HAV Structure and Types
Hepatitis A computer virus or HAV is a single - stranded with positive - polarity RNA computer virus , which belong to the genus Hepatovirus of the Picornaviridae family . The virus is a non - enveloped and icosahedral symmetry shape with a diameter ranges from 27 to 32 nanometre in size . So far , seven HAV genotypes have been identified by the experts . Four genotypes ( I , II , III , and VII ) are of human blood , and three ( IV , V , VI ) are of simian rootage . Genotypes I and III are the most prevalent genotype isolated from humans .
Hepatitis A virus Stability
HAV in - vitro culture demand a foresighted adaptation menses . It rarely create cytopathic gist because the HAV echo period is a dull process in the electric cell culture medium . However , it is stable in the environs for a month and it is more resistant to warmth . Physically deactivation involve heating of foods to more than 85 ° coulomb for 1 min and disinfection of surfaces require 1 minute of contact with a 1:100 dilution of sodium hypochlorite .
How Do You Diagnose Hepatitis A?
Detection of HAV-Specific Antibodies
The humoral immune response has a significant persona in the diagnosing of HAV contagion and the specialisation of hepatitis A from other types of viral hepatitis . There are a identification number of commercially available assay for the detection of antibodies against HAV infection . IgM antibody is only present in the blood following an acuate hepatitis A contagion . It is detectable from 1 to 2 workweek after the initial infection and persists for up to 14 weeks . Diagnostically , IgM anti - HAV has been used as the chief marking of acuate infection . The presence of IgG antibodies in the blood means the acute stage of the illness has pass and the person is immune to further infection . IgG antibodies to HAV are also found in the blood following vaccination , and trial for exemption to the computer virus are base on the detection of this antibody .
Immunological and Biochemical Techniques for Hepatitis A Virus Diagnosis
A act of method have been used to detect this virus - specific antibody such as radioimmunoassay , immunochemical staining , enzyme - yoke immunosorbent assay , immunoblotting , and battery-acid blot immunogold filtration . In the course of the piercing stage of the contagion , the liver enzyme alanine transferase is present in the roue at grade much higher than is normal . Alanine transaminase run is to support the HAV contagion and its liver disease or injury .
Microscopic Analysis
Hepatovirus A can survive in the blood and fecal matter of infected people up to 2 weeks before the clinical illness develops . HAV can be visualise in fecal extracts by electron microscopy . During outbreaks , the electron microscopy microscopic analysis could be a helpful proficiency for sensing of HAV virus in water sample and fecal extract .
Molecular Detection
Hepatitis A virus nucleic acid ( genetic material ) detective work techniques are more sensitive than biochemical and immunoassays for the viral antigen to find HAV in samples of unlike origins . It is commonly done with the help of Polymerase range of mountains reaction ( PCR ) . Clinical specimen , environmental samples , and food sample can be used for HAV detection during irruption . Amplification of viral RNA by RT - PCR ( Reverse Transcriptase - PCR ) is currently the most tender and widely used method for detection of HAV RNA .
Treatment for Hepatitis A Virus
There is no specific treatment at present for HAV transmission . The human organic structure will top the hepatitis A computer virus on its own and in most of the showcase , the liver heals within six month with no go damage . Rest , fluid intake , avoid alcohol , clean hygiene , and mild diet can recover somebody which may take several weeks or calendar month . Hepatitis A can be foreclose by inoculation , secure hygienics , and right sanitation . The CDC - USA recommends a hepatitis A vaccinum for the travel along individuals .
Also Read :
