Hepatitis E Virus: Hepatitis is a general term meaning inflammation of the liver. HEV is found in highest concentrations in blood and in lower concentrations in other body fluids. Hepatitis is a disease that can be caused by a variety of different viruses such as hepatitis A, B, C, D and E. Hepatitis E is caused by infection with the hepatitis E virus, a non-enveloped, positive-sense, single-stranded RNA virus. HEV is transmitted via the faecal-oral route. Hepatitis E is a waterborne disease, and contaminated water or food supplies have been implicated in major outbreaks. Consumption of faecally contaminated drinking water has given rise to epidemics; the risk factors for HEV infection are related poor sanitation in large areas of the world, and HEV shedding in faeces. Human hepatitis E has been transmitted under laboratory conditions to various species of primates, domestic pigs, lambs and laboratory rat’s .Person-to-person transmission is uncommon. There is no evidence for sexual transmission or for transmission by transfusion. The highest rates of infection occur in regions where low standards of sanitation promote the transmission of the virus. Hepatitis E should be suspected in outbreaks of waterborne hepatitis occurring in developing countries, especially if the disease is more severe in pregnant women .the incubation period following exposure to HEV ranges from 3 to 8 weeks, with a mean of 40 days. The period of communicability is unknown. There are no chronic infections reported. Typical signs and symptoms of hepatitis include jaundice (yellow discoloration of the skin and sclera of the eyes, dark urine and pale stools), anorexia (loss of appetite), an enlarged, tender liver (hepatomegaly), abdominal pain and tenderness, nausea and vomiting, and fever. There are no special medicines or antibiotics that can be used to treat a person once the symptoms appear; the only treatment is supportive care.

 

Methodology: Taqman Real time PCR assay

Clinical Use:

  • Assess viral measured by changes in the HEV RNA levels
  • Assess prognosis and early diagnosis for better patient cure
  • Confirm active hepatitis E virus (HEV) infection In patient

Screening:

  • persons residing in areas where extended community outbreaks exist
  • international travelers to regions of the world where HEV is endemic
  • persons who have chronic liver disease
  • possibly persons working with non-human primates, pigs, cows, sheep and goats
  •    All pregnant women
  • HIV-positive persons

Surveillance and Control

Surveillance and control procedures should include:

  • provision of safe drinking water and proper disposal of sanitary waste
  • monitoring disease incidence
  • determination of source of infection and mode of transmission by epidemiologic investigation
  • detection of outbreaks
  • spread containment
Performed:  Every day
Reported: 2-3 days

Specimen Required: Blood, serum, plasma, Collect in: Lavender (EDTA), pink (K2EDTA), or serum separator tube. Stability collection to initiation of testing On Cells: Ambient: 4 hours; after separation from cells: Refrigerated: 48 hours; Frozen at -20°C: 72 hours; Frozen at -70°C: 4 months. Do not thaw avoid repeated freezing and thawing

NOTE-Samples should be collected during the viraemic phase for the presence of viruses during the active infection. In case of non viraemic phase stool sample is most preferred sample.
Specimen Preparation: Separate serum or plasma from cells within 24 hours.

 

Storage/Transport Temperature: Frozen-20 0C. Refrigerate specimens at 2°C-4°C.

Unacceptable Conditions:  Heparinized specimens, Hemolysis sample, Quantity not sufficient for analysis, specimen grossly contaminated, specimen too old, frozen whole blood specimen, specimen leaky or tube broken.

 

Interpretation: This test can quantitate/detect Hepatitis E Virus RNA over the linear range 80-107 copies/mL. However this does not mean that lower copies or higher copies cannot be detected. The lower copies can be detected in some cases. This is a limitation of the currently available extraction systems. A negative result does not preclude the presence of HEV infection because results depend on adequate/proper patient sample storage and transportation as RNA is fragile and thermo labile, absence of inhibitors and sufficient RNA to be detected. Hepatitis E is a viral disease, and as such, antibiotics are of no value in the treatment of the infection. There is no hyperimmune E globulin available for pre- or post-exposure prophylaxis.

The result of this test must always be correlated with clinical status and history of the patient and other relevant data and   should not be used alone for the interpretation.   

Note: The test is intended for use in conjunction with clinical presentation and other laboratory markers as an indicator of disease prognosis.

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