Handwashing Lab Report

Renee Sovinski

David Haley

Bio 229.51

Introduction

From the time of birth, microorganisms start to colonize the human body. They will continue to grow until microorganisms outnumber the number of body cells. In fact, the human body contains 100 trillion microorganisms and 10 trillion cells, roughly. Most of the microorganisms on the body are placed in the category called flora. There are two kinds of flora that colonized on the body: transient and normal. Normal flora is considered the “residents” on the human body. Here, they remain in the microbial community, offering benefits and consuming resources. These benefits include aiding with digestion and preventing diseases from pathogens by beating out the competition. In some cases, they may cause opportunistic infections if the person has a weakened immune system or an open wound. Most normal flora is difficult to remove, such as the ones colonised in the skin. These microorganisms are firmly attached to the structures of the skin. Normally, these residents should not be removed because they do not pose any harm and protect the person from invading transient flora.

Microorganisms that are picked up through surface contact are called transients. Transient flora can pose harm to a person because they can transmit disease, if pathogenic. Transients are loosely attached to the superficial layers of the skin which make them relatively easy to remove through handwashing, immune systems or changes in their environment that are less desirable for them.

Handwashing is an effective method of preventing disease or infections acquired by pathogens. With repetitive friction of the epidermis, flora may get stirred up to the surface or may be removed. When performing normal hand washing or rub with hand sanitizer, microorganisms may decrease or increase depending on type of flora present.

This lab experiment illustrates the number of microbial colonies present or absent after performing different methods of handwashing. It compares a control with two variables, regular soap with water and hand sanitizer. Three different colonies were examined in each method to determine if it was normal flora or a transient flora.

Materials

3 NA plates

1 tube sterile saline or water

3 sterile swabs

1 package sterile paper towels

hand sanitizer

Methods

*Students should not disinfect the