Pathogenic Microorganisms (With Specimen)

Let us make an in-depth study of the pathogenic microorganisms. The below given article will help you to learn about the following things: 1. Pathogens transmitted from the Respira­tory tract 2. Pathogens transmitted from the Intesti­nal and/or Urinary tract 3. Pathogens transmitted from the Genital tract 4. Pathogens transmitted in the blood and 5. Pathogens from the Soil.

Unit A:

Pathogens transmitted from the Respira­tory tract.

Unit B:

Pathogens transmitted from the Intesti­nal and/or Urinary tract.

Unit C:

Pathogens transmitted from the Genital tract.

Unit D:

Pathogens transmitted in the blood.

Unit E:

Pathogens from the Soil.

Unit A: Pathogens Transmitted from the Respiratory Tract:

(A) Cocci:

(a) Staphylococci;

(b) Streptococci;

(c) Pneumococcus (Diplococcus pneumonia);

(d) Neisseria meningitidis.

(B) Bacilli:

(a) Corynebacterium diphtheriae;

(b) Mycobacterium tuberculosis and Myco leprae;

(c) Haemophilus influenzae;

(d) Moraxella lacunata;

(e) Bordetella pertussis.

(C) Spirochaete:

(a) Borrelia vincenti.

(D) Virus:

(a) Small poxvirus;

(b) Measles;

(c) German Measles

(d) Chicken pox;

(e) Herpes Zoster;

(f) Common cold virus;

(g) Influenza;

(h) Psittacosis virus;

(i) Mumps;

(j) Poliomyelitis virus;

(k) Rabies virus.

Unit B: Pathogens Transmitted from the Intestinal Tract/or Urinary Tract:

(A) Bacteria:

(a) Food borne microorganisms (Food infection and food poisoning);

(b) Salmonella;

(c) Shigella;

(d) Escherichia coll;

(e) Vibrio cholerae;

(f) Clostridium.

(B) Enteric Virus:

(a) Poliomyelitis;

(b) Coxsachie virus;

(c) ECHO virus;

(d) Hepatitis virus;

(e) Bacteriophage.

(C) Parasites:

(i) Protozoa

(a) Entameba histolytica;

(b) Giardia lamblia;

(c) Trichomonas hominis.

(ii) Helminths:

(a) Cestodes;

(b) Trematodes;

(c) Nematodes.

Unit C: Pathogens Transmitted from Genital Tract:

(a) Treponema pallidum;

(b) Gonococci;

(c) Lymphogranuloma venereum;

(d) Trichomonas vaginalis.

Unit D: Pathogens Transmitted in the Blood:

(a) Secondary and accidental infections;

(b) Arthropod-borne bacterial infections;

(c) Arthropod-borne rickettsial and viral infec­tions;

(d) Arthropod-borne protozoal and helmin­thic diseases.

Unit E: Pathogens from the Soil:

(a) Bacterial pathogens of the soil:

(i) Clostridium welchii;

(ii) Clostridium tetani;

(iii) Bacillusanthracis;

(iv) Fungi.

Bacteria of medical importance have already been classified according to their shape into three main groups:

Cocci (spheres); bacilli (rods); spirochaetes (curved or spiral).

Transmission of Respiratory Tract Infection:

Oral and nasal secretions contaminate the atmosphere with pathogenic micro organisms during talking, laughing, sneezing, coughing or by droplet nuclei. Similarly, eating utensils, drinking glasses are contaminated with the ubiquitous pathogens. Thus, we constantly encounter the atmosphere laden with formidable infectious agents. It is very difficult to re­duce the atmospheric microbial content as it is in constant continuous process. The health is in con­stant threat because of the atmospheric pollution.

Control of Respiratory Infections:

The nurse plays a vital role in controlling the spread of respiratory pathogens by her “check posts” in the path of respira­tory pathogens.

The following are the effective check posts:

(a) Thorough washing of hands known to be soiled with respiratory tract discharges;

(b) Adequate sanitization of dishes and eat­ing utensils;

(c) Disinfectant laundering of bedding of pa­tient with any infectious disease (i.e., hot water or soaking in disinfectant, hot iron­ing);

(d) Disinfection of blankets, mattresses by autoclaving or sporicidal vapour or gas;

(e) Use of clean handkerchief or tissue paper for sneezing and coughing;

(f) Use of proper sputum containers for tu­berculosis patients;

(g) Use of masks; dust control, ventilation and disinfection.

Masks:

They should be thick and cover the nose and mouth completely. They must not be reversed and never reused after dangling around the neck. After use, they can be discarded in a closed contain­ers. Routinely, reusable masks can be disinfected in hot (80°C) water and soap. Some modern masks are also available.

Dust Control:

The disease transmitted by air is mostly by dust and droplet nuclei. The transmission of disease by dust is controlled by treating all floors, window sills and bedding in hospital wards, where the dust accumulates with a film of oil. The dust sticks to the oil and can be easily removed without being disturbed.

The dust control can also be carried out very efficiently by modern vacuum cleaning systems. De­vices that combine with wet scrubbing with vacuum systems are also an excellent means of dust control. Ventilation is very effective method of remov­ing air-borne pathogens.

Disinfection:

Air and dust may be disinfected by irradiation with ultraviolet light, surface disinfec­tion and microbial aerosols. Pathogenic cocci of respiratory tract include staphylococci, streptococci, pneumococci, meningococci. They cause inflammatory process in human beings with the formation of pus. For this reason, they are known as suppurative pyogenic (pyogenic, pyo = pus) cocci. There are several types of symbiosis between cocci and the human body.

Saprophytic and pathogenic types of staphylococci and streptococci live on the skin, mucous membrane and in respiratory tract. Meningococci may harbour for a long period in the nasopharynx. When body resistance is lowered or the skin and mucous membrane are injured, the bacteria penetrate the body tissue and cause infection. The various pathogenic cocci possess different organotropic affinity pneumococci in lungs; meningococci in meningitis, but staphylococci and streptococci have less affinity.