drug users (IDU). Antibodies to HCV, HIV and hepatitis B virus (HBV) were determined in IDU who voluntarily attended AIDS prevention and information centres for the first time between 1990 and 1996. Of the 5473 IDU studied, determination of HCV was done in 3238 cases. The prevalence of antibodies to HCV was 85%. During the first period studied (1990–1992), the prevalence of antibodies to HCV was 84.5%, during the second (1993–1994) 84.1% and during the third (1995–1996) 87%; in the case of HBV the prevalence during the three periods was 74.5, 67.6 and 66.8% respectively, and for HIV it was 41.9, 38.8 and 36.6% respectively (RR: 0.72; 95% confidence interval (CI): 0.65–0.81). Among drug users addicted for less than 2 years, the trend of the prevalence of antibodies to HCV and HBV remained constant, while the prevalence of HIV infection decreased (RR: 0.61; 95% CI: 0.42–0.89). Measures to prevent transmission of HIV in drug users do not lead to a reduction in the prevalence of HCV infection. Further study is necessary to obtain a better understanding of how HCV is transmitted among drug users in order to apply measures which are effective in preventing HCV infection.     

Standardized Prevalence Ratios for Chronic Hepatitis C Virus Infection Among Adult Japanese Hemodialysis Patients

Background

Many studies have estimated the prevalence of anti-hepatitis C virus (HCV) antibody among hemodialysis (HD) patients; however, the prevalence of HCV core antigen—which indicates the presence of chronic HCV infection—is not known.

Methods

Standardized prevalence ratios (SPRs) for anti-HCV antibody and HCV core antigen among HD patients (n = 1214) were calculated on the basis of data from the general population (n = 22 472) living in the same area.

Results

The prevalences of anti-HCV antibody and HCV core antigen were 12.5% and 7.8%, respectively, in male hemodialysis patients, and 8.5% and 4.1% in female hemodialysis patients. The SPRs (95% confidence interval) for anti-HCV antibody and HCV core antigen were 8.39 (6.72–10.1) and 12.9 (9.66–16.1), respectively, in males, and 5.42 (3.67–7.17) and 8.77 (4.72–12.8) in females.

Conclusions

The prevalences of chronic HCV infection among male and female HD patients were 13-fold and 9-fold, respectively, those of the population-based controls. Further studies should therefore be conducted to determine the extent of chronic HCV infection among HD patients in other populations and to determine whether chronic HCV infection contributes to increased mortality in HD patients.Key words: hepatitis C virus infection, hemodialysis, standardized prevalence ratio (SPR), population-based study, cross-sectional analysis     

Hepatitis C virus infection in family setting

To evaluate risk factors associated with intrafamiliar transmission of hepatitis C virus (HCV), 113 hepatitis C virus index subjects with chronic HCV infection and their 267 family contacts were studied from January 1994 to October 1995. Overall, 16 family contacts (6%) were positive for anti-HCV by ELISA II generation. The prevalence was 11.3% in spouses and 2.9% in other relatives (odds ratios: 4.2; 95% CI: 1.4–12.6). Spouses who had been married to the index cases longer than 20 years had a 7.5–fold risk (95% CI: 1.0–336.3) of HCV seropositivity as compared to those married less than 20 years. In univariate analysis HCV seropositivity was associated with surgical intervention, use of glass syringes and hospitalization. The results of multivariate logistic analysis showed that any parenteral exposure (odds ratios: 3.8; 95% CI: 1.2–12.8) and sexual contact with an anti-HCV index case (odds ratios: 3.0; 95% CI: 1.0–9.4) were both independent predictors of HCV seropositivity among household contacts of HCV positive index cases. These findings indicate that sexual contact and any parenteral exposure both play an independent role in the spread of HCV infection in the family setting.     

