Absence of Hepatitis B Resistance Mutants before Introduction of Oral Antiviral Therapy

Table 2

Presence of DNA polymerase mutations in chronic monoinfected hepatitis B treatment naïve.

Author, year	Country	Time frame	𝑁	Method(s)	Presence of DR mutations	Presence of LAM DR mutations
Matsuda et al. 2004 [7]	Japan	1976–2000	50	PCR	N	N
Matsuda et al. 2004 [8]	Japan	1995–2001	71	PCR	Y	Y
Kobayashi et al. 2001 [9]	Japan	1997–1999	18	PCR	Y	Y
Margeridon-Thermet et al. 2009 [10]	United States	1998–2007	17	PCR/UDPS	Y	Y
Amini-Bavil-Olyaee et al. 2008 [11]	Iran	2002–2006	147	PCR	N	N
Pollicino et al. 2009 [12]	Italy	2002–2007	100	PCR	N	N
Han et al. 2009 [13]	China	2005-2006	328	PCR	Y	Y
Nguyen et al. 2009 [14]	United States	2005–2008	472	PCR	Y	Y
Fung et al. 2008 [15]	Canada	2006–2008	209	RHA	Y	Y
Liu et al. 2010 [16]	China	2007-2008	192	PCR	N	N
Mirandola et al. 2011 [17]	Italy	2007–2009	255	RHA	Y	Y
Fung et al. 2009 [18]	Canada	2007–2009	311	RHA	Y	Y
Salpini et al. 2011 [19]	Europe	2007–2010	140	PCR	Y	N
Sayan et al. 2010 [20]	Turkey	2008-2009	88	PCR	Y	N
Osiowy et al. 2011 [21]	Canada	2008-2009	201	RHA/UDPS	Y	Y
Ng et al. 2009 [22]	Canada	2008-2009	175	RHA	Y	Y
Nguyen et al. 2009 [23]	United States	2009	70	RHA	N	N
Nguyen et al. 2011 [24]	United States	2009–2011	200	RHA	Y	N

Key: time frame: time range of blood sera collection; 𝑁: number of naïve treated subjects; method(s): method(s) used to detect genotypic resistance mutations; DR: drug resistance; LAM: lamivudine; PCR: polymerase chain reaction; UDPS: ultradeep pyrosequencing; RHA: reverse hybridization assay; Y: yes; N: no.