Hepatotropic Viruses

Hepatitis A Viral (HAV) infection

1. This can be detected in the following samples:
   1. Feces
   2. Liver
   3. All body fluids (serum, other body fluids).
   4. These samples can be stored at 4 °C, and tissues may be stored at -20 °C.
2. Diagnostic tests are:
   1. Anti-HAV IgM.
   2. Anti-HAV IgG.

Hepatitis B viral (HBV) infection

1. This virus can be detected in the following samples:
   1. Serum
   2. Whole blood
   3. Liver
   4. Body fluids
   5. Store serum and body fluids at 4 °C and store tissue at -20 °C.
2. Diagnostic tests are:
   1. HB surface antigen.
   2. HB surface- antibody
   3. HBe antigen.
   4. HBe antibody.
   5. HBc-IgM antibody.
   6. HBc-antibody total (HBc-IgM and IgG).

Hepatitis C viral (HCV) infection

1. The virus can be detected in the following samples:
   1. Whole blood
   2. Serum
   3. liver tissue
   4. Body fluids
2. Diagnostic tests are:
   1. Anti-HCV antibody.
   2. PCR for HCV antigen.
   3. Serum, blood, and body fluids can be stored at 4 °C, and liver tissue at -20 °C.

Hepatitis Delta Virus (HDV) infection

1. The Hepatitis D virus is also called delta hepatitis. It was discovered in 1977.
2. A partially defective virus must enter HBV to infect hepatocytes.
3. So HBV will be present before the patient develops Hepatitis D infection.
4. HBV is needed as a helper to start the infection.
5. The Hepatitis D virus can be detected in the following samples:
   1. Whole blood
   2. Serum
   3. Liver tissue
6. Diagnostic tests are:
   1. Anti-D IgM.
   2. Anti-D IgG.

• Whole blood and serum can be stored at 4 °C, and liver tissues at -20 °C.

Hepatitis E virus (HEV)

1. It is the NANB virus, with incubation time, clinical signs and symptoms, and epidemiology similar to HAV infection.
2. HEV is thought to be a calicivirus.
3. HEV is a non-enveloped, single-stranded RNA virus.
4. Till 1994, no serological tests for HEV were available.
5. HEV diagnostic tests are:
   1. HEV antigen identified in hepatocytes.
   2. HEV can be identified in the stool by immunoelectron microscopy.
   3. Serum is positive for IgM anti-HEV antibodies, which are short-lived.
   4. Anti-HEV IgG was also found to appear immediately after IgM.

Other Viruses

Herpes Simplex (HSV) infection

1. Most cases are caused by HSV type 2, and there are significant numbers of HSV type 1.
2. This can be diagnosed by:
   1. Skin biopsy lesion
   2. Vitreous humor
   3. Cerebrospinal fluid (CSF)
   4. Serum
3. Diagnostic tests are:
   1. Cultural is the gold standard,
   2. HSV antigen 1.
   3. HSV antigen 2.

• Stored body fluids at 4 °C and tissue at -20 °C.

Cytomegalovirus (CMV) infection

1. CMV is a part of the herpesvirus group.
2. CMV infection is widespread, as serological evidence of infection varies from 30% to >90% of the population.
3. There is a lower incidence in the USA and Western Europe.
4. CMV infection is seen in:
   1. Fetal and early childhood.
   2. Young adults and late adolescents.
5. This can be diagnosed from:
   1. Whole blood
   2. Serum
   3. Urine
   4. Tissues
6. Diagnostic tests:
   1. Culture is the most sensitive method.
   2. CMV-IgM indicates the most recent infection.
   3. CMV-IgG indicates past infection.

• Store all fluids at 4 °C and tissues at -20 °C.

