Concept of Isolation

  • A state of separation between a person or group.
  • Isolation refers to various measures taken to prevent contagious disease from being spread from a patient to other patients, health care workers and visitors, or from other to a particular patient.

Types of Isolation

  • Strict isolation.
  • Respiratory isolation.
  • Contact isolation.
  • Enteric isolation.
  • Protective isolation.
  • Body fluid isolation.

Strict isolation


Suspected Highly infection transmissible bacterial or virulent disease by direct or indirect contact and air born routes of transmission.


Private room

Gown, mask, gloves, hand washing

Double bagged techniques for soiled articles.

Respiratory isolation

  • The indication is droplet transmission. Respiratory isolation is used for diseases that are spread through particles that are exhaled. Those having contact with or exposure to such a patient are required to wear a mask.
  • Requirements:

Private room

Gown, mask, gloves, hand washing

Patients with the same organism generally may share a room.

Labeled plastic bags are used for soiled articles.

Contact isolation


Infectious disease or multiple resistant microorganism that are spread by close or direct contact. Contact Precautions—used for infections, diseases, or germs that are spread by touching the patient or items in the room (examples: diarrheal illnesses, open wounds).


Private room

Gown, mask, gloves, hand washing.

Enteric isolation/enteric precaution


Infectious disease transmitted through

direct or indirect contact with infected feces.


A private room is required if the patient does not practice good hygiene measures.

Hand washing, gloves.

Gowns should only be worn when handling objects contaminated with feces.

Blood & body fluid precaution

  • Blood
  • Body fluid, blood semen, vaginal secretions, CSF, synovial fluid, pericardial fluid, peritoneal fluid, plural fluid, amniotic fluid, and tissues.


-Gloves, Mask, and protective eyes gear/cover.


-Contaminated needles should not be recapped.

-Use puncture resistant containers for used needles and other sharp items.

Relate isolation to the chain of infection Cycle

Source: – patient, employee, Environment, Equipment, visitors.

Method of transmission: –

Air tune, vehicle, vector,

Contact: (direct, indirect).

Host: – Age, immunity, treatment, nutrition, disease, lifestyle, skin injury, socioeconomics condition.

Identify nursing responsibilities in each type of isolation

1.Aseptic techniques

Always use aseptic technique any procedure in hospital

2. Isolation techniques-

Always use aseptic technique for the patient with communicable diseases (use of glove cap, Mask.

3. Fumigation-

Room and articles should be fumigation after death or discharge of patient with infectious disease or should be fumigated after specific interval.

4. Biological waste:

ward’s waste should be discarded in a proper way as per instruction.

5. Destruction of rodent and insects:

Rodent and insects also play a role in the spread of infection. They should be destroyed to prevent infection.

6. Hospital hygiene

The hospital should be well ventilated. The general cleanliness of the hospital maintained sweeping and mopping of the floor should be done, white washing of the walls windows, roofs, doors, should be done.

And other:

Droplet Isolation Precautions

  • Wear A Mask. …
  • Wear Goggles. …
  • Remove PPE and Perform Hand Washing After Completing Care and Leaving the Room. …
  • The Patient Should Be in a Negative-Pressure Room. …
  • Wear an Appropriate Respirator. …
  • Dispose of PPE in the Adjunct Room, Not Another Patient’s Room.

Concept of Asepsis


  • ASEPSIS: Asepsis is the state of being free from disease causing microorganisms such as bacteria, viruses, pathogenic fungi, and parasites.
  • Aseptic technique: It is a standard health care practice that helps to prevent the transfer of germs to or from an open wound and other susceptible areas on a patient’s body.
  • A technique used the practice and procedure to prevent contamination from pathogens.

Purpose: a septic technique helps to prevent health care associated infection.

  • Using aseptic techniques prevents the spread of infection by harmful germs.
  • Disinfecting a patient’s skin using antiseptic wipes.
  • Sterilizing equipment and instruments before a procedure.
  • Keeping sterilizing instrument inside plastic wrappers to prevent contamination before use.


Description automatically generated

Types of Aseptic Technique

  • There two types of techniques
  • Medical asepsis (“clean technique”): practices that kill some microorganisms to prevent them from spreading.
  • Surgical asepsis (“sterile technique”): practices that completely kill and eliminate microorganisms.

Medical or clean asepsis reduces the number of organisms and prevents their spread; surgical or sterile asepsis includes procedures to eliminate microorganisms from an area and is practiced by surgical technologists and nurses.


