Key Viruses - Non-blood borne Flashcards
List the 5 key Non-blood borne Viruses?
- Adenovirus
- Herpes virus
- Norovirus
- Herpes zoster (varicella zoster)
- Dengue fever
Describe structure of Adenovirus?
- dsDNA linear
- Icosahedral
- Non-enveloped
- Viral fibres on surface
Transmission of Adenovirus?
- Respiratory route via inhalation of droplets
- Inoculation of eye by virus-infected hand
- Infected bodies of water
Mode of infection of Adenovirus?
- Attachment to host cell receptors by tips of viral fibres.
- entry by receptor-mediated endocytosis
- replication inside the cell
Virulence of adenovirus?
- Icosahedral capsid = protects viral Nucleic acid
- viral fibres = allow attachment to host cell
Conditions linked to adenovirus?
- Respiratory disease (acute resp. Disease, viral pneumonia) - ocular infections (conjunctivitis) - gastrointestinal infections (latent) - urinary tract infections
Investigations for Adenovirus?
- viral PCR & ELISA test = using stool sample
Treatments for Adenovirus?
- vaccine
Describe structure of norovirus?
- ssRNA
- Non-enveloped
- single capsid protein
- spherical shape
Transmission of Norovirus?
- Faecal-oral route
- person to person
- infected surfaces
- contaminated food and water
Virulence factors for Norovirus?
- capsid protein
Conditions commonly liked to Norovirus?
- Acute gastroenteritis
- winter vomiting bug
- nausea, Diarrhoea & vomiting
Investigations for norovirus?
PCR then…
- Radioimmunoassay
- ELISA
treatment for Norovirus?
Prevention =
- proper hand washing, PPE, aseptic technique, kitchen hygiene to prevent contamination of food.
Treatment = isolate/quarantine patient - immune system usually deals with it within 48 hrs. Therefore only supportive treatments — - fluid resus - maintenance of physiological integrity
Describe structure of Herpes simplex virus?
- dsDNA
- Icosahedral capsid
- enveloped
- tegument
Transmission of herpes simplex virus?
Sexually transmitted
Direct contact with —
- virus-containing secretions or lesions.
> on mucosal or cutaneous surfaces
Can pass by asymptomatic shedding
Mode of infection of herpes simplex virus?
- During cell growth, the genome of the virus is replicated along with the chromosomes of the host cell.
- Latent infection is that produced by herpes simplex virus type 1 (HSV-1) is a Latent infection.
- The result of reactivation of HSV-1 = cold sores, fever etc.
Virulence factors of Herpes simplex virus?
- icosahedral capsid
- envelope
- tegument = contains virus-encoded enzymes & transcription factors
Symptoms of herpes simplex virus?
Flu-like symptoms
- fever
- swollen lymph nodes
- headache
- fatigue
- appetite loss
- blistering sores (both)
- pain on urination (genital)
- itchiness
- eye pain & redness
Investigations for herpes simplex virus?
- characteristic patient examination
- viral PCR
Treatment for herpes simplex virus?
- Acyclovir
Describe shape of herpes zoster (varicella zoster)?
- dsDNA
- Tegument
- surface glycoproteins
- enveloped
Transmission of herpes zoster?
Person to person with —
- causal contact
- respiratory droplets
Varicella zoster mode of infection?
Incubation period (primary viremia)
- infection of upper resp. Mucosa by virus II gets droplets
- virus spreads to regional lymph nodes, where it replicates
- virus spreads to liver and spleen
Contagious period (secondary viremia)
- infection of skin leads to appearance of vesicular rash.
- also fever and other symptoms.
Latency
- virus enters cutaneous neurones and migrates to dorsal root ganglia where it enters a latent state
