Fomite transmission of infectious diseases

Fomite Transmission

The purpose of the fomite transmission experiment was to learn modes of pathogen transmission and to identify sites of potential fomite transmission in the environment. Fomite transmission is important to research and understand as with the increase in population around the world as well as mobility of persons, pathogen transmission has become intensified and there are major challenges now when it comes to interrupting the spread of diseases.

For many years it was presumed that infectious diseases were spread mainly via the air or through direct contact with people, and that the surrounding environment played a small or no role at all. Over the years, however, studies have changed the perspective of viral transmission to include a more complex multifactorial model of disease spread. Today there is evidence to support the belief that contaminated fomites or surfaces play a part in the spread of viral infections.

METHODS

Eight areas in the home were located as a potential source of fomite transmission. The eight areas were doorknobs on bathroom doors, doorknobs on front door, the kitchen sink, the bathroom sink, a computer keyboard, the remote control for the television, the telephone, and the kitchen faucet. The type of bacteria expected to be found is staphylococcus, streptococcus, bacillus, Escherichia coli, corynaebacterium, and salmonella.

Two petri dishes were utilized with the bottom of each dish divided into fourths. The quadrants were then labeled #1 through #8. A swab moistened with distilled water was then rubbed vigorously on the first potential fomite in the household (noted above). Quadrant 1 was then inoculated by swabbing the dish with the sterile swab. Caution was used so as not to contaminate any of the other quadrants. The other seven potential fomites were then swabbed and rubbed onto the petri dish in each correlating quadrant. The dishes were then incubated upside down at room temperature for 48 hours. The incubation period can last anywhere from 24 to 72 hours. Evaluation of the petri dishes was then executed. The type of colonies in each quadrant were then noted.

RESULTS

Plate sect / Location ## of types / Description of colony morphologies / Hypothesis supported?

1 Bathroom doorknobs -- form: circular; elevation: raised; margin: entire; surface: shiny; opacity: opaque; chromogenesis: red

2 Front door doorknobs -- form: filamentous; elevation: raised; margin: entire; surface: dull; opacity: opaque; chromogenesis: purple.