Assessment of hepatitis C virus infection in two adjacent Thai provinces with drastically different seroprevalence

Abstract

Improved awareness of the hepatitis C virus (HCV) transmission has contributed to the overall decline in the HCV infection rate in some developing countries including Thailand. Chronic HCV infection in some rural Thai communities, however, presents a challenge in the efforts to treat and manage HCV-related diseases. Published and unpublished studies have suggested an unusually high incidence of HCV infection in a Thai province of Phetchabun compared to elsewhere in Thailand. To determine the magnitude of HCV infection and identify potential factors contributing to the higher rate of HCV infection in this province, we performed a population-based study in Phetchabun (n = 1667) and the neighboring Khon Kaen province (n = 1410) where HCV prevalence is much lower. Individuals between 30 and 64 years old completed detailed questionnaires designed to identify HCV risk factors and provided blood samples for anti-HCV antibody screening. The anti-HCV seropositive rates were 15.5% (259/1667) in Phetchabun and 3.6% (51/1410) in Khon Kaen. Positive samples were subsequently genotyped for HCV core gene sequence and assessed for the hepatitis B virus surface antigen (HBsAg) and human immunodeficiency virus antigen/antibody (HIV Ag/Ab). More individuals in Phetchabun possessed the combined presence of HBsAg (5.0%) and HIV Ag/Ab (0.4%) than those in Khon Kaen (3.9% HBsAg and 0.0% HIV Ag/Ab). While male gender, intravenous drug use (IVDU) and tattoos were significant HCV risk factors in both provinces (p <0.05), education less than high school and agriculture-related occupation were additionally associated with HCV in Phetchabun. HCV genotypes 6, 3, and 1 were identified in similar frequency in both provinces. We estimated that prevalence of HCV seropositivity and viremic carriers were higher in Phetchabun (143 and 111 per 1000) than in Khon Kaen (34 and 22 per 1000). Finally, we derived a simple risk factor-based scoring system as a useful preclinical tool to screen individuals at risk of chronic HCV infection prior to intervention. Knowledge gained from this study will assist in HCV screening and promote access to anti-viral treatment in high-risk groups.

HCV core antigen is an alternative marker to HCV RNA for evaluating active HCV infection: implications for improved diagnostic option in an era of affordable DAAs

“…This follow-up study examined the prevalence and genotypes of HCV found in Petchabun and Khon Kaen province and comprised part of a previous HCV surveillance project involving 3,077 samples from high- and average-level HCV-endemic areas ( Wasitthankasem et al, 2017 ). All HCV-seropositive individuals were informed of their status and invited to participate in confirmatory testing for HCV infection using anti-HCV, HCV Ag, and HCV RNA assays combined with liver enzyme levels and liver stiffness tests in March 2016.…”

“… Anti-HCV reactive samples were collected from individuals who returned to the HCV follow-up study for the treatment program (270 from the previous HCV study and 28 from self anti-HCV screening) ( Wasitthankasem et al, 2017 ). Anti-HCV nonreactive samples were excluded, and reactive samples were tested for liver function enzymes, liver stiffness, HCV RNA level and HCV Ag level.…”

Liver disease burden and required treatment expenditures for hepatitis C virus (HCV) infection in Thailand: Implications for HCV elimination in the new therapeutic era, a population-based study

“…This study was a part of an overall research project named “Prevalence and Genotypes of Hepatitis C Virus in Phetchabun and Khon Kaen Provinces as a Model for Treatment” [ 8 ]. The inclusion criteria of the overall project were: Phetchabun or Khon Kane residency, generally good health, age between 30 to 64 years, no clinical signs of immunodeficiency disease or HIV infection, and late stage of liver disease (see definition below) or hepatocellular carcinoma.…”

“…The inclusion criteria of the overall project were: Phetchabun or Khon Kane residency, generally good health, age between 30 to 64 years, no clinical signs of immunodeficiency disease or HIV infection, and late stage of liver disease (see definition below) or hepatocellular carcinoma. The study protocol set out two independent sample recruitments (one for screening and one for clinical investigation), a serological survey [ 8 ] and follow up to clinical evaluation ( Fig 1 ). Accordingly, most individuals who were positive for anti-HCV in the serosurvey were examined HCV related liver disease in this study.…”

“…They were screened for HCV serological markers. All anti-HCV antibody-positive samples were tested for HCV-RNA by reverse transcription-polymerase chain reaction (RT-PCR) [ 8 ]. In March 2016, the participants with positive serological anti-HCV results were all informed of their infection status and invited to follow-up in this clinical assessment including anti-HCV retesting, liver enzymes determination, liver stiffness evaluation, HCV RNA measurement and HCV genotyping by RT-PCR.…”