Hepatitis B in Poland in 2021.

In the second year of the COVID-19 pandemic, a gradual levelling of the sharp decline in the number of diagnosed chronic and UNK cases that occurred in 2020 was observed. In acute cases, a further decline in incidence was noted compared to 2020, but a smaller number of acute cases was most likely due to the lower effectiveness of surveillance during the COVID-19 pandemic, rather than from an improvement in the epidemiological situation. The vaccination coverage of children in the second year of life (born in 2020) with the third dose of HepB vaccine continued to decline, although slightly.