Influenza Virus: Symptoms, Spread, and Prevention

Influenza: Causes and Terminology

The flu, or influenza, is an infectious disease affecting birds and mammals, caused by an RNA virus belonging to the Orthomyxoviridae family. The word “flu” originates from the French grippe (from Swiss-German groupie, meaning ‘curl’), while “influenza” comes from Italian.

Symptoms in Humans

In humans, influenza primarily affects the airways. Initial symptoms may resemble a common cold but often include systemic signs such as:

  • Fever
  • Sore throat
  • Weakness
  • Muscle pain (myalgia)
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Microbial Control, Immunity, and Human Infections

Sterilization, Disinfection, and Antimicrobial Therapy

This chapter covers the methods used to control microbial growth and the principles governing antibiotic use and resistance.

Key Definitions in Microbial Control

Sterilization
Destroys all microbial life, including spores and viruses.
Disinfection
Removes pathogens from inanimate surfaces (not sterilizing).
Antisepsis
Removes pathogens from living tissues (e.g., skin, mucosa).
Sanitation
Reduces microbe numbers to “safe” levels; not sterilizing.
Cidal
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Meningitis: Causes, Symptoms, Diagnosis, and Treatment Protocols

Meningitis: Etiology, Clinical Features, Diagnosis, and Management

Meningitis is a critical medical condition requiring immediate attention. This document details the etiopathogenesis, clinical features, diagnosis, and management strategies for this inflammation of the meninges.

1. Etiopathogenesis of Meningitis

Meningitis refers to inflammation of the meninges, the protective membranes covering the brain and spinal cord. It may be caused by infectious or non-infectious agents.

Etiology:

  • Infectious causes:

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Microbiology Essentials: Disease Mechanisms and Host Defenses

Chapter 14: Microbial Interactions and Disease Patterns

Differentiating Key Microbiological Terms

  • Etiology/Pathogenesis: Etiology is the study of the cause of a disease, while pathogenesis describes the manner in which a disease develops.
  • Infection/Disease: Infection refers to the colonization of the body by microorganisms, whereas disease is any change in the state of health.

Understanding Symbiotic Relationships

  • Symbiosis: The living together of unlike organisms.
  • Commensalism: One organism benefits,
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Ecosystem Basics: Trophic Levels, Food Webs, and Cycles

Trophic Nutrition and Food Chains

What is Trophic Nutrition?

Trophic nutrition refers to the feeding process or alimentation.

What is a Food Chain?

A food chain describes the feeding relationships between different species.

Why Are Food Chains Not Linear?

Food chains are not linear because some species are consumed by multiple others, connecting with other networks and forming what is called a trophic web (or trophic mesh).

Understanding Trophic Levels

Trophic levels group species based on common food sources,

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Microbe Identification: LPRA, Salmonella, Candida, Haemophilus

Microbacterium Leprae (LPRA)

Identification: Microbacterium leprae causes LPRA (also known as Hansen’s disease). It is an intracellular, pleomorphic bacterium, usually shaped like a stick. It is acid and alcohol resistant, remotely related to Mycobacterium tuberculosis. Histological stains include Ziehl-Neelsen, Fite-Faraco, Munxar, and Sudan III.

Form of Transmission: LPRA is not very infectious. It is transmitted through droplets from the nose and mouth, in frequent and close contact with untreated

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