CHAIN OF INFECTION

1. State six (6) essential factors in the chain of infection and give two (2) example for each factor.

Infectious Agent
An agent capable of producing infection.
Example: Bacteria, Virus, Fungus, Protozoa, Helminth 

Reservoirs

Is the breeding ground for bacteria/viruses.

Somewhere which contain proper nutrients and suitable environment.

Example: Humans, Animals, Environment, Formites

Portal Of Exit

Is the path by which a pathogen leaves its host.

Through respiratory tract (nose, mouth), intestinal tract (rectum), urinary tract, or blood and other body fluids. 

Example: saliva from the oral cavity,sneezing,coughing,faeces from the bowel,vomits, infected blood and wound.

 

Means Of Transmission

An organism transfers from one carrier to another by either direct transmission or indirect transmission.               1.Direct Transmission

• Person-to-person transmission of pathogens through touching, biting, kissing, or sexual intercourse. 
• Example: expelled from the body by coughing, sneezing or talking
• Organisms travel in droplets over less than 1 metre in distance and are inhaled by a susceptible host.

     2. Indirect Transmission

• The transfer of an infectious agent from a reservoir to a host by suspended air particles, inanimate objects (vehicles), or animate intermediaries (vectors). 
• Airborne transmission occurs when infectious agents are carried by dust or droplet nuclei suspended in air.
• Vehicles that may indirectly transmit an infectious agent include food, water, biologic products (blood), and fomites (inanimate objects such as handkerchiefs, bedding, or surgical scalpels).
• Vectors such as mosquitoes, fleas, and ticks may carry an infectious agent through purely mechanical means or may support growth or changes in the agent.

Portal Of Entry

Opening where an infectious disease enters the host’s body such as mucus membranes, open wounds, or tubes inserted in body cavities like urinary catheters or feeding tubes.

Example: needlestick injury, open wound, ulcers, sexual contact, inhalation

Susceptible Host

Person who is at risk for developing an infection from the disease.

Example: someone who had low immunity, old people, children

 









2. Explain ten (10) nursing interventions to break the chain of infections.

A. Change client linen every morning.

     R: To reduce the microorganism in client's room.

B. Appropriate handling and disposal of body secretions like vomitus, faeces, sputum, blood          and body fluids.

     R: To prevent the spread of infection/microorganism. 

C. Apply effective hand washing.

     R: So that nurses won't carry the microorganism to another client.

D. Cover your mouth and nose when coughing and sneezing.

     R: To stop the microorganism from spreading out to others.

E. Do exercise at least three times a week.

    R: To maintain the health of the body.

F. Eat a proper nutrition.

    R: To have a good immune system.

G. Wear gloves when cleaning the wounds.

     R: To prevent microorganism/body fluids from entering/touching the skin.

H. Throw away needles in the clinical waste bin after used.

     R: To prevent the needles cut others person.

I. Throw away the facial tissue once you used.

   R: To prevent the fluids that contain microorganism flow to another person by touching it.

J. Wear full PPE which is gloves, masks, gowns, and goggles when entering isolation room.

     R: To prevent the microorganism flows to use through airborn infection.

WEEK 2 DISCUSSION

D. Microbiology terminologies

1. Aerobes

Is an organism.

Its can survive and grow in environment that is free of oxygen.

2. Aerobic bacteria

Bacteria that require the presence of oxygen to live and grow

3. Anaerobic

Bacteria that can survive and grow without the presence of free oxygen in their immediate environment

4. Antigen

A substance that when introduced into the body stimulates the production of an antibody.

Antigens include toxins, bacteria, foreign blood cells, and the cells of transplanted organs.

5. Antibody

An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens.

6. Antiseptic

A substance that inhibits the growth and reproduction of disease-causing microorganisms.

7. Antibiotic

A substance, such as penicillin or streptomycin, produced by or derived from certain fungi, bacteria, and other organisms, that can destroy or inhibit the growth of other microorganisms.

Antibiotics are widely used in the prevention and treatment of infectious diseases.

8. Antibacterial agent

Drugs that destroy or inhibit the growth of bacteria in concentrations that are safe for the host and can be used as chemotherapeutic agents to prevent or treat bacterial infections.

9. Antimicrobial agent

A general term for drugs, chemicals, or other substances that either kill or slow the growth of microbes.

10. Antiviral agent

Drugs that can destroys viruses

11. Antifungal agent

Drug that selectively eliminates fungal pathogens from a host with minimal toxicity to the host.