HCV and GBV-c/HGV infection in HIV positive patients in southern Italy

Flaviviridae–hepatitis C virus (HCV) and GB virus C/hepatitis G virus (GBV-C/HGV) – and human immunodeficiency virus (HIV) frequently show similar modes of transmission. HCV and GBV-C/HGV infection was assessed in 134 consecutive patients with evidence of HIV infection, living in Campania, Italy. Data obtained from this cohort were compared with those obtained from 252 age- and sex-matched HCV infected patients without evidence of HIV infection (HCV control group). Following enzymatic immunoassays, samples were tested for the presence of HCV-RNA by RT-PCR. The HCV-RNA positive sera were genotyped by LiPA procedure. The prevalence of HCV infection in HIV patients was 19.40% and the largest group of HIV–HCV co-infected patients (84.62%) was represented by intravenous drug users (IVDU). The distribution of HCV genotypes in HIV–HCV patients was different, compared to that observed in HCV control group. HCV genotypes 1a (50%) and 3a (23.08%) were more frequently detected in HIV–HCV patients, compared to HCV control group (5.16 and 5.56% for 1a and 3a, respectively). Conversely, HCV genotypes 1b (55.70%) and 2a/2c (30.26%) were more represented in HCV control group, compared to HIV–HCV patients (15.38 and 0% for 1b and 2a/2c, respectively). GBV-C/HGV seroprevalence was 41.04% in HIV patients and 6.54% in healthy control individuals. Differently from HCV, GBV-C/HGV infection did not correlate to a preferential risk behaviour in the HIV cohort. Comparative analysis of HCV and GBV-C/HGV infection indicates that the use of injecting drugs might play a key role in the epidemiology of HCV and, in particular, of 1a and 3a HCV genotypes, in HIV patients.     

Prevalence of serologic markers of HBV, HDV, HCV and HIV in non-injection drug users compared to injection drug users in Gran Canaria, Spain

Injection drug use (IDU) is one of the most significant risk factors for viral hepatitis (B, D and C) and human immunodeficiency virus (HIV) infection. However, there is little information about the risk of infection among non-injection drug users (non-IDUs). The present study was designed to perform several objectives: (a) to evaluate the prevalence of serological markers of hepatitis B, D, C virus and HIV in IDU and non-IDU patients; (b) to compare the prevalence of these markers between both groups; (c) to identify risk factors for HCV and HIV in this population; and (d) to correlate the presence of HCV and liver function. A total of 385 consecutive patients (122 IDUs and 263 non-IDUs), admitted to the Drug Dependency Treatment Unit at the Hospital Insular of Gran Canaria between 1993 to 1994, were included in the study. The serological markers of HBV, HDV, HCV and HIV were determined by ELISA and immunoblot methods. In all cases we also measured syphilis tests (RPR and FTAabs), serum aminotransferases and serum gammaglutamiltranspeptidase. Compared to the non-IDU, the IDU group presents a higher prevalence of antiHBc (55.0% vs. 20.7%, p < 0.0001), antiHCV (87.6% vs. 35.3%, p < 0.0001) and antiHIV (21.8% vs. 2.7%, p < 0.0001). There was no significant difference in RPR positivity (0.9% vs. 4.9%, p = 0.06). Delta infection was only detected in injection drug users, and the prevalence was low. Using logistic regression, the only risk factors associated with antiHCV positivity were injection drug addiction (OR: 9.2, 95% CI: 4.9–17.0) and antiHBc positivity (OR: 5.5, 95% CI: 3.0–9.9). Similarly, the associated risk factors for HIV were injection drug addiction (OR: 5.9, 95% CI: 2.3–15.0) and antiHBc positivity (OR: 3.8, 95% CI: 1.5–9.2). However, no correlation was found between antiHCV positive and antiHIV or between these markers and RPR positivity. Patients positive for antiHCV showed significant elevations in aspartate aminotransferase and alanine aminotransferase levels, when compared with patients negative for antiHCV: 65.0 vs. 39.2 U.l (p < 0.001) and 88.4 vs. 40.3 U/l (p < 0.001), respectively. We conclude that drug users have an elevated prevalence of HCV, HBV and HIV infection, even if drug use is only inhalated. On the other hand, the main risk factors associated with HCV and HIV are injection drug addiction and exposure to hepatitis B virus. Finally, in the study population, liver dysfunction is closely related to HCV infection.     

