Pathology

• Epidemiology is cause and spread of a disease across a population
• The interaction of social, environmental and microbiological factors causing an infection is epidemiology
• Mycobacterium tuberculosis can't be isolated for diagnostics as it takes too long to culture
• Mycobacterium leprae can't be cultured artificially, and requires an animal to grow
• Treponema pallidum causes syphilis in humans, and was difficult to culture in a lab
• A reservoir of infection is where a microorganism is endemic to and spreads from
• A vehicle of infection is a microorganism carried on an inanimate object like used needles or children's toys
• Clostridium difficile is a bacteria originating endogenously from the microbiota, which can cause bowel perforations from pseudomembranous colitis
• Exogenous transmission can be person to person, such as the faecal oral route, airbourne, sexually transmitted or by animal vectors
• Zoonoses is the transmission of an infection from animal to human
• Vehicles of infection are also known as fomites
• Clostridium tetani releases the tetanus toxin
• Clostridium botulinum releases the botulism toxin
• Staphylococcus aureus releases an enterotoxin causing vomiting
• Endotoxins are released when bacteria lyse, so giving bacteriolytic antibiotics would cause damage
• Bacteria cause symptoms and tissue damage to increase rate of infection
• Endemic is a persistent infection in a certain environment
• Epidemic is a high number of infections in a population
• Pandemic is a country or global wide epidemic
• Iatrogenic spread is when an infection is passed on by medical equipment or lack of sterilisation during a procedure
• Intoxication of bacterial toxins can lead to shock, such as endotoxic shock overstimulating the immune system with endotoxins
• Koch's postulates state that an organism must first be isolated, purified in culture, observed to cause the same disease, then isolated again as the same organism