How hepatitis B affects each person is very complex, but in general, young children are much more likely to develop chronic hepatitis B once exposed.

This table shows what is likely to happen, depending on how old you are when you are exposed to hepatitis B.

Age exposed to hepatitis B

Acute hepatitis B

Chronic hepatitis B

Infants (under 1 years old)

Most will not get any acute hepatitis B symptoms

90% will get chronic (lifelong) hepatitis B

Young children (aged 1 to 6 years old)

Most will not get any acute hepatitis B symptoms

30% will get chronic (lifelong) hepatitis B

Adults or older children (over 6 years old)

Many will get acute hepatitis B symptoms

Less than 5% will get chronic (lifelong) hepatitis B

Find out more about hepatitis B vaccination

References

WHO. (2018, July 18). Hepatitis B. Retrieved from World Health Organization.

Updated 11 December 2020