Epstein-Barr Virus (EBV) infection

1. EBV is a member of the herpes virus.
2. This can be diagnosed with the following samples:
   1. Whole blood
   2. Tissue
   3. saliva
3. Diagnostic tests are:
   1. Monospot heterophilic agglutination test.
   2. Viral capsid antigen-antibody test for IgM and IgG.
   3. EBV nuclear antigen (EBNA).
      1. EBNA-IgG
      2. EA-D

• Store the fluid at 4 °C and the tissue at -20 °C.

Human Immunodeficiency Virus (HIV-1)

1. This can be diagnosed by:
   1. Whole blood
   2. urine
   3. Body fluids
2. Diagnostic tests are:
   1. HIV antibody test by ELIZA.
   2. Western blot test.
   3. p24 antigen capture assay. This will detect before the seroconversion and also assess the progression of AIDS.
   4. Oral fluid kits for detecting HIV antibodies, such as Orasure, Orapette, and Omni Sal, are available.
   5. Urine for the HIV antibody test.

• Store fluids at 4 °C and tissue at -20 °C.

Human papillomavirus (HPV)

1. More than 50 human papillomavirus strains have been reported.
2. Most clinical manifestations are:
   1. Warts on the skin.
   2. HPV-1 is mostly associated with warts on the sole of the foot.
   3. Condylomata are papillary lesions in the genital area.
   4. HPV-2 is a nonplanter skin lesion.
   5. HPV-6 and II are found mostly in benign condylomatous lesions and low-grade cervical dysplasia (CIN I and II).
   6. HPV 16 and 18 are found in 80% to 95% of the patients with high-grade cervical dysplasia or carcinoma in situ (CIN III), and are also associated with a few cases of carcinoma of the penis.
3. This can be diagnosed from:
   1. Cervical smears.
   2. Biopsy or scrapings.
   3. Tissue from the anogenital area.
4. Diagnostic tests are:
   1. Colposcopy and Vinegar acetic acid will make the affected area appear white.
   2. A Pap smear will reveal abnormalities in the cells and identify virus-infected cells.
   3. Biopsy.
   4. HPV cervical test.
   5. DNA test (PCR, Southern blot hybridization).

• Store the tissue at -20 °C.
• It can be prevented by vaccination. It should be given before sexual activity.

Rotavirus Infection

1. Rotavirus is an RNA virus in the Reoviridae family.
2. It can infect birds as well as humans.
3. This is the most common cause of infectious diarrhea in infants and young children.
   1. It is quite common in the nursery and daycares.
4. The patient will have diarrhea, fever, and vomiting.
5. Peak season in the USA is winter, but it is equally distributed in tropical areas.
6. Its mode of spread is the feco-oral route.
7. How will you do the diagnosis?
8. This can be diagnosed from:
   1. Feces (isolate the nucleic acid)
   2. This can be stored at 4 °C.
9. Diagnostic tests are:
   1. Stool for rotavirus antigen.
   2. ELIZA

Varicella-Zoster Virus

1. Primary infection is Varicella (Chicken Pox).
   1. Reactivation leads to Herpes Zoster (Shingles).
2. Varicella-Zoster virus is a member of the Herpes group.
3. It spreads through direct contact via skin lesions or via droplet inhalation.
4. The incubation period is about 14 days, and ranges from 9 to 21 days.
5. The primary infection is Varicella (Chickenpox).
6. The period of skin rash lasts about 4 to 6 days.
7. Complications include:
   1. Pneumonia.
   2. Encephalitis.
   3. Reye’s syndrome.
8. Varicella during pregnancy may infect the fetus in around 5% to 10% of cases.
9. This can be diagnosed from:
   1. Whole blood.
   2. Skin Lesions.
   3. Diagnostic tests are:
      1. Usually, this is diagnosed by the clinician as a typical vesicular dermal lesion.
      2. Culture of the virus.
      3. PCR from the lesion.
      4. Serologic tests can be performed using fluorescent antibody staining.
      5. Zanck test, smear of the Varicella-Zoster lesion.

• Store fluids at 4 °C and tissues at -20 °C.

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