Episcopal Diocese of Southern Philippines
BRENT HOSPITAL AND COLLEGES INCORPORATED
JUSTICE RT LIM BOULEVARD, ZAMBOANGA CITY
College of Nursing
MICROBIOLOGY AND PARASITOLOGY
EXERCISE 5
MICROBIAL CONTROL and INFECTION AND HOST RESISTANT
NAME: MADJALES, SUMAYYA B.
BSN 1-G
1. Differentiate bacteriostatic agent from a bactericidal one.
o Bacteriostatic means the agent prevent the growth of bacteria and
o Bactericidal means that it kill bacteria.
2. What are the factors that influence the action of chemical agents on bacteria?
o There are several factors that determine the antimicrobial activity of a disinfectant such
as the concentration of the agent, the temperature at which it is used, the time it is used,
the number and types of bacteria present, and the nature of the microorganism-carrying
material.
3.
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Enumerate the characteristics of a good disinfectant.
Broad-spectrum effectiveness
Active and stable
Safe for people and animals
Leaves No damage or Odor.
Environmental safe.
4.
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Enumerate the characteristics of a good antiseptic.
Biofilm penetration
long substantivity
tissue biocompatibility, and
Low resistance.
5. Differentiate antimicrobial agent from an antibiotic.
o Antibiotics are antibiotics that are used to treat infections caused by bacteria.
Antimicrobials, on the other hand, are a broader category of products that work against
bacteria in general.
6. Why do some microorganisms develop resistance to certain antibiotics?
o When bacteria evolve in a way that diminishes or eliminates the effectiveness of
antibiotics, chemicals, or other agents used to treat or prevent infections, antibiotic
resistance develops. Bacteria survive and reproduce, causing even more harm.
7.
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What are the three elements required to spread an infection?
Source or reservoir of infections agents
Susceptible host with a portal of entry receptive or the agent
Mode of transmission for the agent
8. Differentiate endogenous infection and exogenous infection.
o Endogenous-infection or disease originates with the body.
o Exogenous-infection or disease originates outside the body
9. Direct contact is one form of horizontal transmission of infection. Explain the meaning of
direct contact and cite specific examples.
o Direct contact infections spread when disease-causing microorganisms pass from the
infected person to the healthy person via direct physical contact with blood or body fluids.
o Examples of direct contact are touching, kissing, sexual contact, contact with oral
secretions, or contact with body lesions.
10. What are the different ways of preventing transmission of infection by direct contact?
o Wash and dry your hands regularly and well.
o Stay at home if you are sick.
o Cover coughs and sneezes.
o Clean surfaces regularly.
o Ventilate your home.
11. Aside from direct contact, name other modes of transmission of infection.
o Direct. Droplet spread.
Indirect. Airborne. Vehicleborne. Vectorborne
12. What are the main differences in disease-causation between bacteria, viruses, fungi and
parasites?
o Virus is a pathogenic microscopic organism.
o Viruses cannot multiply on their own, so they have to invade a ‘host’ cell.
o Pathogenic fungi are yeasts and moulds which can infect humans.
o Parasites are organisms that live on other organisms.
13. With your knowledge about microbial disease-causation, which of the four types of
microorganisms do you think is the most pathogenic?
o Bacteria because, some bacteria are well equipped to evade the body’s defense
mechanisms, and some produce toxins that cause symptoms and disease.
14. Draw the chain of infection and discuss.
o