PAC548 Viruses

What type of virus is Cytomegalovirus (CMV)?

dsDNA Herpesvirus; enveloped; latent in monocytes; produces giant cells in skin.

How is CMV transmitted?

Transfusion, sexual contact, secretions (saliva/urine), intrauterine.

What disease is caused by CMV?

Mostly asymptomatic; mononucleosis; congenital abnormalities; colitis, pneumonia, retinitis in AIDS.

How is CMV diagnosed and treated?

PCR, blood stain for "owl's eye", pp65 antigen; treated with Ganciclovir or Valganciclovir.

What type of virus is Epstein-Barr Virus (EBV)?

dsDNA Herpesvirus; enveloped; latent in B-lymphocytes.

How is EBV transmitted?

Respiratory secretions, saliva.

What diseases are caused by EBV?

Infectious mononucleosis, Burkitt’s lymphoma, B cell lymphoma, nasopharyngeal carcinoma, hairy leukoplakia.

How is EBV diagnosed?

Heterophile antibody test (Monospot), IgM, atypical lymphocytes.

What type of virus is HHV-6 (Roseola)?

dsDNA Herpesvirus; enveloped; infects B and T cells.

What disease is caused by HHV-6?

Roseola Infantum: high fever then facial/truncal rash in infants; encephalitis/pneumonia in immunocompromised.

What type of virus is Herpes Simplex Virus 1?

dsDNA Herpesvirus; enveloped; latent in cranial sensory ganglia; forms giant cells.

How is HSV-1 transmitted and diagnosed?

Saliva, respiratory secretions; diagnosed by PCR, culture, Tzanck smear; treated with Acyclovir.

What disease is caused by HSV-1?

Gingivostomatitis, cold sores, keratoconjunctivitis, temporal lobe encephalitis.

What type of virus is Herpes Simplex Virus 2?

dsDNA Herpesvirus; enveloped; latent in lumbar/sacral ganglia; forms giant cells.

What disease is caused by HSV-2?

Genital lesions, meningitis, neonatal encephalitis; diagnosed/treated same as HSV-1.

What type of virus is Varicella-Zoster Virus (VZV)?

dsDNA Herpesvirus; enveloped; latent in sensory ganglia; forms giant cells.

What diseases are caused by VZV?

Chickenpox (varicella), shingles (zoster), pneumonia, Reye’s syndrome, postherpetic neuralgia.

How is VZV diagnosed and prevented?

PCR, Tzanck smear; Acyclovir; vaccine available for both chickenpox and shingles.

What type of virus is HPV?

dsDNA, non-enveloped; enters basal cells, expresses E6/E7 proteins that inactivate p53/RB.

How is HPV transmitted?

Skin-to-skin, vertical.

What disease does HPV cause?

Warts on skin/genitals; can cause cervical cancer.

How is HPV diagnosed and prevented?

Clinical, PCR for high-risk types; treated with Miquimod; Gardasil vaccine.

What type of virus is Molluscum contagiosum?

dsDNA Poxvirus; enveloped; enters through abrasion.

What disease does Molluscum contagiosum cause?

Cup-shaped papules near eyes or genitals.

What type of virus is Mpox (MPXV)?

dsDNA Poxvirus; enveloped.

How is Mpox transmitted and what are symptoms?

Direct contact or respiratory droplets; rash starting on face, fever, lymphadenopathy, encephalitis.

Is there a vaccine for Mpox?

Yes, smallpox vaccine provides some protection.

What type of virus is Coxsackie virus?

ssRNA (+), non-enveloped.

What diseases are caused by Coxsackie?

Hand-foot-mouth disease (A), myocarditis/pleurodynia (B), meningitis, flaccid paralysis.

What type of virus is Norovirus?

ssRNA (+), non-enveloped.

How is Norovirus transmitted and what does it cause?

Fecal-oral; gastroenteritis with nausea, watery diarrhea, low fever.

What type of virus is Rotavirus?

dsRNA, non-enveloped.

What diseases are caused by Rotavirus?

Severe gastroenteritis in children with dehydration, vomiting, watery diarrhea.

What type of virus is Poliovirus?

ssRNA (+), non-enveloped.

What disease is caused by Poliovirus?

Paralysis due to motor neuron death; post-polio syndrome.

What is the preferred Polio vaccine?

Salk (inactivated).

