Hepatitis Virus Infections
Assistant Prof Botany epta Liver, itis *Infections The composition of the word tells that virus causes the inflammation (nfection) of liver But the information on the exact nature of hepatitis viruses is limited since the organisms multiply only in humans, although, the infectious nature of disease and its cause has been long recognized The viruses are responsible for m cases of hepatitis (nflammation of liver) rype A hepatitis (HAV), type B hepatitis (HBV) and type Chepatius (HCV The disease caused by HAV was formally known as infectious hepatitis, while HBV and HCV are serum hepatitis These both types B and Care very dangerous as compared to HAV, Type A hepatitis is also called jaundice, which can be cured without treatment or tellcebit therapy, while the viruses of type B and C cause great danger because they damage liver and blood cells of human. HCV causes the shnnkage of liver which is called cirrhosis or cancer of liver in whach liver is completely functionless and leads to death of a human, The effect of invasion by such viruses varies from an intangible infection to sever liver necross and death. Fataliry rates from reported cases range from 20-60% for hepatitis B and C, while about 1% for hepatitis A A fourth type of viral hepatitis has recently been described, it is caused by an agent designated as non A, non B, non CNANBNC. The particle is called delta virus Transmission ral transmission of hepatitis A, as through food and water, is the most common mode. While blood is the parental route of entry in human body for Hepatitis B and C While the parental route of entry in human body of B and C is blood. So infections of B and Care transmitted by blood transfusion, contaminated h needles contaminated instruments such as razors or used needles. While the cread of HAv through parental transmussion is rare The viruses (H HC) can be spread from person to person even m intensive care as pediatric or surgical wards ands heamodialysis units by means of infective secretions. Recently oral, veneral and neonatal transmission for the type B and Chas been observed Laboratory Diagnosis The clinical feature of three types of hepatitis virus causes the liver diseases. The tests of liver function ie. LFT do not differentiate the causative agents, but provide information only on the basis of hypatocellular injury elevated glumatic oxaloacetic (SGO) and (SGPT) Transaminases are common in all three hepatitis A, B and C while type B C differentiate from A by the presence of hepalilis B, C surface anugen (HBCs Ag) un the blood pauent with type B, C virus. The surface antigen is present during the premature stage of disease or early stages of illness in all patients, but 5 to 10% of them are detectable after four months or one to two years. To detect HBSAGHCsAg, we use sensitive techniques of radioimmunoassyx or Polymerase chain reaction (PCR), It can be detected by complement fixation norescent antibody techniques or electron microscopy, HBs. HCs Ag when active is high, so sera can be obtained from patients with acute or chronic progressive hepatitis. HBsHCsAg abundantly received from blood donors and patients who have received multiple blood transfusion. The serum antibody against HAv can be demonstrated by complement fixation unmune adherence heamagglutination and radio-immunoassay, while against HAV antibodies remain detectable in serum for many years after an initial infection. Immunity Antibodies are activated through vaccination against HBSAg which provide partial or complete immunity to human beings while for HCV there is no any vaccine but only strict care is needed from injury, razor and blood transfusion HAV is not as dangerous as compared to B and C. Prevention and Control The dissemination of hepatitis viruses can be minimized by strict adherence to personal hygiene, testing of blood transfusion for careful surveillance by public health agencies and broad educational programs Eliminating commercialism in obtaining donor blood is a goal of federal public health agencies in United States. Blood from paid donors carries a high risk for hepatitis The immune serum globulin (ISG) can be used to reduce the severity of hepatitis A, B, and C. A dose 0.02 ml kg of body weight is recommended immediately upon possible exposure to HAV. Passive immunization with 0.05 to 0.07 ml of ISG per kg of body weight is recommended to a large inoculation of HBV, while for HCV only strict care from blood transfusion, sexual contacts and use of the razors recommended.