======Hepatitis B======

=====Serologies=====

^  Test  ^^^  Interpretation  ^  Vaccination  ^
^  HBsAg  ^  HBsAb  ^  HBc Ab  ^  :::  ^  :::  ^
| - | - | - | Susceptible | Vaccinate |
| - | + | - | Immunized | Not indicated |
| - | + | + | Immune due to natural infection | Not indicated |
| + | - | + \\ IgM + | Acutely infected | Not indicated |
| + | - | + \\ IgM - | Chronically infected | Not indicated |
| - | - | + | Equivocal | Clinical judgment |


  - May be distantly immune, but the test may not be sensitive enough to detect a very low level of anti-HBs in serum
  - May be susceptible with a false positive anti-HBc
  - May be chronically infected and have an undetectable level of HBsAg present in the serum
  - May be passive transfer of anti-HBc to infant born to HBsAg-positive mother
  - May be recovering from acute HBV infection and detectable anti-HBs has not yet appeared