Identified methods of transmission include contact with blood, blood transfusion (now rare), unsanitary tattoos, sex (through sexual intercourse or contact with bodily fluids), or mother-to-child by breast feeding; there is minimal evidence of transplacental crossing. However, in about half of cases the source of infection cannot be determined. Blood contact can occur by sharing syringes in intravenous drug use, shaving accessories such as razor blades, or touching wounds on infected persons. Needle-exchange programmes have been created in many countries as a form of prevention.Patients with chronic hepatitis B have antibodies against the virus, but not enough to clear the infected liver cells. The continued production of virus and countervailing antibodies is a likely cause of the immune complex disease seen in these patients. A vaccine is available to prevent infection for life. Hepatitis B infections result in 500,000 to 1,200,000 deaths per year worldwide due to the complications of chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). Hepatitis B is endemic in a number of (mainly South-East Asian) countries, making cirrhosis and hepatocellular carcinoma big killers. There are eight treatment options approved by the U.S. Food and Drug Administration (FDA) available for persons with a chronic hepatitis B infection: alpha-interferon, pegylated interferon, adefovir, entecavir, telbivudine, lamivudine, tenofovir disoproxil and tenofovir alafenamide with a 65% rate of sustained response. Hepatitis C
Hepatitis C (originally "non-A non-B hepatitis") is caused by hepatitis C virus (HCV), an RNA virus of the family Flaviviridae.
In some regions, such as the western United States, wildfires are responsible for an increase in burn injuries. Wildfires can suddenly shift due to changing wind directions, making it harder for firefighters and eyewitnesses to avoid getting burned. If clothing catches fire, third-degree burn can develop in a matter of just a few seconds. Hot objects
Solid objects that are hot can also cause contact burns, especially in children, who may intentionally touch things they dont know are too hot to touch. Such burns imprinted on the skin usually form a pattern that resembles the object. Sources of burns from solid objects include ashes and coal, irons, soldering equipment, frying pans and pots, oven containers, light bulbs, and exhaust pipes. Pathophysiology
There are three (or sometimes four) degrees of burns, in ascending order of severity and depth. For more information, see Signs and symptoms. According to Jacksons thermal wound theory, there are three zones of major burn injury. Zone of coagulation is the area that sustained maximum damage from the heat source. Proteins become denaturated, and cell death is imminent due to destruction of blood vessels, resulting in ischemia to the area. Injury at this area is irreversible (coagulative necrosis & gangrene) 
Zone of stasis surrounds the coagulation area, where tissue is potentially salvageable. This is the main area of focus when treating burn injuries. Zone of hyperemia is the area surrounding the zone of stasis. Perfusion is adequate due to patent blood vessels, and erythema occurs due to increased vascular permeability.