B6 Infectious Diseases (2)

Infrastucture damaged and health services disrupted, disease can spread rapidly:

• Damaged sewage systems and water supplies resulting in contaminated drinking water containing disease causing microorganisms lie cholera
• Displacement due to homes destroyed, move into temporary shelter with large numbers of people and poor sanitation, disease spread easily
• Health services disrupted by damaged transport links, infections spreads
• Electricity supplies damaged so food goes off quickly due to broken fridges, lead to increase in food poisoning

Germ theory of disease.

Until 19th century, people didn't understand how diseases caused or spread, believed diseases spontaneously appeared. Pasteur argued there were microbes in the air causing disease and decomposition.

• Heated broth in two flasks, both left open to air, one had a curved neck so bacteria in air would settle in loop and not get to broth
• Broth in flask with curved neck stayed fresh proving it was microbes not air making it go off

First doctor to use antiseptics in surgery:

• When first worked as surgeon, hospital conditions unhygienic, nearly half of patients udnergoing surgery died from wound infections (hospital gangrene/sepsis)
• Observations of wounds led him to think sepsis was type of decomposition, knew about Pasteur's work so he realised he needed to kill microbes getting into wound from air
• Lister started treating and dressing wounds using antiseptic carbolic acid, killed bacteria in wounds and prevented sepsis, techniques taken up by rest of medical profession

Discovered antibiotic penicillin in 1982 by accident:

• Clearing out some plates containing bacteria, noticed one of the plates had mould and area around mould was free of bacteria
• Found mould (Penicillium notatum) produced substance penicillin killing bacteria