Sensitivity and Specificity

Sensitivity and Specificity

Sensitivity and Specificity When developing diagnostic tests or evaluating results, it is important to understand how reliable those tests and therefore the results obtained are. By using samples of known disease status, values such as sensitivity and specificity can be calculated that allow its evaluation. Therefore, when evaluating diagnostic tests, it is important to calculate … Read moreSensitivity and Specificity

Biochemical Test of Klebsiella granulomatis

Biochemical Test of Klebsiella granulomatis

Biochemical Test of Klebsiella granulomatis Image: Granuloma inguinale (donovanosis) in a conventional Pap test. A: Granulomatous inflammation is shown with epithelioid histiocytes and lymphocytes. B: The organisms (Donovan bodies) can be seen in thin-walled intracytoplasmic vacuoles (circle ). (Pap stain, Mag ×200 in a and ×400 in b). C: Macrophages show numerous safety pin-shaped structures … Read moreBiochemical Test of Klebsiella granulomatis

Randomized Controlled Trial (RCTs)

Randomized Controlled Trial (RCTs)

Randomized Controlled Trial (RCTs) A randomized controlled trial (or randomized control trial; RCT) is a type of scientific (often medical) experiment that aims to reduce certain sources of bias when testing the effectiveness of new treatments. It is a trial in which subjects are randomly assigned to one of two groups: one (the experimental group) receiving the intervention … Read moreRandomized Controlled Trial (RCTs)

Martin Lewis Agar

Martin Lewis Agar

Introduction Thayer-Martin Agar was developed in 1964 for the isolation of N. gonorrhoeae and N. meningitidis. A further modification of these early formulations was developed to improve the isolation of pathogenic Neisseria sp. from specimens, which contained large amounts of mixed microbial flora. Martin-Lewis Agar is the formulation made after modification which contains an increased … Read moreMartin Lewis Agar

Scope of Epidemiology

Scope of Epidemiology

Scope of Epidemiology Epidemiology is defined as “the study of the distribution and determinants of health-related states or events in specified populations, and application of this study to control of health problems.” Epidemiological studies include observation, surveillance, hypothesis‐testing analytic research methods, and experiments. For many years epidemiology was considered to be restricted to the infectious … Read moreScope of Epidemiology

Epidemiological Markers

Phenotypic and Genetic Markers

Epidemiological Markers Epidemiological markers are biological markers that are used to characterize microorganisms or discriminate between genomes based on the genetic variation among microbial isolates. Uses of Epidemiological Markers Epidemiological markers are mostly used for strain typing. It is used to: Classify isolates of microorganisms Catalogue genetic variation Define relatedness or lack of it between … Read moreEpidemiological Markers

Biochemical Test of Haemophilus parainfluenzae

Biochemical Test of Haemophilus parainfluenzae

Biochemical Test of Haemophilus parainfluenzae Some of the characteristics are as follows: Basic Characteristics Properties (Haemophilus parainfluenzae) Capsule Variable Catalase Variable Gas Variable Gram Staining Gram-negative (-ve) H2S Positive (+ve) Hemolysis Negative (-ve) Indole Variable Motility Negative (-ve) Nitrate Reduction Positive (+ve) Nitrite Reduction Positive (+ve) Oxidase Positive (+ve) Shape Small, pleomorphic rods, usually with … Read moreBiochemical Test of Haemophilus parainfluenzae

Source and Reservoir of Infection

Source and Reservoir of Infection

Source and Reservoir of Infection The starting point for the occurrence of a communicable disease is the existence of a reservoir or source of infection. The source of infection is defined as “the person, animal, object or substance from which an infectious agent passes or is disseminated to the host (immediate source).” The reservoir is … Read moreSource and Reservoir of Infection

Shigella dysenteriae- Pathogenicity and Clinical Manifestation

Shigella dysenteriae- Pathogenicity and Clinical Manifestation

Shigella dysenteriae- Pathogenicity and Clinical Manifestation Shigella dysenteriae is a species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is extremely pathogenic and causes severe dysentery. Infection with this organism often leads to ulceration of the intestinal epithelium. It is known to produce an exotoxin (Shiga toxin) which disrupts protein synthesis and produces endothelial damage. Figure: … Read moreShigella dysenteriae- Pathogenicity and Clinical Manifestation

Data and its types

Data and its types

Data and its types Data is a set of values of subjects with respect to qualitative or quantitative variables. Data is raw, unorganized facts that need to be processed. Data can be something simple and seemingly random and useless until it is organized. When data is processed, organized, structured or presented in a given context … Read moreData and its types