Injecting drug use: A vector for the introduction of new hepatitis C virus genotypes

Table 1 The burden of hepatitis C virus infection in the WHO regions and the proportion of people who inject drugs

WHO regions	Population (millions)1	Estimated HCV seroprevalence2 (%)	Estimated prevalence of viremic persons3 (%)	Proportion of PWID lowest-highest estimates4
Africa	1396	1.0-5.3	0.6-4.1	55-97
Latin America	572	0.9-1.3	0.6-1.0	69-96
North America	355	1.3	0.8-1.0
Europe	751	0.9-3.3	0.6-2.3	36-69
Asia	3985	1.1-5.4	0.7-2.3	50-53

Data sources:

¹World health statistics, 2014 (available from: http://www.who.int/world_health_statistics);

²Mohd Hanafiah K, 2013[3];

³Gower E, 2014[10] and Global Health Observatory Data Repository (http://apps.who.int/gho/data);

⁴World Drug report 2014[12]. PWID: Proportion of people who inject drugs; HCV: Hepatitis C virus.

Table 2 Hepatitis C virus infection prevalence in the general population and in people who inject drugs in the most populated European countries

Country	Population (millions)1	Injecting drug use (rate/1000 inhabitants)2	HCV prevalence in the general population3	HCV prevalence in PWID4
Germany	80.4	4.25-5.04	0.7	51
France	65.6	6.7-8.8	0.85	73
United Kingdom	63.7	3.3	0.6	47.9
Italy	59.5	10	3.0	61.0-64.8
Spain	41.0	0.2	1.5	73.3-85.9
Poland	38.5	2.9	1.5	44.3 72.4
Romania	20.0	NA	2.1-2.4	82.4
Netherlands	16.7	0.2	0.2	50-86
Greece	10.9	1.1	> 1.5	60-73
Sweden	9.5	4.9	0.5	83

Data sources:

¹World health statistics 2014 (available from: http://www.who.int/world_health_statistics; ^2,4ECMDDA, 2013[33];

³Mühlberger N, 2009[30] and Cornberg M, 2011[16]. NA: Not available. PWID: People who inject drugs; HCV: Hepatitis C virus.

Table 3 The worldwide prevalence of hepatitis C virus genotypes

Area	The most prevalent genotype	Frequency of other genotypes	First author
North America	G1 (80%)	G2 (11.1%)	Thomas et al[13], 2012
	1a- the most common	G3 (7.4%)
		G4 (1.2%)
Europe	G1 (60%)	G3 (20%);	Messina et al[43], 2015
	1b- the most common	G4 (18%)
South-East	G3 (65%)	G1 (25%)	Mao et al[44], 2014
Asia		G1 prevails in China, G6 also reported	Li et al[45], 2015
Middle East	G4 (70%)	G1, G2, G6	Ray et al[46], 2000
and North Africa			Ramia et al[47], 2012
Sub-Saharan and Central Africa	G4	G5 and G6, G1a, 1b, 2a, 2b	Papastergiou et al[48], 2015
South Africa	G 5	G1, 2, 3, 4	Gededzha et al[49], 2014
Asia Pacific and Latin America	G1a	G 1b, 2a, 2b	Messina et al[43], 2015
			Ohno et al[50], 1997
			Villar et al[51], 2015

Table 4 Hepatitis C virus genotypes prevalence in the European regions

European regions	The most prevalent genotype	Other genotypes	Comments	First author
Northern Europe	1a	1b, 2, 4	G1a frequent among PWID	Bruggmann et al[52], 2014
Western Europe	1b	3a (France)	G1b-common in older age groups	Messina et al[43], 2015
		4a (United Kingdom, The Netherlands, Germany)		Payan et al[53], 2005
Southern Europe	1b	2a, 2b, 2c, 4	G4 is becoming more frequent	Gower et al[10], 2014
				Cifuentes et al[54], 2015
Eastern Europe	1a	1b, 2, 3, 4	Non G1 genotypes reported in migrants	Cornberg et al[16], 2011
				Messina et al[43], 2015

Table 5 Hepatitis C virus genotypes prevalence among people who inject drugs in the most populated European countries¹

Country	G1	G2	G3	G4	G1 + G4
Germany	63	3.8	31	2.6	61
France	46	2.5	37	9.1	55
United Kingdom	49	5.7	42	0.8	50
Italy	45	3.3	38	13.0	58
Spain	54	2.3	27	16.0	69
Poland	35	0.0	57	8.7	44
Romania2	73	0.0	7	12.0	85
Netherlands	53	6.0	32	9.0	66
Greece2	24	2.8	61	11.0	36
Sweden	36	8.7	34	0.9	38

¹Data are adapted from Wiessing et al[34], 2014, with figures for

²Greece and Romania, corrected according to more recent estimates, after the recent human immunodeficiency virus/hepatitis C virus outbreaks in people who inject drugs.