Influence of maternal human immunodeficiency virus (HIV) co-infection on vertical transmission of hepatitis C virus (HCV): a meta-analysis

BACKGROUND: Maternal co-infection with human immunodeficiency virus (HIV) has been implicated as a potentially important co-factor for enhanced vertical transmission of hepatitis C virus (HCV). In previous reports, however, methodological issues (notably small sample sizes) have limited accurate evaluation of the contribution of maternal co-infection with HIV on the risk of vertical transmission of HCV. METHODS: A systematic review and subsequent meta-analysis of current published and unpublished reports was performed. Odds ratios (OR) and 95% CI for individual studies were calculated with maternal HIV serostatus as the exposure measure and HCV vertical transmission as the outcome measure. Overall summary estimates were then calculated using a random effects model that estimates a weighted average of OR from individual studies. RESULTS: In total, 2382 infants from 10 studies were included in an analysis of HCV-infected mothers (defined by anti-HCV+ antibody assays) with and without concomitant HIV infection. The risk estimate (OR) of HCV vertical transmission was 2.82 (95% CI: 1.78-4.45; P = 0.00001) from anti-HCV+/HIV+ co-infected mothers compared with anti-HCV+/HIV- mothers. In a subanalysis of 1327 infants born to viraemic (HCV RNA+) mothers, the risk estimate of HCV vertical transmission was 1.97 (95% CI: 1.04-3.74; P = 0.04) from HCV viraemic/HIV+ co-infected mothers compared with HCV viraemic/HIV- mothers. CONCLUSIONS: Results from this meta-analysis of observational studies suggest that the risk of HCV vertical transmission is higher in infants born to HIV co-infected mothers.     

The prevalence of hepatitis C virus antibodies among the voluntary blood donors of New Delhi,India

Infection with hepatitis C virus (HCV) is a major cause of transfusion-associated hepatitis, cirrhosis and hepatocellular carcinoma. The present study was conducted with an objective to evaluate the prevalence of anti-HCV antibody in New Delhi, India using a large number of healthy voluntary blood donors. A total of 15,898 healthy voluntary blood donors were subjected to anti-HCV testing (using a commercially available third generation anti-HCV ELISA kit) and 249 were found to be reactive for anti-HCV antibody, yielding an overall prevalence of 1.57%. No significant difference was found between the HCV positivity rate of male (1.57%; 238/15,152) vs. female (1.47%; 11/746) donors, family (1.58%; 213/13,521) vs. altruistic (1.51%; 36/2377) donors and first-time (1.55%; 180/11,605) vs. repeat (1.61%; 69/4293) donors. The age distribution of anti-HCV reactivity showed a maximum prevalence rate of 1.8% in the age group of 20–29 years. In addition, there was a clear trend of decreasing positivity for anti-HCV with increasing age and this trend was statistically significant. The results of the present study show that the prevalence of anti-HCV antibodies in the healthy voluntary blood donors of New Delhi, India is considerably higher than the reported seroprevalence of HCV in majority of the industrialized nations and this represents a large reservoir of infection capable of inflicting significant disease burden on the society. In addition, donors of New Delhi, India showed a trend of decreasing seroprevalence with increasing age, possibly implying a higher exposure rate to HCV in younger subjects.     

Assessment of the occurrence and basic determinants of hepatitis C virus (HCV) infection among medical students in Silesian voivodeship

HCV infection may result in serious health consequences such as chronic hepatitis C and liver cancer. In Poland, the data on the prevalence of HCV infection is limited and available information suggests an increased risk among young males. The aim of the study was to assess the prevalence of hepatitis C virus (HCV) infection between medical and non medical students, and to explore probable routes of HCV transmission. The project was conducted as a cross-sectional study. The study group included medical students (IV, V and VI year) and non medical students as a control group. The subjects were examined in the period from November 2002 to January 2003, (study group: n = 221; control group: n = 129). Serum samples were tested for antibody to HCV by ELISA method and anti-HCV positive samples were verified using Western Blot Line technique. Probable routes of infection were assessed by questionnaire. Preliminary results obtained in 29% of the target group suggested, that the prevalence of positive anti-HCV among students was 2.6% (95% PU: 1.2%-4.8%). It was higher among non medical than medical students (4.7% vs 1.4%). Anti-hepatitis C virus seropositivity was associated with a history of hepatitis. Verification of 9 positive anti-HCV cases proved only 1 HCV infection. Results presented in this paper are preliminary and will be verified after obtaining data for 600 medical students and for 600 subjects in the control group.     

