Week 7 - Fresher's Flu Flashcards
Name 5 viruses that infect the upper respiratory tract
Rhinovirus Coronavirus Influenza virus Parainfluenza virus Respiratory syncytial virus Herpesvirus Adenovirus Bocavirus Coxsackvirus
Name 5 viruses that infect the lower respiratory tract
Influenza virus Parainfluenza virus Respiratory syncytial virus Adenovirus Bocavirus Metapneumovirus
What are symptoms of a cold? How common are colds?
Sneezing
Rhinitis (blocked nose)
Cough/coryza
Sore throat
Common - multiple colds a year
What are the symptoms of the flu?
How frequent is the flu?
What is the onset?
Sudden onset (within hours)
Fever, chills, shivering
Headache
Myalgia (pain in certain muscle groups) - systemic, their whole body hurts
Cough
Rarely more than once per year, usually less frequent
Infectious from 24hrs pre symptoms to 5-7days after illness starts
Can sometimes have GI symptoms, vomitting and diarrhoea due to high temp
What is Fresher’s Flu?
Term used in UK
Affects students when they arrive at university
Usually doesn’t involve influenza
What are the potential causes of Fresher’s Flu?
- Upper Resp tract infection (exposure to novel viruses)
- Excess alcohol
- Lack of sleep
- Homesickness
- Adjustment to living independently
Usually doesn’t involve influenza
How do you diagnosis a cold?
Based on symptoms
Exclusion of more serious illness
Mild, self-limiting
Better within 7 days, usually feel better within 2/3 days
How do you diagnosis a flu?
Presence of fever and systemic symptoms
Prolonged illness 7-10 days
Rapid onset (within hours)
Contact with flu - travel or local outbreak
Lab diagnosis
Which animals does Influenza A affect?
- Humans
- Mammals
- Birds
Which animals does Influenza B affect?
Human
Seals
Which animals does Influenza C affect?
Human
Pigs
Dogs
Which animals does Influenza D affect?
Cattle
Pigs
How many cases of flu?
3 - 5 million cases a year
How many annual deaths are due to the flu?
250 000 - 750 000 deaths annually
Mostly in people over 65
Why is there a need for an annual vaccination?
The vaccine each year is based on predicted circulating strains
- Numerous flu viruses circulating at any given time
- Antigenic drift - minor changes in the antibody binding sites so the flu virus is not recognised by the immune system
- Antigenic shift - major changes with the circulating virus (combo with diff viruses - mix with avian/porcine with human virus) creating a new subtype of flu
- Potential for pandemic with antigenic shift
What to do if you think you have the flu?
- Rest
- Keep hydrated
- Keep warm
- Let people know
- Continue to take any prescribed medication (esp insulin)
- Self report
- Don’t take antibiotics - they don’t work on viruses
- Cover your mouth/nose when coughing
What are some red flags with the flu?
- Haemoptysis
- Persistent fever
- Confusion
- Non-blanching rash
- Persistently enlarged lymph nodes
- Lethargy
- Difficulty breathing
- Difficulty swallowing own saliva
What are 5 ways to avoid getting the flu?
- Get flu vaccine each year (even if you get the flu, the symptoms will be milder)
- Avoid being around people who have the flu
- Try not to touch your eyes, nose or mouth (germs enter the body easiest this way)
- Clean and distinct surfaces if you are sharing a home with someone with the flu
- Wash your hands regularly
Who are at greater risk of severe disease or complications when infected by the flu?
- Pregnant women
- Children under 59 months
- Elderly
- Individuals with chronic medical conditions (chronic cardiac, pulmonary, renal, metabolic, neurodevelopmental, liver, hematologic diseases)
- Individuals with immunosuppressive conditions (e.g. HIV/AIDs, people receiving chemotherapy or steroids, malignancy)
- Health care workers increased risk of getting the flu generally due to exposure
Name two viruses that commonly cause colds?
2 marks
Any two from: · Rhinovirus · Adenovirus · Coronavirus · Respiratory syncytial virus
List 3 symptoms of flu that distinguish it from a cold
3 marks
Any 3 from: · Fever >38ºC . Muscle aches · Rapid onset of symptoms (within hours) · Headache · Chest discomfort/cough
Name the two glycoproteins on the flu virus envelope that are the target for antiviral agents and vaccines
(1 marks)
Hemagglutinin (1/2 mark)
and
neuraminidase (1/2 mark)
Explain how osetltamivir (Tamiflu) works
2 marks
Oseltamivir is competitive inhibitor of an influenza’s neuraminidase enzyme (1/2 mark).
The enzyme cleaves the sialic acid which is found on glycoproteins (1/2 mark) on the surface of human cells that helps new virions to exit the cell (1/2 mark).
Oseltamivir prevents new viral particles from being released from an infected host cell (1/2mark).
Explain why flu vaccination needs to be administered annually.
(2 marks)
Multiple strains of flu can be in circulation (1/2),
Errors in virus replication mean that antigenic drift is continually producing variant viruses (1/2),
Previous infection or vaccination will not protect against new strains particularly if antigenic shift occurs (1)
Where are the different sites you can take someone’s temperature?
Oral
Rectal
Tympanic
Forehead
Which method of taking someone’s temperature is closest to the core temperature?
Tympanic and rectal
What is the range for having a high temperature for a baby or young child?
Above 38 degrees
What is the range for having a high temperature for a older child or adult?
37.2 - 37.5 degrees
For tympanic 35 degrees is high
What is tympanic temperature?
Reading someone’s temperature from their ear
Are upper resp tract or lower resp tract infections more serious?
Lower
How many URTIs do pre school children usually get in a year?
6-10 URTIs
Children aren’t very good at clearing their airways, they don’t cough properly and clear everything
Children will often present with constant runny noses when actually they are just getting infected from different viruses
What is part of the upper respiratory tract?
Nasal cavity
Pharynx
Larynx
What is part of the lower respiratory tract?
Trachea
Primary bronchi
Lungs
How many viruses can cause mild URTIs?
200+
Not pneumonia or bronchitis/chest infections
Which viruses specifically cause colds?
Main ones: Rhinovirus Coronavirus Adenovirus Respiratory Syncytial virus (can cause hospitalisation in young children)
Parainfluenza virus
Influenza B can be mild
What time of year is flu prevalent in the UK?
November - Feb/March
Winter months
What virus causes flu?
Influenza
What virus family is influenza a part of?
What are their properties?
Orthomyxovirus
Properties:
Single stranded RNA
Spherical or filamentous vision with numerous surface projections of glycoprotein