Evolution of the prevalence of hepatitis C virus infection and hepatitis C virus genotype distribution in human immunodeficiency virus-infected patients in Italy between 1997 and 2015

OBJECTIVES

To analyse the variation of hepatitis C virus (HCV) prevalence and genotype distribution and their determinants in people living with human immunodeficiency virus (HIV) who entered care between 1997 and 2015.

METHODS

HIV-infected patients enrolled in ICONA who were tested for HCV antibodies (HCV-Ab) were included.

RESULTS

Overall 3407 of 12 135 (28.1%) were HCV-Ab+; and 735 of 12 135 (6.1%) were HBsAg+. Among patients whose HCV genotype was known, the most represented were genotypes 1 and 3. The prevalence of HCV infection decreased from 49.2% (2565/5217) during 1997-2002 to 10.2% (556/5466) during 2009-2015. The frequency of genotype 1a increased from 29.0% (264/911) to 43.0% (129/300), whereas genotype 3 decreased from 38.5% (351/911) to 27.0% (81/300). Independent predictors of HCV-Ab+ status were being female (adjusted OR (AOR) 1.23, 95% CI 1.04-1.50, p = 0.01), risk category (versus injecting drug users: men who have sex with men AOR 0.01, 95% CI 0.01-0.01, p <0.001; heterosexuals AOR 0.01, 95% CI 0.01-0.01, p <0.001; other/unknown AOR 0.02, 95% CI 0.01-0.02, p <0.001), being cared for in Central Italy (versus being cared for in Northern Italy: AOR 0.85, 95% CI 0.73-0.98, p <0.001), being Italian-born (AOR 1.44, 95% CI 1.16-1.80, p = 0.001) and being enrolled in less recent calendar years (versus 1997-2002: 2009-2015 AOR 0.23, 95% CI 0.19-0.27, p <0.001; 2003-2008 AOR 0.49, 95% CI 0.41-0.61, p <0.001).

CONCLUSIONS

The prevalence of HCV infection in HIV-infected patients entering into care in Italy significantly declined in more recent calendar years. After adjusting for risk factors and calendar years, HCV co-infection was more frequent in females and in those born in Italy.

Global epidemiology of hepatitis C virus infection: An up-date of the distribution and circulation of hepatitis C virus genotypes

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.