Lab 5: Glo Germ

A brief history of epidemiology

  • Disease was a punishment by the gods for bad behavior.

  • Galen of Pergamon, a Roman physician who lived around 200 AD, influenced Western medicine for nearly 2000 years.

  • One of his theories was that disease was caused by miasma, a poisonous vapor that carried particles of rotting materials.

  • Girolamo Fracastoro proposed that the invisible particles in miasma were living organisms, but until Dutch scientist Anton van Leeuwenhoek invented a microscope, there was no evidence

  • Agostino Bassi proved that a microscopic fungus caused disease in silkworms.

  • Ignaz Semmelweis reduced deaths in his hospital in Vienna when he required that physicians wash their hands in chlorinated lime solutions

  • Louis Pasteur published a paper in which he explained that microorganisms caused spoilage and fermentation in foods

  • Joseph Lister read Pasteur’s work and used carbolic acid solutions to prevent infection in surgical incisions.

  • Robert Koch succeeded in isolating the bacterium that caused anthrax

EPIDEMIOLOGY - is defined as the study of the causes, distribution, and control of disease in a population.

  • Dr. John Snow is called the father of epidemiology; traced the source of a cholera epidemic in London by placing a dot on a map of the afflicted area for each person who had contracted the disease. The dots clustered around a public water pump. A check of the water company revealed that the water source for that pump was a polluted section of the Thames River.

The Centers for Disease Control and Prevention (CDC), part of the Department of Health and Human Services, coordinates epidemiology in the United States.

Purpose:

  • importance of effective hand washing to minimize direct person-to-person transmission of pathogens by health-care professionals and food handlers.

  • critical to laboratories handling pathogens to minimize transmission

Materials:

One Ultraviolet pen light

One bottle of Glo Germ™ Lotion-based simulated germs

paper towels

hand soap

washable markers

hand-sanitizer gel

Instructions:

Shake the bottle of Glo-Germ lotion well.

Have your partner apply 2–3 drops of gel on the palms of both of your hands.

Rub your hands together, thoroughly covering your hand surfaces, including the backs and between the fingers. Be sure to cover hands completely, particularly under nails, around cuticles and between fingers. Wipe off excess with paper towel.

Hands covered with Glo Germ prior to washing

Have your lab partner shine the UV light on your hands to view “glowing germs” that exist before hand washing. Demonstration works best in a darkened room. Do not handle the light yourself because you will contaminate it with the artificial germs.

Have your lab partner turn on warm water at a sink for you. Then wash your hands with soap and warm water as thoroughly as you can for at least 20 seconds. When you are finished, have your lab partner turn off the water and hand you a fresh paper towel. Dry your hands.

Have your partner shine the UV light on your hands once more. Examine the hand surfaces contaminated by the artificial germs.