8. FLU

Question 1

What is FLU?

Answer 1

RnA virus, 8 sgmetn genome.
Has three main groups
A, B and C
All infect humans but A also infects birds

Question 2

What are the jobs of surface proteins on the flu?

Answer 2

Facilitates viral attachment and entry to the host cell- haemagglutinin

Neuraminidase- enables virion to be released from the host cell

Question 3

What is meant by antigenic drift when talking about the flu?

Answer 3

genetic variation within the virus that changes the properties of the antigen and means the immune system wont combat the virus as well. This causes worse epidemics and vaccine mismatch

Question 4

What is the difference between seasonal flu and pandemic flu?

Answer 4

Seasonal- occurs every winter. Affects 10-15% of the population. Usually unpleasant but not life threatening

Pandemic- occurs sporadically, affects 25% or more of the population, more serious, more complications

Question 5

What are the clinical features of FLU?

Answer 5

Abrupt fever (38-40)
Cough, sore throat, runny nose, myalgia, headache, malaise
systemic symptoms
less common N+V, diarrhoea

Question 6

What groups are at higher risks of contracting FLU?

Answer 6

Neurological, hepatic, renal, pulmonary and chronic cardiac disease
Diabetes
Immunosuppresion
Age over 65
Pregnancy
Children under 6
Morbid obesity

Question 7

What are some common complications of flu?

Answer 7

Acute bronchitis
Secondary bacterial pneumonia (20%)
Appears 4-5 days after the start of the flu
Typically caused by staph aureus, s.pneumoniae

Question 8

What are some less common complications of flu?

Answer 8

Resp- primary viral pneumonia, rpaid respiratory failure, mortality >40%

cardio- myocarditis, pericarditis

CNS- transverse myelitis, Guillain-Barre
Myositis and myoglobinuria

Question 9

How do you investogat e flu?

Answer 9

Viral nose and throat swabs-PCR
CXR
Blood culture
Pulse oximetry (<92 needs ABG and oxygen)
RR
U&E, FBC, CRP (should have in 4 days)

Question 10

What should be given straight away and within 48 hours of symptom onset?

Answer 10

Antiviral therpay!
Osetmivir- oral, 75mg every 12 hours for 5 days (firs line)

Zanamivir- inhaled or IV, 10mg inhaled up to 10 days

Question 11

What protection should healthcar staff take against flu?

Answer 11

Surgical face mask
Plastic apron
gloves
Vaccine!