Hepatitis B and C乙型和丙型肝炎.docxVIP

Hepatitis B Definition Hepatitis B is inflammation of Liver caused by the hepatitis B? HYPERLINK /csr/disease/hepatitis/whocdscsrlyo20022/en/index7.html \l virus virus?(HBV) HBV is an enveloped? HYPERLINK /csr/disease/hepatitis/whocdscsrlyo20022/en/index7.html \l virus virus?containing a partially double stranded, circular DNA? HYPERLINK /csr/disease/hepatitis/whocdscsrlyo20022/en/index7.html \l genome genome, and classified within the family  HYPERLINK /csr/disease/hepatitis/whocdscsrlyo20022/en/index7.html \l hepadnavirus hepadnavirus Classification Acute Hepatitis (95%) Newly acquired infection Affected individuals notice symptoms approximately 1 to 4 months after exposure to the virus Symptoms resolve over weeks to months and they are cured of the infection Chronic Hepatitis (5%) Hepatitis B virus tests (HBsAg+) are positive after 6 months Infection with HBV that last longer than 6 month. Once infected, never go away. Might progress to develop Liver cirrhosis and hepatocellular carcinoma. Fatal The transition from acute hepatitis B to chronic hepatitis B signifies a failure of the immune response to eradicate the virus. Incubation Period The incubation period is usually 45-180 days with an average of 60-90 days. Transmission routes Blood and blood products Needle stick injuries Hepatitis B is highly infectious Sharing of needles among IV drugs abuser Sexual contacts Almost all the body fluids consists the protein Seminal fluid may contain of the virus Vertical transmission Vertical transmission from maternal to child during delivery through the birth canal Risk Factor High risk sexual behaviour Unprotected sex with more than one partner Unprotected sex with someone whos infected with hbv Sexual contact with same gender Share needles during intravenous (IV) drug use Share a household with someone who has a chronic HBV infection Occupation exposes to human blood Contaminated blood products Contaminated surgical equipment Receive hemodialysis for e