AbstractHepatitis Bis a viral infection from thefamily Hepadnaviridae that is spread worldwide and is found in both mammals andbirds. Eastern areas seem to be more prevalent to the infection due to not havingproper equipment. It is spread through body fluids such as blood and semen.When someone becomes infected they suffer from acute or chronic hepatitis B.
Symptoms vary between host and how long they have been infected. This disease isknown as the “silent killer” because when they become infected with hepatitis Bthey often show no symptoms until months later. Several vaccinations were licensedin late 1980’s and have drastically made the infection number over half. Hepatitis B The hepatitis B virus (HBV) is a small DNAvirus that has abnormal characteristics similar to retroviruses (6). HepatitisB has three different viral structures Dane particle, spherical, andfilamentous these can all be observed under an electron microscope (11). Ahepatitis B virus surface antigen (HBsAG) can be found on the surface of eachof these particles (11).
Therefore, spherical and filamentous particles arevery similar because they both have HBsAG and host-derived lipid which makesthem non-infectious (11). The complete virion is known as the Dane particle;the genome is an 42nm sphere, it is arelaxed circular, partially double-stranded DNA about 3.5 kb, and DNApolymerase that is surrounded by nucleocapsid; the nucleocapsid is thestructure that holds kinases proteins (11). It contains an outer envelope thatholds the surface antigen “HBsAG” (10). The DNA polymerase is used as reversetranscriptase in the replication cycle (11).
A unique characteristic abouthepatitis B cell structure is that it is asymmetric when connecting the twoprotein chains (11).Hepatitis B Classification (4)· Domain:unknown for viruses · Family:Hepadnaviridae· Genus:Orthohepadnavirus or avihepadnavirusesHepatitis B is a prototype of the virus of the family Hepadnaviridae (7). Viruses that fallunder this family are found in both mammals and birds (woodchucks, groundsquirrel, peking ducks and herons (6).
ETIOLOGY –If a person comes in contact withhepatitis B it can live outside of their body for up to seven days; if a personhas not been vaccinated in the past they have a high chance of the infectionentering there body and damaging their liver (1). When a person contractshepatitis B they suffer from acute or chronic illness. When experiencing acuteillness children under the age of five and immunocompromised adults rarely havevisible signs or symptoms (2,3). For this reason, HBV was given the name”silent infection” because infectedpeople where unknowingly spreading the virus because they had no visible signsof the disease (10).
Statistics showthat children older than five and adultshave a greater chance of developing symptoms that include: yellowing of theskin and/or eyes (Jaundice), vomiting, fever, nausea, loss of appetite, darkurine, fatigue, and joint pain (1,2,3). These symptoms often do not appear directly after being infected; it cantake between six weeks to six months after becoming infected before one startsto develop the signs of hepatitis B (2). When developing symptoms, it isunknown how long they may last. Symptoms could disappear within a few weeks orthe viral infection could last several months (3).
Therefore, about 5%-10% ofadults are unable to fight off the infection and experience symptoms lastinglonger than six months they are then diagnosed with chronic Hepatitis B (3,6). Severalpersons chronically infected suffer from liver disease, leading to cirrhosisand liver cancer (6). Once chronic Hepatitis B has developed in the body thereis not much left a person can do besides being regularly monitored by theirphysician, take medicine as prescribed, and avoiding alcohol and medicationsthat may cause additional liver damage. Today, thereare approximately 300 million people worldwide infected with HBV (1,2).Approximately 240 million of these patients live outside of the United States(2). People who live in populations such as Africa 6.1%, Asia 2.
0%, The PacificIslands 6.2%, Eastern Europe 1.6%, and The Middle east 3.3% are most impactedby Hepatitis B (3,5).
These countries are more prevalent because some do nothave to proper vaccinations and lack sterilization methods (2). Transmission of HBV occurs through human reservoirs; thereis a variety of ways that the disease can be spread between humans (2,5). Transmission of hepatitis B is generallymost common from having sexual intercourse with an infected partner, infectedmother to her baby at birth, sharing of contaminated needles and syringes, anddirect contact with blood or open sores (2,5). Transmission can also occurthrough medical and dental procedures, tattooing and through the use of razorsor other objects that can come in contact with infected blood (1). It isextremely important when traveling to consult with your doctor aboutprecautions to take in an area with high HBV rates (2).
Unfortunately,acute hepatitis B is difficult to treat because the virus can be mistaken asthe flu. During this stage doctors thrive to keep the patient comfortable andprovide them with adequate nutrients to keep them hydrated since they arelosing fluids every time they vomit or have a bowel movement (1). Therefore, ifyou are suffering with chronic hepatitis B they provide oral antiviralmedications that slow the process of your deteriorating liver.
Some of the morecommon oral medications prescribed include Entecavir and Tenofovir(1). For ayear of treatment these can vary from$400-$1500 which can make it difficult for people to afford the correcttreatment (1). In 1982, the first hepatitis Bvaccine became available in the United States (8). Recombinant DNA technology licensedtwo vaccinations a few years later. In 1986, their first hepatitis B vaccineRecombinant HB and their second vaccination Engerix B was licensed in 1989 (8).
Today these are the main hepatitis B vaccinations used in the United States. The two vaccines are 95% effective in protectingyour body form contracting this disease (1). These vaccines are safest and most effective form ofprevention; It consists of a series of three shots over the course of a sixmonth period that (2). Doctors recommendthat you receive the first vaccination within 24 hours of birth or as quicklyas possibly if you have not completed the required doses (8). Many schools anddaycare facilities throughout the UnitedStates are requiring the children to have complete the three step vaccinationbefore entry (8). Hepatitis B can spread quickly between children when dealingwith open wounds; in 1982 there were 8-15% of chronic hepatitis B reportedsince this prevention method has been available chronic hepatitis B in children has decreased toonly 1% (1 ).
Not only in children but adults too, before the vaccination eraabout 4.7% where infected compared to the 1.3% today; these numbers droppeddrastically after people began to take the series of vaccinations (1).