Hepatitis C Virus in Vietnam: High Prevalence of Infection in Dialysis and Multi-Transfused Patients Involving Diverse and Novel Virus Variants

Abstract

Hepatitis C virus (HCV) is a genetically diverse pathogen infecting approximately 2–3% of the world's population. Herein, we describe results of a large, multicentre serological and molecular epidemiological study cataloguing the prevalence and genetic diversity of HCV in five regions of Vietnam; Ha Noi, Hai Phong, Da Nang, Khanh Hoa and Can Tho. Individuals (n = 8654) with varying risk factors for infection were analysed for the presence of HCV Ab/Ag and, in a subset of positive specimens, for HCV RNA levels (n = 475) and genotype (n = 282). In lower risk individuals, including voluntary blood donors, military recruits and pregnant women, the prevalence of infection was 0.5% (n = 26/5250). Prevalence rates were significantly higher (p<0.001) in intravenous drug users (IDUs; 55.6%, n = 556/1000), dialysis patients (26.6%, n = 153/575) commercial sex workers (CSWs; 8.7%, n = 87/1000), and recipients of multiple blood transfusions (6.0%, n = 32/529). The prevalence of HCV in dialysis patients varied but remained high in all regions (11–43%) and was associated with the receipt of blood transfusions [OR: 2.08 (1.85–2.34), p = 0.001], time from first transfusion [OR: 1.07 (1.01–1.13), p = 0.023], duration of dialysis [OR: 1.31 (1.19–1.43), p<0.001] and male gender [OR: 1.60 (1.06–2.41), p = 0.026]. Phylogenetic analysis revealed high genetic diversity, particularly amongst dialysis and multi-transfused patients, identifying subtypes 1a (33%), 1b (27%), 2a (0.4%), 3a (0.7%), 3b (1.1%), 6a (18.8%), 6e (6.0%), 6h (4.6%), 6l (6.4%) and 2 clusters of novel genotype 6 variants (2.1%). HCV genotype 1 predominated in Vietnam (60%, n = 169/282) but the proportion of infections attributable to genotype 1 varied between regions and risk groups and, in the Southern part of Vietnam, genotype 6 viruses dominated in dialysis and multi-transfused patients (73.9%). This study confirms a high prevalence of HCV infection in Vietnamese IDUs and, notably, reveals high levels of HCV infection associated with dialysis and blood transfusion.

Sexual transmission of Hepatitis C Virus infection in a heterosexual population: A systematic review

“…Dunford et al 31 found that 8.7% of commercial sex workers were HCV positive, and of those 40.2% (n=87) were non-PWIDs, but did not report data on the comparison group (non-PWID CSWs negative for HCV). Neaigus et al 27 found a positive effect but it was not statistically significant (unadjusted OR 2.0 (0.6-6.7); p=0.3; n=277).…”

“…Evidence of being a commercial sex worker as a risk factor for HCV infection was limited (measured in 2 studies only 27,31 ) and of very low quality (GRADE). Dunford et al 31 found that 8.7% of commercial sex workers were HCV positive, and of those 40.2% (n=87) were non-PWIDs, but did not report data on the comparison group (non-PWID CSWs negative for HCV).…”

Management of hepatitis C virus infection in hemodialysis patients

“…Prevalence of HCV infection is markedly higher in patients on maintenance hemodialysis (MHD) [3][4][5][6][7] . Chronic HCV infection detrimentally affects the life quality, decreases life expectancy, leads to renal transplant rejection, and increases the mortality of MHD patients suffering from chronic kidney failure [1,5,6] .…”

“…Chronic HCV infection detrimentally affects the life quality, decreases life expectancy, leads to renal transplant rejection, and increases the mortality of MHD patients suffering from chronic kidney failure [1,5,6] . Moreover, HCV infection has been shown to increase the prevalence of renal insufficiency, defined by serum creatinine ≥ 1.5 mg/dL; the mechanisms may include the direct HCV-related renal injury and HCV-related cirrhosis with subsequent renal impairment [7] , and this will be harmful for patients who receive renal transplantation. The rates of HCV infection in MHD patients vary markedly among different countries and hospitals.…”

Oxidative stress: A comparison of different groups of patients with Hepatitis-C in hemodialysis units

“…The prevalence of hepatitis C (HCV) virus is a public health problem, and there is a high incidence of HCV in hemodialysis (HD) patients, which affects the quality of life, life expectancy and rejection after transplantation [1,2]. Apart from the exposure to viral agents, the patients in replacement therapy units are in a constant oxidative stress process (OS) that is due to the biocompatibility of the dialyzer membrane, an imbalance of the oxidant and antioxidant systems and the effects of the dialysate components [3,4].…”