The virus can be passed from mothers who carry it to their babies during childbirth or from a family member to the infant in early childhood. The virus can also be transmitted through transfusions of contaminated blood and blood products contaminated with it, and through the use of contaminated injection equipment during medical procedures, and drug use by injection. The hepatitis B virus also poses a risk to health care providers who are accidentally exposed to the needles that they take while providing health services to those infected with the virus.