Epidemiology of the infectious disease

Question 1

What is the definition of Epidemiology of infectious disease?

Answer 1

Epidemiology is the study of how often diseases occur in different groups of people and why. Epidemiological information is used to plan and evaluate strategies to prevent illness and as a guide to the management of patients in whom disease has already developed

Question 2

Robust pathogen

Answer 2

can survive without the host

Question 3

example of a robust pathogen;

Answer 3

Covid-19 ; can be transmitted via droplets

Question 4

fragile pathogen

Answer 4

can only survive when in the presence of the host

Question 5

3 major ways pathogens can be transmitted

Answer 5

1. Transmission between humans
2. Via environmental factors (such as soil or water)
3. Between humans and animals (via vectors)

Question 6

Human to human transmission

Answer 6

Aerosol
Transfer of these pathogens is via the respiratory system when one person breathes, coughs, or sneezes pathogens into the air which then enter the respiratory system of another person.

Question 7

Robust pathogens will remain infective for ______ periods in the air and their transmission is termed airborne. More fragile pathogens will only survive for _____ periods when encased in respiratory secretions and their transmission is termed droplet

Answer 7

long
short

Question 8

Direct contact

Answer 8

contact with skin, mucous membrane, blood or any other body fluids
Examples of infections that can be spread by direct contact include ringworm, chickenpox and cold sores.

Question 9

Indirect contact

Answer 9

The pathogen gains entry to the new host via some other surface (or the air).

Objects that can facilitate transmission of pathogens are termed fomites – e.g., used tissue, handrails, utensils, etc.

Question 10

Faecal-oral

Answer 10

When pathogens are excreted from the gut of an infected person and then enter the gut of a new host via their mouth (usually indirectly via contaminated food, water or other fomite).
E.g., cholera, hepatitis A, rotavirus and most intestinal worms

Question 11

Transmission of blood-borne pathogens

Answer 11

via unsafe injections, contaminated transfusions of blood or blood products, or needle-stick injuries

Question 12

Environmental transmission

Answer 12

soil
water - occurs when bacteria, bacterial spores (that can germinate in the gut) or toxins, viruses and protozoa survive and replicate within water without a human host.

Question 13

What is zoonoses?

Answer 13

infectious diseases where the pathogen is transmitted from an infected animal to a human (in these cases the animals are the reservoirs

Question 14

explain Vector-borne transmission

Answer 14

the life cycle of the pathogen takes places in the human host, however, part of the life cycle must take place in another species which is known as the vector.
E.g., malaria
Common vectors for infectious diseases include mosquitoes, flies, ticks and lice

Question 15

Prevention of malaria

Answer 15

• do not wear perfume
• wear long sleeves
• apply cream on arms

Question 16

Spectrum of Antibiotic activity

Answer 16

• measure how many different types of organisms the antimicrobial targets
• antimicrobial that targets a specific group of organisms, narrow spectrum
• targets wide range of organisms - broad spectrum
• applies to antibiotics and antifungals

Question 17

Broad spectrum antibiotics commonly refers to antibiotics that target both

Answer 17

gram positive and negative bacteria

Question 18

flower diagram

Answer 18

for spectrum of activity : side 28

Question 19

slide 30
Dicloxacillin
Flucloxacillin

Answer 19

active against gram positive but not gram negative

Question 20

slide 31; Amoxicillin/ clavulanate

Answer 20

active against gram positive and negative

used more thay dicloxacillin - active against gram positive and gram negative bacteria