What type of virus is Hepatitis A?

ssRNA (+), non-enveloped; fecal-oral transmission.

What type of virus is Hepatitis B?

dsDNA, enveloped.

What diseases does HBV cause?

Jaundice, hepatocellular carcinoma; transmitted via blood, sexual contact, birth.

How is HBV diagnosed and prevented?

HBsAg and HBcAb test; HBIG post-exposure; vaccine available.

What type of virus is Hepatitis C?

ssRNA (+), enveloped.

What are the treatment options for HCV?

Peginterferon, antivirals, NS5A and RNA polymerase inhibitors.

What type of virus is Influenza?

ssRNA (–), enveloped; has HA and NA proteins.

What diseases does Influenza cause?

Myalgias, fever, sore throat, cough; neuraminidase aids mucus penetration.

What treatments and vaccines exist for Influenza?

Tamiflu, Relenza; killed and live vaccines (IM, nasal).

What type of virus is Rhinovirus?

ssRNA (+), non-enveloped.

What disease is caused by Rhinovirus?

Common cold: sneezing, nasal discharge, sore throat.

What type of virus is Adenovirus?

dsRNA, non-enveloped.

What diseases does Adenovirus cause?

Fever, conjunctivitis, pharyngitis, pneumonia.

What type of virus is SARS-CoV-2?

ssRNA (+), enveloped; spike protein binds ACE2 receptor.

What disease does SARS-CoV-2 cause?

COVID-19: fever, dry cough, anosmia, long COVID.

What treatments exist for COVID-19?

Antivirals, convalescent plasma, steroids, anti-IL6; mRNA vaccine available.

What type of virus is RSV?

ssRNA (–), enveloped; fusion proteins on surface.

What diseases are caused by RSV?

Bronchiolitis and pneumonia in infants; otitis media in children.

What type of virus is Parainfluenza?

ssRNA (–), enveloped.

What disease does Parainfluenza cause?

Croup, pneumonia in children; mild disease in adults.

What type of virus is West Nile virus?

ssRNA (+); mosquito-borne (bird reservoir).

What disease is caused by West Nile?

Fever, headache, confusion, encephalitis; diagnosed by titer or PCR.

What type of virus is Dengue virus?

ssRNA (+); Aedes aegypti mosquito vector.

What diseases are caused by Dengue?

Classic: retroorbital pain, fever; Hemorrhagic: thrombocytopenia, shock.

What type of virus is Yellow Fever virus?

ssRNA (+); Aedes mosquito.

What disease is caused by Yellow Fever?

Photophobia, myalgias, bleeding; vaccine available.

What type of virus is Zika virus?

ssRNA (+); Aedes mosquito, vertical, sexual.

What disease is caused by Zika?

Rash, joint pain, microcephaly in fetus.

What type of virus is Ebola?

ssRNA (–), enveloped.

How is Ebola transmitted and diagnosed?

Body fluids; diagnosed by PCR.

What disease is caused by Ebola?

Hemorrhagic fever, GI bleeding, DIC; supportive care only.

What type of virus is Measles virus?

ssRNA (–), enveloped.

What are symptoms of Measles?

Koplik spots, facial rash, encephalitis; MMR vaccine available.

What type of virus is Mumps virus?

ssRNA (–), enveloped.

What disease is caused by Mumps?

Fever, salivary gland swelling; MMR vaccine.

What type of virus is Rubella virus?

ssRNA (+), enveloped.

What disease is caused by Rubella?

Congenital rubella syndrome: cataracts, PDA, rash; MMR vaccine.

What type of virus is HIV?

Retrovirus, ssRNA (+), enveloped.

How does HIV replicate and spread?

Binds CD4 and CCR5; uses reverse transcriptase and integrase to integrate into host DNA.

What diseases are caused by HIV?

Acute: mono-like illness; Latent: asymptomatic; AIDS: PCP pneumonia, Kaposi sarcoma.

What is Parvovirus B19?

ssDNA, non-enveloped.

What diseases are caused by Parvovirus B19?

Erythema infectiosum (slapped cheek), aplastic anemia, hydrops fetalis.

What type of virus is Rabies?

ssRNA (–), enveloped.

How is Rabies transmitted and treated?

Animal bite; immune globulin and killed vaccine.

What disease does Rabies cause?

Furious: encephalitis, hydrophobia; Dumb: paralysis; both fatal.