Prevalence of hepatitis C virus infection among clients of HIV counseling and testing sites--Connecticut, 1999

Hepatitis C virus (HCV) is a common chronic bloodborne virus infection that affects an estimated 2.7 million persons in the United States. HCV infection causes an estimated 8,000-10,000 deaths each year from cirrhosis and hepatocellular carcinoma and is the leading reason for liver transplantation. Because injection drug use is a major risk factor for both human immunodeficiency virus (HIV) and HCV transmission, publicly funded HIV counseling and testing sites (HIV CTS) may have a role in HCV prevention. To evaluate the need for HCV services at these sites, the Connecticut Department of Public Health (CDPH) conducted an anonymous HCV seroprevalence study among clients of HIV CTS. This report summarizes the results of this analysis, which indicate that, among clients of these HIV CTS, the prevalence of antibody to HCV (anti-HCV) was 9.8%, compared with 1.3% for HIV, with significantly higher prevalence among clients of substance abuse treatment sites (40.2%), compared with other sites (6.9%). HCV counseling and testing should be integrated into all HIV CTS, especially those associated with substance abuse treatment.     

Risk factors for hepatitis C virus infection among blood donors in an HIV-epidemic area in Thailand.

OBJECTIVE: The role of sexual transmission in hepatitis C virus (HCV) infection has not yet been completely elucidated. This study aimed to compare the risk factors for HCV and human immunodeficiency virus (HIV) infection in an HIV epidemic area of Thailand where HIV is mainly transmitted heterosexually. DESIGN AND SUBJECTS: Sera from 3053 blood donors were collected and tested for HCV and HIV between January and March 1994. Altogether 1756 (57.5%) of the donors were interviewed about demographics and several risk factors. RESULTS: The prevalence rates of HIV and HCV infections determined by antibody assays were 2.3% and 2.2%, respectively. Sexual risk factors were clearly shown among anti-HIV positive donors. These clear associations were not found, however, among anti-HCV positive donors. In contrast, previous histories of injecting drug use and being tattooed were found in some anti-HCV positive donors but less frequently in anti-HIV positive donors. CONCLUSIONS: Sexual transmission may play a relatively minor role in HCV transmission compared with HIV, in this area.     

Risk factors for hepatitis C virus infection among Egyptian healthcare workers in a national liver diseases referral centre

Little is known about the prevalence of hepatitis C virus (HCV) among healthcare workers (HCW) in Egypt, where the highest worldwide prevalence of HCV exists. The prevalence of HCV, hepatitis B virus and Schistosoma mansoni antibodies was examined in 842 HCWs at the National Liver Institute in the Nile Delta, where >85% of patients are HCV antibody-positive. The mean age of HCWs was 31.5 years and they reported an average of 0.6±1.2 needlesticks/HCW/year. The prevalence of anti-HCV, hepatitis B surface antigen (HBsAg) and co-infection was 16.6%, 1.5% and 0.2%, respectively. HCV-RNA was present in 72.1% of anti-HCV-positive HCWs, and all but one subject were infected with HCV genotype 4. Schistosoma mansoni antibodies were present in 35.1%. The anti-HCV rate increased sharply with age and employment duration, but not among those with needlestick history. After adjusting for other risk factors, the anti-HCV rate was higher among older HCWs [P<0.001; risk ratio (RR) = 1.086, 95% CI 1.063-1.11], males (P=0.002; RR=1.911, 95% CI 1.266-2.885) and those with rural residence (P<0.001; RR=2.876, 95% CI 1.830-4.52). Occupation (P=0.133), duration of employment (P=0.272) or schistosomal antibody positivity (P=0.152) were not significant risk factors for anti-HCV positivity. In conclusion, although one in six HCWs had been infected with HCV, the infections were more likely to be community-acquired and not occupationally related.     

