Infection, Sepsis and Vaccines

Question 1

What causes infectious disease?

Answer 1

pathogens

Question 1

Describe virus replication

Answer 1

viruses cannot replicate independently and rely on host for most functions

Question 2

Describe pathogens and differentiate between primary and oppurtunistic

Answer 2

pathogens are infectious agents that cause disease to host
primary: capable of causing overt disease in healthy host
opportunistic: primarily cause disease in immunocompromised hosts

Question 3

List the 3 types of pathogenic organisms

Answer 3

prokaryotes, eukaryotes and viruses

Question 4

describe body response to low and high level bacterial infections

Answer 4

low level: local tissue phagocytes eliminate bacteria with innate non-specific defence
high level: induce adaptive specific immune response via antibodies

Question 5

How do viruses evade immune response?

Answer 5

they contain proteins that shut down immune system function

Question 6

List the most common causes of sepsis

Answer 6

bacterial, viral, fungal infections and non-infectious insults eg traumatic injury

Question 7

define sepsis

Answer 7

dysregulated systemic inflammatory and immune response to microbial invasion that produces organ injury

Question 8

describe the 3 stages of sepsis

Answer 8

stage 1: systemic inflammatory response denoted by high/low temp, tachycardia/pnoea, high/low WBC, known suspected infection
stage 2: severe sepsis diagnosed when acute organ dysfunction begins or when sepsis present along with HOTN or hypoperfusion
stage 3: septic shock where multiple organ failure occurs, defined by prescence of HOTN despite fluid resus, perfusion abnormalities leading to enhanced tissue damage

Question 9

what are symptoms of organ dysfunction?

Answer 9

decreased urine output, sudden changes in mental state, decreased platelet count, difficulty breathing, abnormal heart pumping function, abdo pain

Question 10

Compare active and passive immunisation

Answer 10

active: live attenuated pathogens in immunisation, induces immune response
passive: direct transfer of antibodies, temporary protection

Question 11

what does a vaccine contain?

Answer 11

antigen + adjuvant

Question 12

describe the function of adjuvant

Answer 12

activates inflam response, enhances immune response to antigen

Question 13

List the two main types of antibodies

Answer 13

IgM: first response Ab
IgG: major serum Ab

Question 14

Describe Ab function in Humoral immunity

Answer 14

extracellular pathogens are recognised by free antibodies in the bodies humours, antibodies bind to target and flag for destruction, bind to toxin and neutralise, specific