Virus Types and Infections PDF

# Virus ## 1. Papiloma - **Infection:** Viral infection that causes warts, condylomas and cancer - **Structure:** Circular capsid, icosahedral shape, DNA, enveloped - **Host Cell:** Mucoepithelial cells - **Transmission:** - Sexual Transmission (ETS) - Contact with lesion - **Examples:*...

# Virus ## 1. Papiloma - **Infection:** Viral infection that causes warts, condylomas and cancer - **Structure:** Circular capsid, icosahedral shape, DNA, enveloped - **Host Cell:** Mucoepithelial cells - **Transmission:** - Sexual Transmission (ETS) - Contact with lesion - **Examples:** - Cutaneous warts - Papilloma (pharynx, genitals, anus) - Cancer: HPV 16, 18 - **Treatment:** - Condyloma removal - Vaccine - Antivirals - **Diagnosis:** - PCR - Colposcopy/Pap smear - Lugol's test - **Genome:** Circular ## 2. Adenovirus - **Infection:** Viral infection that causes respiratory infections, hemorrhagic cystitis and conjunctivitis, gastroenteritis - **Structure:** Icosahedral shape, linear DNA, naked - **Host Cell:** Epithelial cells of the target tissue - **Transmission:** - Inhalation - Direct contact - Fecal-oral - **Examples:** - Acute viral infections - Pertussis (whooping cough) - Cystitis - Gastroenteritis - Meningitis/Conjunctivitis - **Treatment:** Oral vaccine for types 4 and 7 - **Capsids:** Highly resistant to gastrointestinal tract inactivation - **Virus persistence:** The virus persists in lymphoid tissue (tonsils, adenoids, Peyer's patches) - **Children:** Virus remains in children under 14 years old. ## 3. Herpes - **Infection:** Viral infection that causes painful ulcers or vesicles - **Structure:** Icosahedral shape, DNA, enveloped - **Epstein Barr:** - **Transmission:** Direct contact, airborne transmission - **Host Cell:** Mucoepithelial cells and neurons - **Examples:** - Fever blisters (oral herpes) - **Diagnosis:** Clinical - **Treatment:** Antiviral - **Herpes simplex virus type 2:** - **Transmission:** Sexual Transmission (ETS) - **Host Cell:** Mucoepithelial cells and neurons - **Examples:** - Genital herpes - **Diagnosis:** Clinical and PCR - **Treatment:** Antiviral - **Herpes simplex virus type 3:** - **Transmission:** Inhalation, direct contact - **Examples:** - Varicella-zoster (Chicken Pox) - Shingles - **Diagnosis:** Clinical - **Treatment:** Vaccination - **Herpes simplex virus type 4:** - **Transmission:** Saliva - **Examples:** - Infectious mononucleosis (kissing disease) - **Diagnosis:** PCR - **Treatment:** Antiviral - **Herpes simplex virus type 5:** - **Transmission:** Blood transfusion and transplantation - **Examples:** - Cytomegalovirus - **Diagnosis:** PCR - **Treatment:** Antiviral - **Herpes simplex virus type 6 and 7:** - **Transmission:** Direct contact - **Examples:** - Roseola - **Diagnosis:** PCR - **Treatment:** Antiviral - **Herpes simplex virus type 8:** - **Transmission:** Sexual Transmission (ETS) - **Examples:** - Kaposi's sarcoma - **Diagnosis:** PCR - **Treatment:** Antiviral - **Diagnosis:** Clinical examination, serologic testing, cytological examination (Tzanck smear) ## 4. Poxvirus - **Zoonosis:** - **Infection:** Viral infection that causes molluscum contagiousum, smallpox - **Structure:** Brick-shaped, large capsid, DNA, enveloped. - **Host Cell:** Epithelial cells, immune cells - **Transmission:** - Direct contact - Inhalation - **Examples:** - Molluscum Contagiosum: Causes warts - Smallpox: Pox rash - **Treatment:** - Vaccine for smallpox - Molluscum contagiousum: Removal via scraping. - **Replication:** Occurs in the cytoplasm - **Diagnosis:** - PCR - Viral culture - Electron microscopy - Serologic testing ## 5. Parvovirus - **Infection:** Viral infection that causes fifth disease (erythema infectiosum), anemia in adults - **Structure:** Icosahedral shape, DNA, naked - **Host Cell:** Red blood cells, cells of the bone marrow - **Transmission:** Inhalation - **Examples:** - Erythema infectiosum: Rash in children - **Treatment:** None usually required - **Diagnosis:** - Serologic testing - PCR - Examination for viral antigens - Hemogram - **Capsids:** Resistant to inactivation - **Transmission:** Occurs through the respiratory tract - **Disease severity:** Mild, similar to the flu - **Anemia:** Aplatic crisis occurs in people with anemia - **Chronic infection:** May occur in some people ## 6. Picornavirus - **Infection:** Viral infection that causes poliomyelitis, common cold. - **Structure:** Icosahedral shape, RNA, naked - **Replication:** Occurs in the cytoplasm - **Transmission:** - Poliovirus: Fecal-oral - Rhinovirus: Inhalation, direct contact - **Host Cell:** Epithelial cells, blood cells - **Examples:** - Poliomyelitis - Rhinovirus - Enterovirus - Heparnavirus - Cardiovirus - Aphtovirus - **Proteins:** VP1, VP4, VPg - **Zoonosis:** Can affect animals and humans - **Poliovirus:** - **Examples:** - Asymptomatic infection - Abortive poliomyelitis (mild disease) - Nonparalytic poliomyelitis (aseptic meningitis) - Paralytic poliomyelitis (major disease) - **Diagnosis:** - Cerebrospinal fluid analysis (CSF) - Virus culture - PCR - Serologic tests - **Treatment:** - Polio: Poliovirus vaccine - Rhinovirus: No specific treatment, symptom relief - **Family of viruses:** Infects humans and animals - **Disease spectrum:** Range in impact from common cold to poliomyelitis - **Key factors:** Serovar, infectious dose, tissue trophism, route of entry, host ## 7. Coronavirus - **Name origin:** Morphology of viral particles - **Infection:** Viral infection that causes the common cold, gastroenteritis, SARS (severe acute respiratory syndrome) - **Structure:** Enveloped helical shape, long RNA, plus strand RNA - **Host Cell:** Epithelial cells of the respiratory tract - **Transmission:** - Inhalation of respiratory droplets - **Replication:** Occurs in the rough endoplasmic reticulum - **Examples:** - Common cold - Gastroenteritis - Severe acute respiratory syndrome (SARS) - **Diagnosis:** - Clinical examination - PCR - Electron microscopy - **Treatment:** - Control of transmission - Symptom relief - Vaccines ## 8. Norovirus - **Infection:** Viral infection that causes gastroenteritis - **Structure:** Icosahedral shape, RNA, naked - **Types:** 100-16 genotype groups - **Host Cell:** Enterocytes - **Transmission:** Fecal-oral, contaminated water and food, vomit - **Resistance:** Tolerant to detergents, drying, acid - **Pathogenesis:** Viral replication - **Examples:** - Diarrhea - Nausea - Vomiting - Muscle cramps - **Incubation period:** 24 to 48 hours - **Duration:** 12 to 60 hours - **Diagnosis:** - Clinical examination - PCR - Immunoelectron microscopy - EIA - ELISA - Serologic testing - **Treatment:** - No specific therapy available - Symptom relief - **Resistance:** Tolerant to pH 3 and 60 degrees Celsius