Systematic Reviews
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2016; 22(34): 7824-7840
Published online Sep 14, 2016. doi: 10.3748/wjg.v22.i34.7824
Global epidemiology of hepatitis C virus infection: An up-date of the distribution and circulation of hepatitis C virus genotypes
Arnolfo Petruzziello, Samantha Marigliano, Giovanna Loquercio, Anna Cozzolino, Carmela Cacciapuoti
Arnolfo Petruzziello, Samantha Marigliano, Giovanna Loquercio, Anna Cozzolino, Carmela Cacciapuoti, Laboratory of Virology and Molecular Biology "V.Tridente", IRCCS Italia, Fondazione " G. Pascale", 80131 Naples, Italy
Author contributions: Petruzziello A, Marigliano S, Loquercio G and Cozzolino A acquired the data; Petruzziello A drafted the article and contributed to conception and design; Cacciapuoti C contributed to critical revision for important intellectual content; all authors approved the final version to be published.
Conflict-of-interest statement: Authors declare no conflict of interest for this article.
Data sharing statement: Participants gave informed consent for data sharing.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Arnolfo Petruzziello, PhD, Laboratory of Virology and Molecular Biology "V. Tridente", IRCCS Italia, Fondazione " G. Pascale", Via Mariano Semmola, 80131 Naples, Italy. a.petruzziello@istitutotumori.na.it
Telephone: +39-81-5903433 Fax: +39-81-5453854
Received: April 15, 2016
Peer-review started: April 18, 2016
First decision: May 12, 2016
Revised: June 28, 2016
Accepted: August 8, 2016
Article in press: August 8, 2016
Published online: September 14, 2016
Processing time: 146 Days and 10.1 Hours
Abstract
AIM

To review Hepatitis C virus (HCV) prevalence and genotypes distribution worldwide.

METHODS

We conducted a systematic study which represents one of the most comprehensive effort to quantify global HCV epidemiology, using the best available published data between 2000 and 2015 from 138 countries (about 90% of the global population), grouped in 20 geographical areas (with the exclusion of Oceania), as defined by the Global Burden of Diseases project (GBD). Countries for which we were unable to obtain HCV genotype prevalence data were excluded from calculations of regional proportions, although their populations were included in the total population size of each region when generating regional genotype prevalence estimates.

RESULTS

Total global HCV prevalence is estimated at 2.5% (177.5 million of HCV infected adults), ranging from 2.9% in Africa and 1.3% in Americas, with a global viraemic rate of 67% (118.9 million of HCV RNA positive cases), varying from 64.4% in Asia to 74.8% in Australasia. HCV genotype 1 is the most prevalent worldwide (49.1%), followed by genotype 3 (17.9%), 4 (16.8%) and 2 (11.0%). Genotypes 5 and 6 are responsible for the remaining < 5%. While genotypes 1 and 3 are common worldwide, the largest proportion of genotypes 4 and 5 is in lower-income countries. Although HCV genotypes 1 and 3 infections are the most prevalent globally (67.0% if considered together), other genotypes are found more commonly in lower-income countries where still account for a significant proportion of HCV cases.

CONCLUSION

A more precise knowledge of HCV genotype distribution will be helpful to best inform national healthcare models to improve access to new treatments.

Keywords: Hepatitis C virus genotype; Epidemiology; Hepatitis C virus; Hepatitis C virus prevalence; Hepatitis C virus infections; Viraemia

Core tip: Hepatitis C virus (HCV) infection is a global public health burden, causing an increasing level of liver-related morbidity and mortality due to the disease progression. Unfortunately, in many countries, there is a lack of robust epidemiological data, especially HCV genotypes distribution, upon which to base country-specific prevention, diagnosis and treatment strategies in order to reduce the disease burden represented by HCV. Stratification by viral genotypes at national and regional level, and a better understanding of viral diversity within target populations, might also critically inform the rational design and testing of future HCV vaccines.