RNA Viruses: Hepatitis A, C, and D

RNA Viruses

• This section covers several RNA viruses, including their diseases, transmission methods, and impacts.

Hepatitis A Virus (HAV)

• Disease: Hepatitis A
• Transmission: Fecal-oral route via contaminated food/water or close contact.
• Impact: Causes acute liver inflammation leading to jaundice, fever, fatigue, and abdominal pain, but not chronic disease.
  • Rare cases can cause fulminant hepatitis which is life-threatening.

Hepatitis C Virus (HCV)

• Disease: Hepatitis C
• Transmission: Bloodborne, including unsafe injections, transfusions, and sexual contact.
• Impact: Results in chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC).

Hepatitis D Virus (HDV)

• Disease: Hepatitis D
• Transmission: Bloodborne, including unsafe injections, blood transfusions, sexual contact, and perinatal transmission.
• Impact: Causes severe liver diseases like Hepatitis D, cirrhosis, and hepatocellular carcinoma; its impact depends on co-infection with Hepatitis B Virus (HBV).

Hepatitis E Virus (HEV)

• Disease: Hepatitis E
• Transmission: Fecal-oral, especially through contaminated water.
• Impact: Can lead to acute liver failure, which is especially dangerous for pregnant women.

Dengue Virus (DENV)

• Disease: Dengue Fever
• Transmission: Aedes mosquito bites.
• Impact: Causes fever, hemorrhagic fever, and shock syndrome.

Rift Valley Fever Virus (RVFV)

• Disease: Rift Valley Fever
• Transmission: Mosquito bites and contact with infected animals.
• Impact: Manifests as hemorrhagic fever, encephalitis, and can cause livestock loss.

Chikungunya Virus

• Disease: Chikungunya fever
• Transmission: Aedes mosquito bites
• Impact: Includes severe joint pain, fever, and arthritis.

Zika Virus

• Disease: Zika Fever
• Transmission: Aedes mosquito bites and sexual contact
• Impact: Characterized by birth defects, including microcephaly, and Guillain-Barré syndrome.

West Nile Virus (WNV)

• Disease: West Nile Fever
• Transmission: Culex mosquito bites
• Impact: Causes fever, encephalitis, and neurological damage.

Crimean-Congo Hemorrhagic Fever Virus (CCHFV)

• Disease: Hemorrhagic Fever
• Transmission: Tick bites and contact with infected animals
• Impact: It has a high fatality rate and causes severe hemorrhage.

Ebola Virus

• Disease: Ebola Virus Disease
• Transmission: Contact with infected body fluids or animals
• Impact: Causes severe hemorrhagic fever and has a high mortality rate.

Marburg Virus

• Disease: Marburg Hemorrhagic Fever
• Transmission: Contact with infected body fluids or animals
• Impact: Causes hemorrhagic fever with a high fatality rate.

Poliovirus

• Disease: Poliomyelitis
• Transmission: Fecal-oral route.
• Impact: Can result in paralysis and disability.

Measles Virus

• Disease: Measles
• Transmission: Via respiratory droplets.
• Impact: Causes severe fever, rash, and complications such as pneumonia and encephalitis.

Rotavirus

• Disease: Gastroenteritis
• Transmission: Fecal-oral.
• Impact: Leads to severe diarrhea, particularly in children.

Lassa Virus

• Disease: Lassa Fever
• Transmission: Through contact with rodent excreta or infected individuals.
• Impact: Results in hemorrhagic fever and has a high mortality rate.

DNA Viruses

• This section outlines the different DNA viruses, the diseases they cause and how they are transmitted.

Hepatitis B Virus (HBV)

• Disease: Hepatitis B
• Transmission: via bloodborne, sexual, and vertical means
• Impact: Causes chronic liver disease and hepatocellular carcinoma.

Herpes Simplex Virus (HSV-1 and HSV-2)

• Disease: Oral and genital herpes
• Transmission: Through direct contact with lesions or secretions
• Impact: Causes painful blisters and potential neonatal infections.

Varicella-Zoster Virus (VZV)

• Disease: Chickenpox and shingles
• Transmission: Through respiratory droplets and contact
• Impact: Causes rash, pain, and nerve complications.

Human Papillomavirus (HPV)

• Disease: Warts and cervical cancer
• Transmission: Through direct contact and sexual transmission
• Impact: Leads to genital warts and cancers.

Cytomegalovirus (CMV)

• Disease: CMV infections
• Transmission: Through body fluids.
• Impact: can cause congenital infections and complications in immunocompromised patients.

Epstein-Barr Virus (EBV)

• Disease: Infectious mononucleosis
• Transmission: Through saliva
• Impact: Causes fever, fatigue, and potential lymphoma.

Adenovirus

• Disease: Respiratory and gastrointestinal infections
• Transmission: Spreads through respiratory and fecal-oral routes.
• Impact: Results in cold-like symptoms and diarrhea.

Smallpox Virus

• Disease: Smallpox
• Transmission: Spreads through respiratory droplets and contact.
• Impact: It had a high mortality rate before its eradication.

Parvovirus B19

• Disease: Fifth Disease
• Transmission: Through respiratory and bloodborne routes
• Impact: Causes rash and anemia.

Monkeypox Virus

• Disease: Monkeypox
• Transmission: Through contact with infected animals or humans
• Impact: It causes rash and systemic symptoms.