12. Asepsis

Methods to preventing contact with microorganisms

13. Antitoxin

An antibody formed in response to and capable of neutralizing a specific toxin of biological origin.

14. Bacteremia

Bacteremia is an invasion of the bloodstream by bacteria.

15. Commensal

An organism participating in a symbiotic relationship in which one species derives some benefit while the other is unaffected.

16. Culture medium

A liquid or gelatinous substance containing nutrients in which microorganisms or tissues are cultivated for scientific purposes.

17. Culture

The propagation of microorganisms or of living tissue cells in media conducive to their growth.

18. Disinfection

The process of killing pathogenic organisms or rendering them inert.

19. Endogenous infection

An infection caused by an infectious agent that is already present in the body, but has previously been inapparent or dormant.

20. Fomite

An inanimate object that can transmit infectious organisms.

21. Immunity

The condition of being immune; the protection against infectious disease conferred either by the immune response generated by immunization or previous infection or by other nonimmunologic factors.

22. Immunization

A process or procedure that protects the body against an infectious disease.

A vaccination is a type of immunization.

23. Immunoglobulin (Ig)

 A protein of animal origin with known antibody activity, synthesized by lymphocytes and plasma cells and found in serum and in other body fluids and tissues; abbreviated Ig.

There are five distinct classes based on structural and antigenic properties: IgA, IgD, IgE, IgG, and IgM.

24. Nosocomial infection

An infection that can be acquired in a hospital.

25. Pathogen

An agent that causes disease, especially a living microorganism such as a bacterium, virus, or fungus.

26. Septicemia

The medical term for blood poisoning, in which bacteria have invaded the bloodstream and circulates throughout the body.

27. Susceptible host

Any organism that can be infected by pathogens.

28. Sterilization

The procedure of elimination or destruction of all living microorganisms.

29. Toxemia

The condition resulting from the spread of bacterial products (toxins) by the bloodstream.

30. Toxoids

Toxins that have been treated to destroy their toxic properties but retain their ability to induce antibody production, thus creating an active immunity.

31. Vaccine

 A suspension of attenuated or killed microorganisms (viruses, bacteria, or rickettsiae), or of antigenic proteins derived from them, administered for prevention, amelioration, or treatment of infectious diseases.

CONT' WEEK 1 DISCUSSION

C. History of Microbiology

1. Antonie van Leeuwenhoek (1632-1723)

Antonie van Leeuwenhoek was born in Delft , the Netherlands , on October 24 1632.

He was known as 'The Father of Microbiology'.

He is a scientist and he is the person to observe and describe single celled organisms , which he originally referred to as animalcules which we called as microorganisms by using handcrafted microscopes.

Besides that, Leeuwenhoek also record and observe muscle fiber, bacteria, sperm, blood flow in capillaries, blood cells and rotifers.

2. Edward Jenner (1759 – 1833)

Edward Jenner was an English country physician

he discovered a safe and efficient vaccination against small pox which ultimately led to the eradication of small pox

Jenner observed that dairy workers, exposed to occupational

cowpox infection were immune to small pox.

he proved that resistance to small pox can be induced by injecting cow pox material from disease pustules into man (in 1796).

the general term 'vaccine' is given in honour of Jenner’s cow pox vaccine, to various materials used to induce active immunity.

Jenner's work is widely regarded as the foundation of immunology

3. Louis Pasteur (1822 – 1895)

Louis Pasteur was born on December 27, 1822, Dole, France

he was a French chemist and microbiologist.

he was one of the most important founders of medical microbiology.

louis pasteur discovered that microorganisms cause fermentation and disease 

he also developed vaccines against anthrax and rabies.

Pasteur’s greatest discoveries resulted in what he termed, “The Germ Theory of Disease” and led to breakthroughs in the causes and preventions of disease, methods of preservation and sanitary production of food. 

His work became the foundation for the science of microbiology, and a cornerstone of modern medicine.

4. Joseph Lister (1827 – 1912)

Joseph Lister was born on April 5, 1827 in Upton, England.

he was known as 'father of modern surgery'

he had interests in the fields of botany and zoology.

he qualified as a doctor in 1850.

Joseph Lister also obtained a Bachelor of Arts degree at the University of London in 1847.

he introduced new principles of cleanliness.

joseph lister granted that a surgeon will guard a patient's safety by using aseptic bt patients died after the procedure from 'ward's fever'.

lister thn became a Professor of Surgery.

Joseph Lister came out with a disinfectant spray with carbolic acid by doing an experiment with using one of Pasteur's proposed techniques, that of exposing the wound to chemicals.

carbolic acid cn reduce the spread of germs n reduced the rate of infection.

