Socioeconomic inequality in Hepatitis B vaccination of rural adults in China.

Hepatitis B (HB) vaccination is the most effective way to prevent HB virus infection. While measures taken to control the prevalence of HB have achieved significant results, HB prevalence in rural China among adults remains problematic. This study sheds new light on the determinants of HB vaccine uptake and its inequality according to socioeconomic status in rural areas of China. We interviewed 22,283 adults, aged 18-59 years, from 8444 households, in 48 villages from 8 provinces. Vaccination status was modeled by using two logistic models: whether take at least one HB vaccine and whether to complete the entire vaccination regime. The Erreygers' concentration index ([Formula: see text]) was used to quantify the degree of inequality and the decomposition approach was used to uncover the determinants of inequality in vaccine uptake. We found that the coverage rate of HB vaccination is 20.2%, and the completion rate is 16.0%. The [Formula: see text] of at least one dose (0.081) and three doses (0.076) revealed a substantial pro-rich inequality. Income contributed the largest percentage to HB vaccination inequalities (52.17% for at least one dose and 52.03% for complete vaccinations). HB awareness was another important cause of inequality in HB vaccination (around 30%). These results imply that rich had a greater tendency to vaccinate and inequality favouring the rich was almost equal for the complete three doses. While the factors associated with HB vaccination uptake and inequalities were multifaceted, income status and HB awareness were the main barriers for the poor to take HB vaccine by adults in rural China.