To establish an infectious disease, a disease agent (including bacteria, fungi, viruses and protozoa) must first come in contact with a susceptible human host. This phase is called contact or encounter. Humans first encounter with microorganisms starts immediately after birth (period in which the newborn begin to build up its own normal flora) but as […]
Disease transmission & progression Read More »
Bacteriology
Gram staining is a general purpose bacteriological identification technique used in the bacteriology section of the microbiology laboratory to identify and differentiate bacteria into two groups i.e. Gram-positive and Gram-negative. It was discovered by Christian Gram (1853-1938), a Danish scientist in 1884. Christian Gram showed that the cells of some bacteria could be easily decolorized
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Microbe Lab, Bacteriology, Techniques in Microbiology Lab
After exposure to an infectious agent, the body becomes contaminated by the agent, and the pathogenic microorganism eventually develops disease or infection in the susceptible human or animal host following a defined pattern (Figure 1). It is the duty of clinical microbiologists to isolate and characterize the infecting pathogenic microorganism(s), and differentiate same from normal
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Bacteriology
All bacterial cells are extremely infinitesimal (i.e. microscopic), and are never visible to the naked eyes. Bacteria exist in different sizes and shapes which may range from 0.1 µm to 0.3 µm wide and 1 µm to 10 µm in length depending on whether they are rod or spherical in shape (Figure 1). Bacteria occur
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Bacteriology
Microbiota which can also be called normal microflora is the totality of microorganisms that are inherently present in a particular environment, body or location at every specific point of time. Mycoflora are fungal organisms that live in particular sites of the body without causing infection or disease. Microbiota goes into competition with pathogens on and
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Bacteriology, Medical Microbiology
Bacteria (singular: Bacterium) is one of the two important members of the prokaryotes (i.e. cells in which the chromosomes are not separated from the cytoplasmic membrane). The second is Archaea. Bacteria are prokaryotic organisms with very simple cell structure. They are single-celled organisms with complex cell wall. Bacterial cells are the simplest possible forms of
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Bacteriology
Bacillus cereus Gram-positive rods Motile organism Forms endospores Colonies are non-haemolytic on blood agar Aerobic & facultative organism Bacillus anthracis Gram-positive (or Gram-variable) bacillus Non-motile organism Form spores, & are capsulated Aerobic & facultative anaerobe Bacillus stearothermophilus Gram-positive rods Motile organism Forms endospores Aerobic & facultative organism Has the ability to grow at temperatures of
LIST OF SOME BACTERIA OF MEDICAL IMPORTANCE AND THEIR FEATURES Read More »
Bacteriology
Bacteriology is simply defined as the scientific study of bacteria. Pathogenic bacteriology thus, is the scientific study of bacteria that cause diseases in man. This unit which is one of the most important units of the clinical microbiology laboratory handles different types of patient’s specimens, with the sole aim of growing and isolating pathogenic bacteria
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Bacteriology
The human body is inundated with plethora of harmless microorganism’s including fungi and bacteria found in different parts of the body. These organisms which are generally known as normal microflora are found in both the external and internal part of the body. The relationship between indigenous microorganisms of humans (i.e. normal microflora) and the human
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Bacteriology, Medical Microbiology
Microorganisms produce definite patterns on culture media plates as they grow and divide. These specific patterns (inclusive of shapes and sizes) also aid in the preliminary identification of the organisms for further characterization. Colonial morphology is the size, shape, colour, texture and the general structure of an individual colony of a particular microorganism (in this
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Bacteriology, General Microbiology, Microbial Physiology & Metabolism