Tumor Viruses

• This section details various tumor viruses, categorized by DNA and RNA types, and includes information on diseases, transmission, impact, and prevalence.

DNA Tumor Viruses

• This refers to tumor viruses that are DNA-based.

Epstein-Barr Virus (EBV)

• Type: DNA
• Transmission: via saliva, close contact, and blood transfusions
• Impact: Associated with Burkitt's lymphoma, nasopharyngeal carcinoma, and Hodgkin's lymphoma
• Prevalence: Highly prevalent in Africa and the Middle East, particularly associated with endemic Burkitt's lymphoma in children.

Human Papillomavirus (HPV)

• Type: DNA
• Transmission: Via sexual contact and perinatal transmission
• Impact: Causes cervical, anogenital, and oropharyngeal cancers.
• Prevalence: Common in Sudan and other African countries causing High cervical cancer incidence due to limited vaccination and screening programs.

Hepatitis B Virus (HBV)

• Type: DNA
• Transmission: Transmitted through bloodborne routes (unsafe injections, transfusions, and perinatal).
• Impact: Chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC).
• Prevalence: Endemic in Africa and the Arab world, including Sudan w high rates of chronic infections.

Merkel Cell Polyomavirus (MCV)

• Type: DNA
• Transmission: spreads via skin contact.
• Impact: Causes Merkel cell carcinoma, an aggressive skin cancer.
• Prevalence: Rare in individuals but found in immunosuppressed individuals.

Kaposi’s Sarcoma-Associated Herpesvirus (KSHV)

• Type: DNA
• Transmission: saliva and sexual contact
• Impact: Causes Kaposi’s sarcoma, common in HIV/AIDS patients.
• Prevalence: Highly associated with endemic Kaposi’s sarcoma in Sub-Saharan Africa, including Sudan.

RNA Tumor Viruses

• This defines RNA-based tumor viruses

Hepatitis C Virus (HCV)

• Type: RNA
• Transmission: Via bloodborne routes (unsafe injections, transfusions, and sexual contact)
• Impact: Chronic liver disease, cirrhosis, hepatocellular carcinoma (HCC).
• Prevalence: significant public health issue in Sudan and Egypt attributed to healthcare-associated transmission.

Human T-cell Lymphotropic Virus Type 1 (HTLV-1)

• Type: RNA
• Transmission: blood transfusions, sexual contact and breastfeeding.
• Impact: Linked to adult T-cell leukemia/lymphoma (ATL).
• Prevalence: endemic in select African and Middle Eastern populations, including Sudan.

Human Immunodeficiency Virus (HIV)

• Type: RNA.
• Transmission: bloodborne, sexual contact, and perinatal transmission.
• Impact: linked to Kaposi's sarcoma, non-Hodgkin’s lymphoma, and cervical cancer.
• Prevalence: high in Sub-Saharan Africa, including Sudan, exacerbated by co-infections.

Other Cancer-Associated Viruses

• Additional viruses also linked to cancer development.

Schistosomiasis-Associated Viruses (HBV and HCV Co-Infection)

• Type: DNA and RNA
• Transmission: co-infections from schistosomes and viral exposure in waterborne settings.
• Impact: increased risk of bladder and liver cancers.
• Prevalence: Widespread in Sudan due to endemic schistosomiasis.

Simian Virus 40 (SV40)

• Type: DNA.
• Transmission: contaminated vaccines (historical concern).
• Impact: linked to mesothelioma and brain tumors.
• Prevalence: rare, related to historical incidents.

Cytomegalovirus (CMV)

• Type: DNA
• Transmission: through saliva, blood, or congenital means
• Impact: Associated with immunosuppression and glioblastoma
• Prevalence: Common among immunosuppressed populations in Africa and Middle East.

Rous Sarcoma Virus (RSV)

• Type: RNA
• Transmission: through animal studies in experimental models.
• Impact: to study cancer mechanisms.
• Prevalence: very rare but foundational in cancer biology.

Zika Virus

• Type: RNA
• Transmission: mosquito bites and potential sexual contact.
• Impact: Rarely associated with brain tumors due to neurological abnormalities
• Prevalence: occasional outbreaks in Africa and Middle East.

Ebola Virus

• Type: RNA
• Transmission: transmission: blood and bodily fluids of those infected.
• Impact: rare connections to immune irregularities and secondary malignancies.
• Prevalence: attention to outbreaks in West and Central Africa.

Rabies Virus

• Type: RNA.
• Transmission: transmission: animal bites.
• Impact: Rare links to neurological tumors under continuing conditions.
• Prevalence: Sudan, Africa, and the Arab region have sparse cases, especially in rural environments.

Prions related diseases

• Prion-related disorders.
• These include;
  • Bovine Spongiform Encephalopathy
  • Creutzfeldt-Jakob Disease.

Interferon

• A natural protein known as cytokine that belongs to glycoprotein group
• cells produce interferon and it assists the immune response by acting in response to challenges and inhibiting viral replication within host cells, inducing resistance of the host cells to infection from foreign agents such as a virus, parasite and even tumor cells.
• Interferon also activates the immune cells, such as NK cells and macrophages.

Gene therapy

• A virus is used to correct defective genes, e.g,. in Down's syndrome.