The spread of an infection within a community is described as a “chain,” several interconnected steps that describe how a pathogen moves about. Infection control and contact tracing are meant to break the chain, preventing a pathogen from spreading.

The transmission of infection depends on six elements which link together like chains.

The Spread of infection can be described as a chain with six components.

2. Understanding the Chain of Infection | ATrain Education

  1. Infection agent (Pathogen)
  2. Reservoir (the normal location of pathogens)
  3. Portal of exit from the reservoir
  4. Mode of transmission
  5. Portal of entry into a host
  6. Susceptible host

If any link is broken the chain is broken and infection cannot be transmitted.

1. The Infection Agent

(Pathogens) include not only bacteria but also viruses, fungi, and parasites. The virulence of these pathogens depends on their number, their potency, their ability to enter and survive in the body, and the susceptibility of the host. For example, the smallpox virus is particularly virulent, infecting almost all people exposed. In contrast, tuberculosis bacillus infects only a small number of people, usually people with weakened immune function, or those who are undernourished and living in crowded conditions.

Any disease-causing microorganisms (bacteria, virus, fungi, parasites etc).

2. The Reservoir

reservoir is any person, animal, arthropod, plant, soil or substance (or combination of these) in which an infectious agent normally lives and multiplies. The infectious agent depends on the reservoir for survival, where it can reproduce itself in such manner that it can be transmitted to a susceptible host.

Where the germs normally live e.g. person, water, food, animal, plant, soil or substance feces, intravenous fluid, and equipment in which an infectious agent normally lives and multiplies.

3. The Portal of exist

A portal of exit is the means by which a pathogen exits from a reservoir. For a human reservoir, the portal of exit can include blood, respiratory secretions, and anything exiting from the gastrointestinal or urinary tracts.

Route by which the infectious micro-organism escapes or leaves the reservoir,

  • Excretions
  • Secretions
  • Skin
  • Droplet flue cold 🡪 mucous secretions

4. The Mode of transmission (Spread) route

People release respiratory fluids during exhalation (e.g., quiet breathing, speaking, singing, exercise, coughing, sneezing) in the form of droplets across a spectrum of sizes. These droplets carry viruses and transmit infection. The largest droplets settle out of the air rapidly, within seconds to minutes.

The way of the pathogen gets from the reservoir to the new host. For example: –
Route of transmission from respiratory tract (Nose, Mouth)
Secretion of infected person, Example: – Cough and sneezing.

Droplet transmission
Agent is coughed or sneezed out into the air
and floats on droplets.

Diagram of Airborne Transmission

Direct spread by droplets:-

  • Close contact with infected person (<3ft)
  • Infected person coughs, sneezes, talks, sings,
  • Droplets land directly on mucous membranes.
  • (Eyes, Nose, Mouth) of susceptible person

Indirect spread by droplets: –

Someone touches contaminated object.

🡪Inhalation (e.g. Respiratory tract)

🡪Ingestion (e.g. GI tract)

🡪Absorption (e.g. mucous membranes of eyes)

🡪Break in skin (e.g. Needle stick, Cut).

🡪Interaction by medical procedure (catheter).

5. The Portal of Entry

Infectious agents get into the body through various portals of entry, including the mucous membranes, non-intact skin, and the respiratory, gastrointestinal, and genitourinary tracts. Pathogens often enter the body of the host through the same route they exited the reservoir, e.g., airborne pathogens from one person’s sneeze can enter through the nose of another person.

The route through which the pathogen enters its new host

  • Inhale germs
  • Sexual contact
  • Breaks in protective skin barrier
  • Ingestion

The Susceptible host

The final link in the chain of infection is a susceptible host, someone at risk of infection. Infection does not occur automatically when the pathogen enters the body of a person whose immune system is functioning normally. When a virulent pathogen enters an immune-compromised person, however, infection generally follows

A person who can get sick when exposed to a disease-causing pathogen.

  • Children who are very young.
  • People are on inadequate diets.
  • People who are chronically ill
  • People receiving medical therapy such as chemotherapy or high clothes.
  • People who are already ill.
  • People who open wounds.
  • If the chain is not broken the infectious organism is able to go on to develop disease in another person.

How to break the chain of infection?

  • Hand sanitizing and hand hygiene.
  • Cough and sneeze etiquette.
  • Proper use of personal protective equipment.
  • Sharp management.
  • Appropriate disposal of waste

Ways that infection may occur.