Prevalence of markers for hepatitis A, B and C in the German population. Results of the German National Health Interview and Examination Survey 1998

The prevalence of serological parameters indicative of infection with hepatitis A, B and C was determined using sera collected from representative population samples in the former East German (new) federal states and the West German (old) federal states during the German National Health and Examination Survey in 1998. Sera were tested for antibodies to hepatitis A virus (HAV), to hepatitis B core antigen (HBc) and to hepatitis B surface antigen (HBsAg), hepatitis C Virus (HCV), as well as for the presence of HBsAg and HCV-RNA. The mean weighted prevalence of anti-HAV was 46.5% (95% CI: 45.3–47.7) and increased markedly with age. The mean weighted prevalence of past infection with hepatitis B was 7.7% (95% CI: 7.0–8.4) in the old federal states and 4.3% (95% CI: 3.2–5.3) in the new federal states, corresponding to an overall prevalence of 7.0% (95% CI: 6.4–7.6). The mean weighted prevalence of HBsAg carriage was 0.6% (95% CI: 0.4–0.8), while the prevalence of HCV antibodies was 0.4% (95% CI: 0.2–0.5).     

Risk factors associated with hepatitis C virus infection in Taiwanese government employees

This study evaluated the roles of multiple factors in hepatitis C virus (HCV) infection, with emphasis on the modification of various individual characteristics on the risk associated with percutaneous exposure to blood. Serum samples taken from 4869 men in Taiwan within a cohort study were tested for HCV antibody. The overall positive rate of anti-HCV was 1.6%. In a logistic regression, factors positively associated with anti-HCV positivity were previous blood transfusion (odds ratio [OR] = 7.28: 95% confidence interval [CI] = 4.26-12.45), a history of surgery (OR = 2.06: 95% CI = 1 23-3.46), and lower educational levels (OR = 1.94; 95% CI = 1.14-3.32). The anti-HCV positive rate was significantly lower in hepatitis B surface antigen (HBsAg) carriers than in non-carriers (OR = 0.60; 95% CI = 0.37-0.95). Ageing, lower educational levels, O blood group, and Taiwanese ethnicity enhanced the likelihood of HCV infection through blood transfusion/surgery, whereasHBsAg status, cigarette smoking, and habitual alcohol drinking reduced it.     

Infection with human immunodeficiency virus and hepatitis viruses in Chinese drug addicts.

The prevalence of antibody against hepatitis C virus (anti-HCV) and five hepatitis B virus markers (HBVM) was measured in 176 Chinese drug addicts, of whom 23 were AIDS patients. Of 176 drug addicts, 147 were members of ethnic minorities while 29 were Han, the majority ethnic group. The total prevalence rates of anti-HCV and HBVM were 35.8% and 50.6% respectively, significantly different (P < 0.01). Anti-HCV and HBVM were together found in 22.7%. Similar prevalence rates were found among the different ethnic groups. Among the ethnic minorities, there was a significantly higher prevalence rate of anti-HCV in intravenous drug addicts (IVDA, 51.1%) than in oral drug addicts (20.3%). Furthermore, the prevalence of anti-HCV was significantly higher in needle-sharing abusers (60.4%) than in non-needle sharing ones (37.1%, P < 0.05). The prevalence of HBVM was also significantly higher in needle-sharing abusers (69.8%) than in non-needle sharing ones (34.3%). Prevalence of HBsAg was significantly higher in drug abusers with AIDS (47.8%) than in IVDA only (16.1%). The anti-HCV positive rates among ethnic minority people were: for the Yi people 69.2%, the Hui 55.6%, the Bai 53.9%, the Dai 26.8% and the Wa 23.1%. No obvious difference was identified for HBVM. The prevalence rates of HCV, HBV and HCV + HBV in IVDA showed no significant difference (P > 0.05) between the two regions. HIV, HCV and HBV infections may promote each other and be related to needle-sharing behaviour in drug abuse and to different subcultures and living habits.     

