Cold, flu, COVID & MMR

Question 1

Transmission of viral infections

Answer 1

• Via droplets or contacts with nasal secretion/saliva

Question 2

Bodies non specific and immune defense:

Answer 2

• Respiratory endothelial cells (ECs) covered thick glycocalyx & tracheobronchial mucus (traps viral particles)
• Cilliated respiratory ECs move particles from lower to upper respiratory tract, then swallowed
• Lung immune response

Question 3

Name and describe four main respiratory viruses

Answer 3

Question 4

How to prevent viral respiratory infections

Answer 4

Good hygiene, hand-washing, tissues (sneezing)

Question 5

Common cold: cause (which type of virus), symptoms, mechanism and treatment

Answer 5

• CAUSE: Most by rhinoviruses and some coronaviruses
• SYM: Fever, sore throat, runny nose, sneezing, nasal congestion, headache
• MECHANISM: rhinovirus – binds receptors on ciliated surface of nasal epithelial cells (e.g. ICAM1) followed by receptor-mediated endocytosis. Leads to pro-inflammatory response
• TM: symptomatic: analgesia & antipyretics. Possible other OTC options

Question 6

What is SARS-CoV-2

Answer 6

• New type of coronavirus
• Caused COVID-19
• Enter cells via Angiotensin Converting Enzyme 2 (ACE2) on host cell
• ACE2 highly expressed in epithelium of lung + intestine, and lesser extent in other tissues e.g., liver & kidney

Question 7

SARS-CoV-2 Mechanism

Answer 7

• Virus enters host cell by 2 main mechanisms: early/cell surface or late/endocytosis
• S protein (S1, RBD) binds to ACE2
• Proteolytic cleavage between S1 and S2 by TMPRSS2 (when present) activates the S protein releasing S1 and allowing fusion via S2 and cell surface entry
• In absence of TMPRSS2, following binding to ACE2, virus enters via endocytosis
• Cleavage in S protein by Furin before exit can prime virus for entry to infect new cells
• Several stages of these pathways are possible therapeutic targets

Question 8

COVID 19: cause (which type of virus), symptoms, diagnosis and treatment

Answer 8

• CAUSE: SARS-CoV-2 virus
• SYM: Fever, cough, loss of smell and taste, fatigue, shortness of breath
• DIAGNOSIS: Lateral flow test
• TREATMENT: None, symptomatic management, vaccine for prevention. Corticosteroids (anti infl), monoclonal antibodies, anti viral drugs

Question 9

What is the influenza virus

Answer 9

• Three types: A, B and C
• A found in humans and animals, B/C only humans
• 2 different types surface protein: haemaglutinin (H) and neuraminidase (N)
• Influenza A is a threat, B less severe and C is uncommon

Question 10

Influenza: symptoms, treatment

Answer 10

• SYM:
• TM: AB may be prescribed for secondary bacterial infections, antivirals like zanamivir or oseltamivir for at risk patients. Otherwise symptomatic treatment only

Question 11

What is Varicella-Zoster Virus and shingles

Answer 11

• Herpes virus, primary infection causes chicken pox (varicella)
• Shingles is a rash and pain for 3-5 weeks. Usually on torso

Question 12

Varicella-Zoster Virus: Symptoms, complications, treatment

Answer 12

• SYM: Rash, red spots, fever
• COMP: Pneumonia, infections in lesions, encephalitis
• TM: Calamine lotion, paracetamol

Question 13

Shingle symptoms treatment

Answer 13

• SYM: Rash 3-5 weeks on torso mainly
• TM: Antiviral drugs and pain management. Aciclovir, famciclovir, valaciclovir

Question 14

MMR (measles, mumps, rubella) symptoms , tm

Answer 14

• Vaccinations
• No treatment