Acute hepatitis B infection can occur in fully vaccinated individuals when viral mutations evade antibody recognition. A new case report details how a 72-year-old man developed symptomatic infection despite possessing high post-vaccination antibody levels.
The patient presented with hepatomegaly and abnormal liver function. Laboratory testing confirmed acute hepatitis B with detectable HBV DNA. Crucially, serologic analysis showed protective anti-HBs antibodies remained present at 345 IU/L, ruling out simple vaccine nonresponse.
Genomic sequencing identified a D144A mutation in the S gene of HBV genotype A2. This specific mutation alters the surface antigen region targeted by vaccine-induced antibodies, facilitating immune escape. The patient reported no traditional risk factors for exposure.
Recovery was spontaneous without antiviral treatment. Liver enzymes and viral markers normalized within three months. Researchers suggest vaccination likely prevented progression to chronic disease despite the acute breakthrough.
Dutch surveillance data spanning two decades indicates such variants remain rare, representing only 3.5% of sequenced cases. However, findings reinforce that clinicians must consider hepatitis B in vaccinated patients presenting with acute hepatitis symptoms. Continued genomic monitoring remains essential to track strains with potential public health implications.