Hepatitis B (HBV) is a viral infection that affects the liver and is spread by direct contact with infected blood or other body fluids. Typical symptoms of hepatitis B usually appear 90 days after infection and may include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, pale stools, joint pain, and jaundice (yellowing of the skin or eyes).(1) About half of infected adults show symptoms, while many children under five do not.(2)
Although most acute hepatitis B infections do not become chronic, if the infection persists for six months or more without resolution, it can progress to chronic liver disease and liver cancer.(3)
Hepatitis B is diagnosed by a blood test. In acute stages, a hepatitis B surface antigen (HBsAg) can be detected, which persists from one week to nine weeks post-infection. Those who survive the infection develop hepatitis B surface antibodies (HBsAb), which are detectable in the blood. These tests can take up to six months to indicate whether the infection has resolved or become chronic.(4) Those who recover from an acute infection and clear the virus acquire permanent immunity.(5)
Hepatitis B is not considered highly contagious. Transmission occurs primarily through blood and other body fluids, such as semen and vaginal secretions.(6) It is not spread by sneezing, kissing, sharing food or utensils, or breastfeeding.(7) Transmission can often occur asymptomatically.(8)
Those at increased risk of contracting hepatitis B include injection drug users, individuals who have sex with infected people, sexually promiscuous adults, residents and staff of detention facilities, healthcare workers exposed to blood, hemodialysis patients, and newborns from infected mothers(9).
The risk of transmission of hepatitis B from mother to newborn is low, mainly due to routine prenatal screening of pregnant women for hepatitis B. Newborns of mothers who are positive or whose status is unknown are treated with immunoprophylaxis, including hepatitis B immune globulin (HBIG) to prevent transmission.(10)
