[72] Chronic infection is characterized by a prolonged asymptomatic phase. The development of hepatic check details fibrosis may lead to cirrhosis, end-stage liver disease (eg, ascites, hepatic encephalopathy, and esophageal varices), and HCC. The risk of contracting HCV in travelers is thought to be low but there is a paucity of data regarding

travel-associated HCV acquisition. However, in a retrospective cohort study of 361 Australian travelers to Asia, we have provided the first estimate of the incidence of HCV infection in travelers: two travelers were found to have evidence of acute seroconversion, representing an incidence density of 1.8 infections per 10,000 travel days (95% CI: 0.22–6.53).[33] Parenteral exposure accounts for the majority of HCV infections in highly endemic countries. Travelers often undertake activities that place them at risk of acquiring HCV infection,[24, 36] including IDU or tattooing. The magnitude of the risk will depend on the prevalence of HCV in the destination country. The prevalence of HCV antibodies in a study of 515 Danish merchant

seamen who traveled was found to be 1.2% (6 of 515). In this study, five of the seamen had tattoos and one had undergone an operation abroad.[73] In contrast, in a study of 328 American missionaries with prolonged stays in tropical and subtropical countries, the incidence of HCV was low (0.6%).[28] IDU travelers appear to have higher rates of needle sharing than nontravelers.[74, 75] In a recent study within the United States, IDU travelers compared with nontravelers were more likely to be HCV positive. Travel was associated with greater sharing of GSK-3 assay needles, syringes, and drug preparation equipment as well as pooling money

to buy drugs, heavy alcohol consumption, polysubstance use, and more sexual and injecting partners.[76] A number of Linifanib (ABT-869) case reports highlight the potential for HCV acquisition in travelers when medical care is accessed overseas. Acute HCV infection has been reported in travelers who received emergency medical care in India and Pakistan,[77, 78] and a prospective surveillance study of 131 patients traveling outside the UK identified 4 cases of HCV infection in patients who received hemodialysis in either Pakistan, Slovakia, Singapore, or Bangladesh.[79] Separate studies identified patients from hemodialysis units in the UK and Canada who acquired HCV infection from hemodialysis in Asia and India.[80, 81] Currently, there is no vaccine available for HCV infection and immune globulin does not provide protection. Prospective travelers need to be advised about the modes of transmission and avoidance of activities associated with parenteral exposure to contaminated blood. Travelers who acquire HBV or HCV infections are at risk of significant morbidity and mortality and are a potential source of infection to the wider community upon return from abroad.