Retrospective Review of Documentation Practices of Hepatitis B Immunoglobulin, Birth Dose, and Vaccination at the Hospital of Birth, in Thai Nationals and Migrants in Northern Thailand

Background: Vaccination remains the mainstay of prevention of hepatitis B virus (HBV) including birth dose and hepatitis B immunoglobulins (HBIGs). National estimates of vaccination coverage exclude migrants. The objective of this study is to investigate documentation practices of HBV-related infant vaccinations in Northern Thailand including migrants.

Methods: This is a retrospective review of hospital records of women who birthed infants in 2015 at Maharaj Nakorn Hospital, Chiang Mai (CM) or on the Thailand-Myanmar border, Tak.

Results: Of 2522 women, 987 were from CM (861 Thai nationals, 126 migrants) and 1535 were from Tak (651 Thai residence and 884 Myanmar residence). In CM, documentation for the birth dose vaccine (999 of 999, 100%) and HBIG was complete. In Tak, documentation was 1441 of 1549 (93%) for birth dose and 26 of 34 (76.5%) for HBIG, with missed opportunities including home delivery, delay in obtaining hepatitis B e-antigen status, and limitations of the records. Expanded Program of Immunization (EPI) documentation of 3 follow-up vaccinations dwindled with subsequent doses and distance, and complete documentation of 3 HBV EPI vaccines at the hospital of birth was low, 41.5% (1056 of 2547), but equitable for Thai or migrant status.

Conclusions: This review provides strong support for excellent documentation of HBIG and birth dose vaccination in urban and rural settings, and in migrants, consistent with Thailand's vaccination policy and practice. Documentation of the 3 HBV EPI at the hospital of birth decreases with sequential doses, especially in families further away. Innovative data linkage is required to prove coverage and identify gaps.