Table 3.

Prevalence of chronic hepatitis B virus (HBV) infection among persons born before and after hepatitis B vaccine (HepB) introduction, and number of lives saved and total chronic HBV infections averted starting from year of vaccine introduction up to 2015 in each country—World Health Organization South-East Asia Region, 1992–2015

Country	Pre-vaccination					Post-vaccination				Recommendations
	Year of study	Sample size	Sampling	Age group (years)	% HBsAg positive	Age group (years)	% HBsAg positive in 2015	No of lives saved	Total no of chronic HBV infections averted
						Post-vaccination representative serosurvey conducted
Bangladesh	2011/12	2100 pre- and 2100 post-HepB	HH survey in 105 randomly selected mouzas	10	1.3a	5–6	0.05a (1.5b)	147,402	815,878	Validate seroprevalence to assess whether there is need for HepB-BD
Nepal	2012	1186 pre-and 2144 post-HepB	Stratified cluster HH survey	10–12	0.28 [15]	5–6	0.13[15] (0.6b)	43,296	270,168	Consider partial HepB-BD introduction in certain areas if supported by serosurvey data
Thailand	2014	2805 pre- and 3159 post-HepB	HH survey in four regions	>22–24	4.5 [13]	5–10	0.3 [13] (0.05b)	84,727	493,742	Maintain good coverage
						Nationally representative post-vaccination survey not conducted; prevalence estimated by modeling
Bhutan	1995/96	251	Hospital based survey	1–12	5.2 [23]	5–6	0.4b	1949	11,941	Evaluate vaccine impact (serosurvey)
DPR Korea	ND					5–6	0.8b	86,947	510,506	Evaluate vaccine impact (serosurvey)
India	2015	944	Community-based study in a village in rural Maharashtra state	11–30	1.2 [24]	5–6	1.0b	931,491	5,905,423	Improve coverage, conduct national serosurvey among children after higher coverage achieved
	2001/02	1838	Community-based survey in West Bengal	<10–19	2.6 [25]
	1998	1856	Community-based representative study in Tamil Nadu	15–45	5.7 [26]
Indonesia	2012	195	Convenience sample from universities in Banjarmasin	18–41	4.6 [27]	5–6	1.8b	1,054,394	6,731,634	Improve coverage, evaluate vaccine impact nationwide (serosurvey)
	2010	376	Convenience sample of high school and college students in Ternate	17–25	15.7 [28]
	2005	327	Convenience sample in Tahuna Archipelo	11–30	12.2 [29]
Maldives	ND					5–6	0.2b	1300	7050	Document vaccine impact (serosurvey)
Myanmar	2015	5547	Cross-sectional general population survey in 18 townshipsa	15–80	6.5a	5–6	3.8b	135,975	819,170	Improve HepB3 coverage, consider nationwide HepB-BD introduction to reach births outside health facilities
Sri Lanka	1995	245	Community-based survey in Gampaha district	5–9	4.9 [30]	5–6	0.8b	72,579	410,105	Document vaccine impact (serosurvey)
Timor-Leste	ND					5–6	2.7b	3813	24,359	Increase HepB3 and HepB-BD coverage, evaluate HepB-BD introduction
SEAR					3.9c	5–6 yrs	1.1d	2,563,873	15,999,976

HBV: hepatitis B virus; HepB: hepatitis B vaccine; HBsAg: hepatitis B surface antigen; HH: household; HepB-BD: hepatitis B vaccine birth dose; HepB3: 3-dose series of hepatitis B vaccine; SEAR: South-East Asia Region; ND: no data.

^aUnpublished report.

^bEstimates of HBsAg from mathematical modeling calculated for each country among 5 year olds in 2015.

^cRegional pre-vaccine prevalence estimated as a weighted average of HBsAg prevalence in each country adjusted to surviving infant cohort size in 2000. For countries with multiple studies, a median estimate was calculated.

^dRegional post-vaccine prevalence among children aged 5 years estimated as weighted average of HBsAg prevalence in each country adjusted to surviving infant cohort size in 2015. Goldstein model HBsAg prevalence estimates were used unless the country had a nationally representative post-vaccine impact serosurvey.