Three things are necessary for an infection to occur: Source: Places where infectious agents (germs) live (e.g., sinks, surfaces, human skin) Susceptible Person with a way for germs to enter the body. Transmission: Way germs are moved to the susceptible person.

  • Infectious disease can spread in a variety of ways.
  • Through air, from direct or indirect contact
    with another person, Soiled objects, skin or mucous membrane, saliva, urine, blood, and body secretions through sexual contact and through contamination of food and water.

Factors that increase the risk of infection: –

  • Diminished immune response.
  • Advanced age.
  • Malnutrition.
  • The presence of multiple chronic diseases.
  • Cognitive deficits, basic sanitary practices

(Hand washing).

  • Functional impairment such as incontinence or immobility.
  • Use of invasive devices like Catheters, ventilators, feeding tube.
  • Diminished ability to complain of or self-identify symptoms, or increased likelihood of presenting with atypical symptoms or signs of infection.


  • Example of common cold.
  • Any infection follows the same steps as that of chain of infection starting from infectious agent to susceptible host.
  • A flu virus deposited into the front of the nasal passages by contaminated fingers or by droplets from cough and sneezes.
  • Small dose of virus(1-30 particles)are sufficient to produce infection.

Role of health care personnel in infection control

Introduction to patient safety

  • Definition: patient safety is a discipline in the health care sector that applies safety science methods toward the goal of achieving a trust worthy system of health care delivery.
  • Patient safety is also an attribute of health care system ,it minimize the incidence and impact of adverse events and maximizes recovery from health problems.

Health care associated infection (HAI)

According to who:

  • HIA is also called nosocomial infection.
  • HIA is defined as:

An infection acquired in hospital by a patient who admitted for a reason other than that infection.

An infection occurs in a patient in a hospital or other health care facility in whom the infection was not present or incubating at the time of admission.

Impacts of Nosocomial infection (HIA)

  • Increase patients suffering.
  • Lead to permanent disability.
  • Lead to death.
  • Prolonged hospital stays.
  • Increase need of higher level of care.
  • Increase the costs to patients and hospitals.

Prevent from infections

Requires health care provider who have to,

– Knowledge of common infections and their vectors.

– An attitude of cooperation and commitment.

– Skills necessary to provide safe care.

-use universal precautions.

– Knowledge about the extent of the problem.

– Knowledge of main causes, modes of transmission and types of infection.

Universal precautions

Definition: universal precautions are a set of precautions designed to prevent transmission of HBV, HCV, HIV and other blood –borne pathogens while providing healthcare to all patients regardless of their diagnosis or presumed infection status.

Standard precautions:

Are the precautions to be used by all health care workers in all situations involving the care of patient of contact with the environment.

  • Hand hygiene
  • Gloves, apron/ gown, footwear.
  • Mask, eye protection and or face shield.
  • Preventing occupation Exposure.
  • Accommodation patient placement isolation.
  • Environment
  • Laundry
  • Blood and body fluid spillage
  • Clinical waste.

Nursing student needs

  • To apply universal precautions.
  • To be immunized against hepatitis B
  • To Use personal protection method
  • To know what to do if expose
  • They encourage others to use universal precautions.


Microbiology MCQs/BCQs

1. The media used for culturing salmonella is
a. VL-broth
b. Sabouruad agar
c. Slanetz bartley
d. Meat broth
e. Selenite Broth

2. Structural and functional as well as basic unit of life which was discovered by Robert hook.
a. Cell
b. Tissue
c. Organ
d. System
e. Human
3. Area of the cytoplasm that contains the single bacterial DNA molecule
a. Plasma
b. Nucleoid region
c. Cytoplasm
d. Ribosomes
e. Vacuole

4. Cells have “little organs” in it are collectively known as
a. Cell parts
b. Inter cell
c. Cell organelles
d. Cytoplasm
e. Golgi bodies

5. It is called the power house of cell.
a. Golgi bodies
b. Plasma membrane
c. Mitochondria
d. Cell membrane
e. Food vacuole

6. The bodies ability to fight against pathogens is known as
a. Microbiology
b. Histology
c. Pathology
d. Immunity
e. Biology

7. A patient skin-tested with purified protein derivative (PPD) to determine previous exposure to Mycobacterium tuberculosis develops induration at the skin test site 48 hours later. Histologically, the reaction site would MOST probably show:
a. Neutrophils
b. Helper T cells and macrophages
c. B cells
d. Eosinophils
e. A cells