5. Robert Koch (1843 – 1910)

Robert Koch was born on December 11 1843 in Clausthal, Germany.

he was the founder of modern bacteriology

he was also a German physician tat contributed so much to the field of microbiology and infectious diseases. 

he identified the bacterium that causes anthrax (Bacillus anthracis) in 1877.

He recognized both the actively dividing cells and the dormant cells (spores) and developed techniques for studying them outside the body.

robert koch had also developed a way to grow bacteria in pure culture with cooking thickener (agar) which created a firm surface so the bacteria could be spread very thinly over the surface.

6. Paul Ehrlich (1854 – 1915)

Paul Ehrlich was born on March 14, 1854, in Strehlen, Silesia.

he undergo experiments with cells and body tissue revealed the fundamental principles of the immune system and established the legitimacy of chemotherapy.

he discovered the structural formula of atoxyl, a chemical compound that had been shown to be able to treat sleeping sickness (Silesia) in 1906.

His discovery of a drug that cured syphilis saved many lives and demonstrated the potential of systematic drug research.

He coined the term "chemotherapy" and popularized the concept of a "magic bullet" ("Paul R. Ehrlich").

he found the first empirical observation of the blood-brain barrier and the development of the first antibiotic drug in modern medicine (Silesia).

paul ehrlich was the person who developed the first antibiotic drug in modern medicine.

7. Alexander Fleming (1881 – 1955)

Sir Alexander Fleming was born on August 6, 1881, in Lochfield

he was a Scottish microbiologist who discovered penicillin, the first antibiotic.

he discovered penicillin and its effect on gram-positive microorganisms by observing a mould which had accidentally grown in a Petri dish with a culture of bacteria had killed the germs around it.

however, the penicillin became a life-saver in the Second World War

WEEK 1 DISCUSSION

A. Definition : Microbiology
Microbiology is the science of microorganisms. Microbiology in relation to medicine is concerned mainly with the isolation and identification of the microorganisms that cause disease. Microbiology is the studied of microbes.


B. Classification of microbiology
1. Bacteria are single celled microbes. The cell structure is simpler than that of other organisms as there is no nucleus or membrane bound organelles. Instead their control centre containing the genetic information is contained in a single loop of DNA. Some bacteria have an extra circle of genetic material called a plasmid. The plasmid often contains genes that give the bacterium some advantage over other bacteria. For example it may contain a gene that makes the bacterium resistant to a certain antibiotic

Bacteria are classified into 5 groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters.

2. Viruses are the smallest of all the microbes. They are said to be so small that 500 million rhinoviruses (which cause the common cold) could fit on to the head of a pin. They are unique because they are only alive and able to multiply inside the cells of other living things. The cell they multiply in is called the host cell.

A virus is made up of a core of genetic material, either DNA or RNA, surrounded by a protective coat called a capsid which is made up of protein. Sometimes the capsid is surrounded by an additional spikey coat called the envelope. Viruses are capable of latching onto host cells and getting inside them.

3. Fungi can be single celled or very complex multicellular organisms. They are found in just about any habitat but most live on the land, mainly in soil or on plant material rather than in sea or fresh water. A group called the decomposers grow in the soil or on dead plant matter where they play an important role in the cycling of carbon and other elements. Some are parasites of plants causing diseases such as mildews, rusts, scabs or canker. In crops fungal diseases can lead to significant monetary loss for the farmer. A very small number of fungi cause diseases in animals. In humans these include skin diseases such as athletes’ foot, ringworm and thrush.

4. Protozoa are single celled organisms. They come in many different shapes and sizes ranging from an Amoeba which can change its shape to Paramecium with its fixed shape and complex structure. They live in a wide variety of moist habitats including fresh water, marine environments and the soil.

Some are parasitic, which means they live in other plants and animals including humans, where they cause disease.Plasmodium, for example, causes malaria. They are motile and can move by:

Cilia - tiny hair like structures that cover the outside of the microbe. They beat in a regular continuous pattern like flexible oars.

• Flagella - long thread-like structures that extend from the cell surface. The flagella move in a whip-like motion that produces waves that propel the microbe around.
• Amoeboid movement - the organism moves by sending out pseudopodia, temporary protrusions that fill with cytoplasm that flows from the body of the cell.
  
  
  
  
  
  
  
  
  
  
  5. Algae can exist as single cells, an example of which is Chlamydomonas, or joined together in chains like Spirogyra or made up of many cells, for instance Rhodymenia (red seaweed).