Author name: sciencevivid

Introduction to Prions: When a misfolded prion enters a healthy organism, it causes already-existing, correctly folded proteins to transform into the form of a misfolded prion. Therefore, other normal proteins misfold into prion form using prions as a template. Prion disorders, also known as transmissible spongiform encephalopathies, are a class of neurodegenerative illnesses that are […]

Introduction to Fasciola hepatica: Fasciola hepatica is a hermaphroditic trematode with a complex life-cycle that includes an intermediate (snail) and definitive (mammalian) host. The earliest known trematode or fluke was F. hepatica.  However, it was initially found in sheep rather in humans. The disease, known as liver rot, is brought on by consuming metacercaria from

Introduction to Dengue Virus: Dengue is a mosquito-borne disease caused by the skin inoculation any of four antigenically different serotypes of the Dengue virus (DENV 1-4), characterized by wide spectrum of illness ranging from asymptomatic to severe forms. As the name ‘breakbone fever’, the patient complains of pain in the back, joint, muscles and the

General Considerations in Specimen Collection The vitals for specimen collection: Requisition The following details should be included in the laboratory request, or “lab slip”: Specimen selection and Collection: Timing of Specimen Collection: Transport of Clinical Specimens: Storage Guidelines for Different Specimen Types: Criteria for Specimen Rejection: SPECIMEN SELECTION POSSIBLE BACTERIA COLLECTION EQUIPMENT TRANSPORT Wounds, Abscesses

Introduction to Shigella: Shigella are the cause of bacillary dystentery exclusively facultative intracellular pathogens in intestine of humans and other primates. Shigella are slender (1-3 × 0.5 µm in size) Gram-negative rods belonging to the family Enterobacteriaceae. They are non-motile bacterium, non–sporulating and non-capsule formers. The genus Shigella comprises four different species; S. dysenteriae, S.flexneri,

Selection of Stool Samples: Collection of Stool Samples: Principles of Proper Sample Collection Recommended Materials and Precautions Preservation of Stool Samples: Principle and Importance of Preservation Types of Preservatives and Their Uses: Schaudinn’s Fixative Advantages Disadvantages PVA (Polyvinyl Alcohol) Advantages Disadvantages MIF (Merthiolate-Iodine-Formalin) Advantages Disadvantages Diluted Formalin Advantages Disadvantage

Macroscopy of Clinical Specimens: Sputum Examination Stool Macroscopy Urine Examination Cerebrospinal fluid (CSF) Microscopic Examination: Sputum Microscopy Pus, ulcer and skin specimen microscopy  Before utilizing the swab to create gram smears, the culture media should be inoculated. Feces microscopy Urine microscopy Cerebrospinal Fluid (CSF) Microscopy Purulent or cloudy CSF Slightly cloudy or clear CSF Upper

General characteristics: Classification: Test Classical EL Tor Hemolysis -ve +ve VP Test -ve +ve Polymyxin sensitivity Sensitive Resistant Group IV phage susceptibility Susceptible Non-susceptible Chicken Erythrocyte agglutination -ve +ve Mode of transmission:  Infection is acquired by feco-oral route and by ingestion of improperly cooked shellfish. The incubation period ranges from few hours to 2-3 days.

Diagnosis of Vibrio cholerae Culture methods: Fig: Vibrio cholerae on TCBS Biochemical identification: Test V. cholerae KIA (Kligler’s Iron Agar)  K/A TSI (Triple Sugar Iron) A/A String + Oxidase + Gas from glucose – Sucrose + Lysine + Arginine – Ornithine + VP (Voges-Proskauer ) V Growth in 0% NaCl + Growth in 1% NaCl