Influenza

Question 1

3 factors of a seasonal flu (epidemic)…

Answer 1

occurs every winter, effects 10-15% of the population (localised), not lifethreatening. ASSOCIATED WITH IFB

Question 2

4 factors of a pandemic flu…

Answer 2

occurs sporadically, effects 25% (widespread), serious. ASSOCIATED WITH IFA

Question 3

what are the requirements for a pandemic?

Answer 3

human pathogenicity, new virus (shift) resulting in a susceptible populaiton, efficient person-person transmission.

Question 4

how may the infection be transmitted?

Answer 4

blood bourne, transplacental, faeco-oral, airbourne, droplet spread, direct contact

Question 5

incubation period?

Answer 5

2-4 days

Question 6

Clinical features?

Answer 6

Fever, dry cough, sore throat, severe headache, aches and pains, shivering, rhinitis, myalgia.

Question 7

Influenza like illness (ILI) 3 defining factors…

Answer 7

fever >38 AND cough, onset within last 10 days.

Question 8

what groups of people should be offered a yearly flu jab?

Answer 8

> 65yo, healthcare workers, people under 65 with chronic condiitions (DM, chd, lung disease, renal failure, immunosupressed, pregnant women, children under 6 months old, mobidly obese.

Question 9

common complications…

Answer 9

bronchitis, pneumonia,

Question 10

ix

Answer 10

nose, throat swabs, CXR, blood cultures, pulse oximetry, RR, u and e’s, fbc, crp

Question 11

what Is the antiviral therapy used?

Answer 11

OSELTAMIVIR (TAMIFLU) - oral, ZANAMIVIR (RELENZA) – Inhaled & or I.V., Peramivir

Question 12

how can healthcare staff protect themselves?

Answer 12

surgical masks, aprons, gloves, hand hygiene/washing

Question 13

what do vaccines consist of?

Answer 13

Chemically inactivated and purified, trivalent vaccines - Containing 2 type A & 1 type B subtype viruses, single 0.5ml IM injection.

Question 14

describe the Influenza virus, what is a b and c?

Answer 14

RNA, a,b and c, a infects mammals and birds, b and c infect humans. Surface proteins H and N, 18 different H antigens (H1-3 in humans), 11 different N antigens

Question 15

how does antigenic DRIFT impact the virus?

Answer 15

changes the antigenic properties and eventually immune system wint be able to combat the virus. Little changes. EPIDEMIC

Question 16

how does antigenic SHIFT impact the virus?

Answer 16

Abrupt major change mayresult in new h/n combinations thus also allowing jump from one animal species to another. New subtypes formed. There is reassortment of the virus’ gene segments, this may lead to pandemics.