URT Viruses

Question 0

Non-polio enterovirus

Answer 0

URT virus
-picornaviridae
-single-stranded, +sense linear RNA virus
-replicates in cytolplasm
-4 serotypes (A,B,C and D)
Pathogenesis
-virus infects and replicates in *oropharyngeal mucosa and lymphoid tissue
-passes to intestines to infect intestinal mucosa and *Peyer's patches
-disease manifestation due to virus-induced *cell lysis
Disease
-cold
-acute otitis media
-acute asthma attaks
-croup
-commonity-acquired pneumonia
Transmission
-direct contact w/ secretions
Diagnosis
-RT-PCR using CSF or throat swab

Question 1

Rhinovirus

Answer 1

URT virus
-picornaviridae
-single-stranded, +sense linear RNA virus
-replicates in cytoplasm
-3 groups (HRV-A, HRV-B & HRV-C), >200 serotypes
Replication
-"major" receptor=*ICAM-1
-"minor" receptor=*low-density lipoprotein receptor (LDLR)
-unknown receptor for *HRV-C
Disease
-cold
-acute otitis media
-rhinosinusitis
-croup
-bronchiolitis
-community-acquired pneumonia
-COPD
-asthma
Transmission
-kids!
-respiratory secretions

Question 2

Coronavirus

Answer 2

URT virus
-single-stranded, +sense, linear RNA virus
-helical, enveloped
-has crown-like projections
-replicates in cytoplasm
-winter
-6 serotypes that infect ppl:
  -229E, NL63, OC43, HKU1, SARS-CoV, MERS-CoV
Replication
-cytoplasmic, *error-prone replication
Transmission
-ppl contact
-respiratory droplets
-fomites
Symptoms
-flu-like
-SOB
-abnormal chest xray
-acute respiratory distress
-respiratory failure/death

Question 3

Adenovirus

Answer 3

URT virus
-icosahedral, naked
-double-stranded, linear DNA genome w/ viral protein attached to 5' ends
-replicates in nucleus
-12 spikes of *hemagglutinin, used for attachment
Replication
-infects mucosal epithelium of *resp. tract, conjunctivas and gastrointestinal tract
-latent in *adenoids, tonsils, or intestines
Common source of infection
-kids
-pools/ponds
-contaminated optometry equiment
-military recruits
Transmission
-fecal-oral
-respiratory secretions
-saliva
-fomites
-direct inoculation of conjunctivitis
Disease
-Infants (pharyngitis, coryza, otitis meida, pneumonia)
-children (upper respiratory disease, pneumonia, pharyngoconjunctival fever)
-adults (acute respiratory disease)
-immunocompromised (pneumonia)
Treatment
-self-limited and treatment is supportive
-cidofovir
Prevention
-adenovirus vaccine (for military only)
Diagnostic
-viral culture
-enzyme immunoassay or immunofluorescence assay
-PCR assays

Question 4

Herpes simlple virus 1

Answer 4

URT virus
-icosahedral, enveloped, spherical to pleomorphic
-double-stranded, linear DNA virus
-replicates in nucleus
Replication
-remains latent in *trigeminal ganglia
Disease
-keratoconjunctivitis
-gingivostomatitis - in kids
-tonsilitis
-labialis
-pharyngitis - adults
-esophagitis
-tracheobronchitis
Transmission
-oral-oral
-oral-genital
Treatment
-acyclovir
Prevention
-no vaccine
-safe sex
-gloves
-c-section
Diagnostic
-*cowdry type A inclusions
-*tzanck smear
-cell culture
-enzyme immunoassays
-immunofluorescence staining
-PCR

Question 5

Epstein barr virus

Answer 5

URT virus
-icosahedral, enveloped
-double-stranded linear DNA virus
-replicates in nucleus
-ubiquitous
-lifelong infection
-only 1 serotype
Antigens
-*VCA-viral capsid antigen
-*EBNA-nuclear antigen
Replication
-infects oropharynx, then B cells in blood causing heterophile atbs
-remains latent in *B cells
Disease
-"kissing dease"
-associated w/ burkitt's lymphoma, B-cell lymphomas, and nasopharyngea carcinoma
-causes oral hairy leukoplakia in HIV pts
-infectious mononucleosis (IM)
Treatment
-supportive therapy
Prevention
-no vaccine
Diagnosis
-atypical T cells (downey cell)
-lymphocytosis
-heterophile antibody

Question 6

Cytomegalovirus

Answer 6

URT virus
-icosahedral, enveloped
-large double-stranded, linear DNA virus
-replicates in nucleus
-*owl eyes
Transmission
-contact w/ infected *body fluids (urine, salive, breast milk, vaginal secretions, semen)
-oral, sexual and vertical transmission as well as by organ transplantations and blood transfusions
Disease
-adult (Infectious Mononucleosis)(milder than EBV)
-neonate of seronegative mother (cytomegalic inclusion disease)
-immunocompromised (multi-site symptomatic disease)
Prevention
-no vaccine
Diagnosis
-PCR, antigen detection, viral culture via shell vials, serology, or histology