Reservoirs & Transmission

Question 1

What is required for a pathogen to survive and spread?

Answer 1

They must infect a host, reproduce, and ensure that its progeny is transmitted to another host.

Question 2

Define pathogen reservoirs, list animal, organic, and inorganic reservoirs.

Answer 2

It’s a site where a microorganism may survive and multiply as a source of infection. (E.g. animal reservoir-zoonosis from ticks, rabies, etc) (e.g. organic reservoirs-spore formers and polio virus) (e.g. inorganic reservoirs-nosomical from hospital gowns etc, community from chairs, doors, etc)

Question 3

List some transmission routes.

Answer 3

Airborne, droplets, fecal-oral, sexual transmission, direct contact, etc…

Question 4

Briefly outline the no social transmission pathway of c. Difficile.

Question 5

Define/outline zoonosis and give an example.

Answer 5

Zoonosis is defined as an infectious disease that’s transmitted from animal to human or vice verca. (E.g. Rickettsia - DRAW CYCLE)

Question 6

List bodily entry routes.

Answer 6

Mucus membranes; RTI(via inhalation), GI(ingestion), STI
Skin; via skin lesions.
Parenteral; needles, surgery, bites, etc…

Question 7

Where are mucus membranes present and how do they relate to infection.

Answer 7

RT; illnesses such as strep throat, flu, whooping cough etc transmit via inhalation, droplets, aerosols.
GI; contracted via conatmainetd consumables (e.g. salmonella, h. Pylori, vibrio, clostridium botulinum)
STI; any type of sexual contact and conjunctiva. Examples of pathogens include HIV, HPV, chlamydia trachomatis, etc…

Question 8

Explain horizontal and vertical transmission.

Answer 8

Horizontal;
Vertical;

Question 9

What is congenital TORCH screening?

Answer 9

TORCH screening is a group of blood tests done to screen for toxoplasmosis, encephalitis, rubella ,herpes, and cytomegalovirus.

Feral complications with these diseases may result in birth defects and abortion.

Question 10

Explain AMR and suggestions for its prevention.

Answer 10

Antimicrobial Resistance (AMR) occurs when bacteria, viruses, fungi and parasites change over time and no longer respond to medicines making infections harder to treat and increasing the risk of disease spread, severe illness and death.

AMR may be managed/prevented by:
Limiting antibiotic prescriptions for self-limiting or mild illness.
Prevention of infections via proper hygiene.
More medical research, etc…

Question 11

Define/explain HAI’s and draw the chain of infection. (Give examples of HAIs)

Answer 11

• Healthcare-associated infections (HAIs) areinfections people get while they are receiving health care for another condition. HAIs can happen in any healthcare facility, including hospitals, ambulatory surgical centres, end-stage renal disease facilities, and long-term care facilities.
  
  • It’s an infection which was neither represent nor incubating at the time of admission and also includes infections which only become apparent after discharge.
• Nosocomial Infection → there are 2 sources of this type of infection.
  
  • Endogenous; organisms which are harmless in one site can be pathogenic when transferred to another site (e.g. E. coli)
  • Exogenous; organisms transmitted from another source (e.g. nurse, doctor, other patients, etc…)

Question 12

How might HAI’s be prevented?

Answer 12

Hand hygiene;
Aspectic techniques;
Bodily fluids;
PPE;
Sharps;

Question 13

What is the importance of risk assessment and management?

Question 14

Give an example of a pathogens cycle of infection depending on their route of entry.

Answer 14

Not all pathogens may cause disease, this depends on the portal of entry(some pathogens have preferred routes).

• S. pneumonia; if inhaled can cause pneumonia, if ingested - no disease.
• S. typhi; if ingested can cause typhoid fever, if on skin - no disease.