Molecular epidemiology of hepatitis B virus in Asia

Table 1 Prevalence of hepatitis B surface antigen in the general Asian population

Country	HBsAg positivity (%)	Ref.
Southeast Asia
Brunei	4.7	Sebastian et al[30]
	6.0	Alexander et al[31]
Cambodia	7.7	OI et al[14]
	10.8	Sa-Nguanmoo et al[10]
Indonesia	3.5-9.1	Hasan[11]
	4.9	Achwan et al[12]
	2.1-10.5	Lusida et al[13]
Laos	6.9	Jutavijittum et al[24]
	8.7	Sa-Nguanmoo et al[10]
Malaysia	3.0-5.0	Merican et al[22]
	0.5-1.8	Yousuf et al[23]
Myanmar	9.7	Sa-Nguanmoo et al[10]
Philippines	10.0	Lingao et al[17]
	2.0-16.0	Lansang et al[18]
	16.7	Wong et al[19]
Singapore	3.6-4.0	James et al[28]
	2.7-4.0	Ang et al[29]
Thailand	4.0	Suwannakarn et al[15]
	13.8	Louisirirotchanakul et al[16]
Vietnam	11.4	Viet et al[20]
	7.5	Reekie et al[21]
East Asia
China	2.4	Ting-Lu et al[25]
	1.0	Liu et al[26]
	10.6	Chen et al[27]
Japan	0.8	Merican et al[22]
South Korea	3.0-4.0, 6.0	Kim et al[32]
	6.0	Hyun et al[33]

HBsAg: Hepatitis B surface antigen.

Table 2 Summary of nucleos(t)ide analogues

	Lamivudine	Adefovir	Entecavir	Telbivudine	Tenofovir	Ref.
Analogue type	Nucleoside	Nucleotide	Nucleoside	Nucleoside	Nucleotide
Introduction (yr)	1999	2002	2005	2006	2008
Product name (company)	Zefix (GSK)	Hepsera (Gilead)	Baraclude (BMS)	Sebivo (Novartis)	Viread (Gilead)
Dose	100 mg	10 mg	0.5 mg	600 mg	300 mg
	Once daily	Once daily	Once daily	Once daily	Once daily
Advantage	Low cost	Effective for HIV coinfection		Possible for pregnancy	Effective for HIV coinfection	[89]
Disadvantage	High rate of drug resistance	Renal dysfunction Fanconi anemia	Not recommend for pregnancy	Renal dysfunction	Renal dysfunction Fanconi anemia
Undetectable HBV-DNA
HBeAg positive	36%	21%	67%	60%	76%	[90]
HBeAg negative	89%	72%	90%	88%	93%
HBeAg seroconversion	22%	12%	21%	23%	21%	[91]
Drug-resistance	24%	0%	0.2%	4%	0%	[92]
Drug-resistant mutation	V173l, L180M, A181T, M204V/I	A181V/T, N236T	I169T, L180M, T184A/F/L/S, S202G/I, M204V, M250V	M204V/I	A181V/T, N236T

GSK: Glaxo Smith Kline; BMS: Bristol-Myers Squibb; ; HIV: Human immunodeficiency virus; HBV: Hepatitis B virus; HBeAg: Hepatitis B e antigen.