Prevalence of Hepatitis C Infection in New York City, 2004

Hepatitis C virus (HCV) is the leading cause of chronic liver disease in the United States. Accurate hepatitis C prevalence estimates are important to guide local public health programs but are usually unavailable to local health jurisdictions. National surveys may not reflect local variation, a particular challenge for urban settings with disproportionately large numbers of residents in high-risk population groups. In 2004, the New York City Department of Health and Mental Hygiene conducted the NYC Health and Nutrition Examination Survey, a population-based household survey of non-institutionalized NYC residents ages 20 and older. Study participants were interviewed and blood specimens were tested for antibody to HCV (anti-HCV); positive participants were re-contacted to ascertain awareness of infection and to provide service referrals. Of 1,786 participants with valid anti-HCV results, 35 were positive for anti-HCV, for a weighted prevalence of 2.2% (95% confidence interval [CI] 1.5% to 3.3%). Anti-HCV prevalence was high among participants with a lifetime history of injection drug use (64.5%, 95% CI 39.2% to 83.7%) or a lifetime history of incarceration as an adult (8.4%, 95% CI 4.3% to 15.7%). There was a strong correlation with age; among participants born between 1945 and 1954, the anti-HCV prevalence was 5.8% (95% CI 3.3% to 10.0%). Of anti-HCV positive participants contacted (51%), 28% (n = 5) first learned of their HCV status from this survey. Continued efforts to prevent new infections in known risk behavior groups are essential, along with expansion of HCV screening and activities to prevent disease progression in people with chronic HCV.     

Differences in Sexual Identity,Risk Practices,and Sex Partners between Bisexual Men and Other Men among a Low-Income Drug-Using Sample

Hepatitis B vaccination and targeted testing for hepatitis C virus (HCV) are recommended for jails with medical services available. This study estimates hepatitis B virus (HBV) and HCV infection prevalence among jail inmates, since most previous studies have been conducted among prison inmates. Prison and jail populations differ: jails hold a wide spectrum of persons for an average of 10–20 days, including persons awaiting arraignment, trial, conviction, or sentencing, while prisons typically hold convicted criminals for at least 1 year. A stratified random sample of sera obtained during routine syphilis testing of inmates entering jails in Chicago (March–April 2000), Detroit (March–August 1999), and San Francisco (June 1999–December 2000) was tested for serologic markers of HBV and HCV infection. All sera had been previously tested for antibody to HIV (anti-HIV). A total of 1,292 serum samples (12% of new inmates) was tested. Antibody to HCV (anti-HCV) prevalence was 13%. Antibody to hepatitis B core antigen (anti-HBc) prevalence was 19%, and hepatitis B surface antigen (HBsAg) prevalence was 0.9%; 12% had serologic evidence of hepatitis B vaccination. Hispanics had high rates of chronic HBV infection (3.6% HBsAg positive) along with Asians (4.7% HBsAg positive). Among HIV-infected persons, 38% were anti-HCV positive and 8.2% were HBsAg positive. Anti-HBc positivity was associated with anti-HCV positivity (aOR = 4.58), anti-HIV positivity (aOR = 2.94), syphilis infection (aOR = 2.10), and previous incarceration (aOR = 1.78). Anti-HCV-positivity was associated with anti-HBc positivity (aOR = 4.44), anti-HIV-positivity (aOR = 2.51), and previous incarceration (aOR = 2.90). Jail entrants had high levels of HCV and HBV infection and HIV co-infection; HBV prevalence was comparable to previous prison studies, and HCV prevalence was lower than prison studies. Hispanics had an unexpectedly high rate of chronic hepatitis B infection and had the lowest rate of hepatitis B vaccination. The finding that hepatitis B vaccination coverage among jail entrants is lower than the general population, despite this population’s increased risk for infection, highlights the need to support vaccination in jail settings.     