8. It is highly complex jelly like material in which other parts are embedded.
a. Apoptosis
b. Cytoplasm
c. Ribosomes
d. Endoplasmic reticulum
e. Nucleus

9. Part of microscope that is hollow cylindrical tube & support the ocular lens is named as
a. Objective
b. Lens
c. Eye piece
d. Body tube
e. Nose piece

10. It acts as a barrier to invasion.
a. Skin
b. Bones
c. Organs
d. Cell
e. Brain

11. According to mitosis cell division has
a. 10 phases
b. 4 phases
c. 2 phases
d. 5 phases
e. 6 phases

12. It is a chemical substance derivable from a mold or bacterium that kills microorganisms and cures infections.
a. Antibiotic
b. Antigen
c. Protein
d. Virus
e. Bacteria

13. A child stung by a bee experiences respiratory distress within minutes and lapses into unconsciousness. This reaction is probably mediated by:
a. IgM antibody
b. Sensitized T cells
c. IgE antibody
d. IgF antibody
e. Sensitized T cells

14. organism made up of one of single cell are known as
a. multi cellular
b. muti nucleoid
c. nucleus
d. unicellular
e. animal

15. It is a milky body fluid that contains a type of white blood cells.
a. Body
b. Cell
c. Lymph
d. Plasma
e. Membrane

16. An injection of a weakened form of the actual antigen that causes the disease is called
a. Injection
b. Syringe
c. Vaccine
d. Inmmune system
e. Lymphocytes

17. A patient with a central nervous system disorder is maintained on the drug methyldopa. Hemolytic anemia develops, which resolves shortly after the drug is withdrawn. This is MOST probably an example of:
a. Cell-mediated hypersensitivity
b. Immune-complex hypersensitivity
c. Atopic hypersensitivity
d. Cytotoxic hypersensitivity
e. Non hypersensitivity

18. Are chemical substance as protein, carbohydrates, lipids (fats) or nutic acid which stimulates specific immune response.
a. Antibiotic
b. Antigen
c. Protein
d. Virus
e. Bacteria

19. The 3rd phase of mitosis (cell division) is known as
a. Anaphase
b. Metaphase
c. Telophase
d. Prophase
e. Cytokinesis

20. A small dense(thick) body in nucleus that contain ribo nucleic acid is known as
a. Metacarpals
b. Meta tarsals
c. Nucleoli
d. Nucleus
e. Ribosomes

21. An immunoglobulin is a
a. Carbohydrate
b. Glycoprotein
c. Protein
d. Minerals
e. Amino acid

22. It is useful to stimulate antibody production
a. An adjuvant
b. A hapten
c. A protein
d. Red blood cells
e. Purified antigen

23. The resistance power of body against infectious agents like bacteria, virus etc.
a. Microbiology
b. Histology
c. Pathology
d. Immunity
e. Biology

24. In this type of cell division four haploid gametes are produced.
a. Mitosis
b. Meiosis
c. Decomposition
d. Photosynthesis
e. Sterilization

25. A part of microscope that is circular shutter which regulates the size of opening through which light processes in the condenser.
a. Condenser
b. Mirror
c. Arm
d. Diaphragm
e. Inclinations joint

26. A process of A-sexual reproduction or simple method of cell division that occurs in unicellular organisms.
a. Sterilization
b. Fertilization
c. Meiosis
d. Mitosis
e. Sanitization

27. The first person to identify microbes as causing disease was
a. Louis Pasteur
b. Robert Koch
c. Robert hook
d. Ivan lewin hook
e. Edward jenner
28. A minute animal or vegetable which can’t be seen by naked eye but just can be seen by micro-scope.
a. Macro organism
b. Micro organism
c. Human being
d. Ant
e. Elephant
29. A disease in which minute organisms, invisible to the naked eye, invade and multiply within the body.
a. Infectious disease
b. Healthy disease
c. Disease
d. Infection
e. Microscopic disease

30. Those diseases that are found normally in a population are named as
a. Epidemic
b. Endemic
c. Pendemic
d. Epizootic
e. Incidence


31. Respiratory acidosis and alkalosis are due to a problem with the
a. Heart
b. Lungs
c. Hands
d. Foot
e. Brain

32. Metabolic acidosis and alkalosis are due to a problem with the
a. Kidney
b. Pancreas
c. Gall bladder
d. Urinary bladder
e. Bones

