**2. Epidemiology**

In most countries, surveys undertaken to establish the prevalence of HCV have focused on specific groups of individuals, for example, drug users, those indulging in high-risk sexual behavior, and blood donors who are not representative of the general population. Conse‐ quently, global estimates of HCV prevalence in the year 2008 are still not accurate [2].

Overall, the available data suggest that 130-170 million individuals are infected with HCV (approximately 2.2-3.0%) worldwide, with its highest prevalence occurring in Eastern Medi‐ terranean and African regions [2,3].

Previously undertaken analyses on global, regional, and country levels have mostly failed to estimate the correct HCV disease burden with studies based on age distribution and active infection. Most country-level studies have been carried out on the adult population; however, when these estimates were applied to a country's entire population, the disease burden was probably overestimated. In addition, studies focused on anti-HCV (antibody positive) testing overestimated the disease burden because they often included those subjects who have been cured, either spontaneously or after treatment [4].

Globally, genotype 1 (G1) has been found to account for 46% of all anti-HCV infections among adults, making it the most common, followed by G3 (22%), G2 (13%), G4 (13%), G6 (2%), and G5 (1%). Undefined or combination genotypes accounted for 3% of total HCV infections [4]. Genotype 1b was the most common subtype, accounting for 22% of all infections. However, significant regional, country, and local variations were found to exist. Infections in North America, Latin America, and Europe were predominately G1 (62-71%), with G1b accounting for 26%, 39%, and 50% of all cases, respectively. North Africa and the Middle East had a large G4 population (71%), which was attributable to the high prevalence of G4 in Egypt. When Egypt was excluded, genotype 4 accounted for 34% of all infections, and the genotype distribution of this region was dominated by G1 (46%). Asia was predominately G3 (39%) followed by G1 (36%), largely driven by the HCV infections in India and Pakistan. G1b accounted for 25% of all infections in this region. In Australasia, G1 dominated (53%), followed by G3 (39%). G1b was present in 16% of cases [4].