静脉注射吸毒人群HIV和HCV感染现状及影响因素的Meta分析

目的 了解中国内地静脉注射吸毒人群（injecting drug users,IDUs）中人类免疫缺陷病毒（human immunodeficiency virus,HIV）和丙型肝炎病毒（hepatitis C virus,HCV）感染状况及相关影响因素。方法 通过相应检索策略收集2000-2015年期间针对该人群的HIV和HCV感染状况的文献,提取数据建立数据库后进行Meta分析。结果 中国内地IDUs中HIV感染率为7.00%（95%CI:6.10%~8.00%）,HCV感染率为67.10%（95%CI:61.00%~73.20%）。亚组分析显示,不同地区、不同人群和不同时间段HIV和HCV感染率不同;单因素Meta回归分析显示HCV感染率是HIV感染率的主要影响因素,高HCV感染率组HIV感染率高于低HCV感染率组。结论 2000-2015年中国内地IDUs HIV和HCV感染率较高,HIV感染率与HCV感染率关系密切,在IDUs中可用HCV感染率的高低来评估该人群中HIV的感染和流行风险。     

Seroprevalence of hepatitis C virus and associated risk behaviours: a population-based study in San Juan, Puerto Rico

BACKGROUND: Limited information about the epidemiology of hepatitis C virus (HCV) infection is available in Puerto Rico, one of the areas hardest hit by the human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) epidemic. We estimated the prevalence of HCV infection and identified correlates of seropositivity in the municipality of San Juan, Puerto Rico. METHODS: A probability cluster design was employed to select a sample of households representative of the population aged 21-64 years in San Juan during 2001-2002. All 964 subjects completed a face-to-face interview to gather data on demographics and self-reported risk behaviours followed by venipuncture for HCV antibody testing. Variables that were at least marginally associated with HCV seroprevalence (P < 0.10) in the bivariate analyses were considered for inclusion into the multiple logistic regression model to estimate the adjusted prevalence odds ratio (POR). RESULTS: Overall weighted prevalence of HCV infection was 6.3% (95% CI 3.6-10.9%). A significant (P < 0.05) higher prevalence was observed among subjects with the following characteristics: age 30-49 (9.5%), male sex (10.6%), < or =12 years of education (9.6%), no health coverage (12.6%), lifetime heroin use (39.2%), lifetime cocaine use (39.6%), tattooing practices (34.2%), history of imprisonment (32.8%), and self-reported histories of hepatitis B virus infection (30.4%) and HIV/AIDS (92.1%). Multivariate logistic regression revealed that tattooing practices (POR = 8.9; 95% CI 1.7-44.7), lifetime cocaine use (POR = 5.5; 95% CI 2.2-13.5), blood transfusions prior to 1992 (POR = 4.0; 95% CI 1.6-10.1), lifetime heroin use (POR = 3.3; 95% CI 1.4-7.8), and history of imprisonment (POR = 2.3; 95% CI 1.1-4.9) remained significantly associated with HCV seropositivity. CONCLUSIONS: The large prevalence of HCV infection observed in Puerto Rican adults residing in San Juan suggest that HCV infection is an emerging public health concern and merits further investigation.     

Seroepidemiology of pertussis infection in an urban childhood population in Cameroon

In 1989, the prevalence of IgG antibodies to pertussis toxin (PT) in a sample of 367 unvaccinated apparently healthy children 5–14 years old was estimated by ELISA in Kumba City (Cameroon). Children were recruited using a systematic random sampling from six primary schools located in different districts of the city. The sample was representative of the various socio-economic classes.The overall prevalence was 75%; it increased from 62% in 5 year old children to 81% in children 12–14 years old (P < 0.01). IgG antibody prevalence was positively related to the family size. Children belonging to households of nine or more members had a 2.2-fold risk (C.I. 95 per cent =1.1–4.6) of previous exposure to B. pertussis infection. No association was found with the father's occupation (O.R. = 1). These findings demonstrate a great impact of pertussis infection in Cameroon, with a nearly total exposure by late childhood.Corresponding author.