33. The movement of molecules across the cell membrane and does not requires energy is known as
a. Passive transport
b. Active transport
c. Cellulose
d. Movement
e. Motion

34. A term for the language deficit accompanying cerebral stroke is
a. Agraphia
b. Anosognosia
c. Dysphagia
d. Aphasia
e. Euphoria

35. The inability to carry out a motor task on command given adequate strength, sensation, coordination and comprehension is called:
a. Aphasia
b. Apraxia
c. Alexia
d. Aprosodia
e. Abulia

36. A 64 year-old right handed male presents with right upper limb plegia, right lower limb paresis, a hemi sensory deficit, a decreased ability to comprehend verbal or written commands and poor language output. His lesion is most likely in the:
a. Basal ganglia
b. Middle cerebral artery distribution
c. Posterior cerebral artery distribution
d. Brain stem
e. Anterior cerebral artery distribution

37. A stroke affecting the back part of a brain could affect
a. Lungs
b. Heart
c. Sight
d. Taste
e. Smell

38. Hemorrhagic Stroke is associated with
a. Hypertension
b. Dialysis
c. Resting
d. Fatigue
e. Hepatitis

39. The carrier-mediated transport of large molecules through the cell membrane using transport proteins embedded within the cell membrane is known as
a. Passive transport
b. Active transport
c. Facilitated diffusion
d. Movement
e. Motion
40. A semi permeable membrane separating the blood from the cerebrospinal fluid, and constituting a barrier to the passage of cells, particles, and large molecules.
a. Permeable membrane
b. Cell membrane
c. Cell wall
d. Blood brain barrier
e. Kidney blood barrier


41. “The movement of solute molecules and water across a membrane by normal cardiovascular pressure” refers to
a. Permeability
b. Semi permeability
c. Filtration
d. Vibration
e. Movement

42. The sodium-potassium pump carries out a form of
a. Active transport
b. Passive transport
c. Sterilization
d. Filtration
e. Disinfection

43. The diffusion of a solute across a selectively permeable membrane. In this case the solute molecules always move from the stronger concentration (hypertonic) to the weaker (hypotonic).
a. Diffusion
b. Osmosis
c. Dialysis
d. Filtration
e. De colorization

44. The most important carbohydrate is
a. Fructose
b. Lactose
c. Glucose (monosaccharide)
d. Sucrose
e. Glycoprotein

45. Cholesterol is a type of
a. Protein
b. Carbohydrate
c. Amino acids
d. Lipids
e. Fats
46. Anti lipolytic hormone is
a. Insulin
b. Epinephrine
c. Nor epinephrine
d. Thyroid
e. Serotonin

47. The maintenance of steady levels of glucose in the body is known as
a. Lipid regulation
b. Fat regulation
c. Serotonin regulation
d. Gluco regulation
e. Thyroid regulation

48. The entire spectrum of chemical reactions, occurring in the living system is termed as
a. Metabolism
b. Anabolism
c. Catabolism
d. Ion regulation
e. Insulin regulation

49. Synthesis of glucose from non carbohydrate compounds is known as
a. Glycoprotein
b. Glycolipids
c. Glucose
d. Lactogenesis
e. Glycogenesis

50. Non essential amino acids are named as
a. Dispensable amino acids
b. Non dispensable amino acids
c. Regulatory amino acids
d. Retained amino acids
e. Fatty amino acids

Note: attempt any five questions. All questions carry equal marks
Qno1. Write a short note on blood brain barrier?
Qno2. Discuss briefly active and passive transport in general with examples and explain sodium potassium pump?
Qno3. Differentiate between trauma and cellular injury?
Qno4. Define microbiology and briefly discuss its importance in nursing?
Qno5. Define immunity and explain its types with at least two examples for each type?
Qno6 write short note any one of the following
a. Mitosis
b. meiosis
Qno7. Differentiate between unicellular and multi cellular organisms with examples and differentiate between eukaryotes and prokaryotes with examples?

Answer key
01 E
02 A
03 B
04 C
05 C
06 D
07 B
08 B
09 D
10 A
11 B
12 A
13 E
14 D
15 C
16 C
17 D
18 B
19 A
20 C
21 B
22 A
23 D
24 B
25 D


26 D
27 B
28 B
29 A
30 B
31 B
32 A
33 A
34 D
35 B
36 B
37 C
38 A
39 C
40 D
41 C
42 A
43 C
44 C
45 D
46 A
47 D
48 A
49 E
50 A