Ventricular Septal Defect Causes No one knows what causes ventricular septal defects, but they probably come from a malformation of the heart that occurs while the infant is developing in the womb. There may be just one hole or several holes in the septum.
Definition. Hepatitis B is a potentially serious form of liver inflammation due to infection by the hepatitis B virus (HBV). It occurs in both rapidly developing (acute) and long-lasting (chronic) forms, and is one of the most common chronic infectious diseases worldwide. Contact with infected blood is a common means of transmitting hepatitis B. 2  One way this may happen is by being stuck with a needle. 3  Both health care workers and those who inject drugs into their veins are at risk in this way. 4  Having sex with a person infected by HBV is an important risk factor (especially anal sex).
Hepatitis B is a virus which is carried in the bloodstream to the liver. It can then affect and damage your liver. The exact number of people infected is not known. In the UK around 1 person in 350 is thought to have persistent (chronic) hepatitis B infection.