Survey of Nasal Carriage of Staphylococcus aureus
Order Description
Survey of Nasal Carriage of Staphylococcus aureus
Report Format
? Naming bacteria – you should use the full name of the organism when you first mention it in the report, thereafter you may use the abbreviated form S. aureus ?Please ensure that the organism name is written in italics ?Ensure that the organism name is written correctly in standard scientific format -capital ‘S’ for the genus name and small letter ‘a’ for the species ?When referring to the selective agar use the full name when first mentioned thereafter you may refer to MSA.
Aim/Introduction
Aim ?What is the purpose of this exercise? ?Introduction ?Why is S. aureus an important pathogen? ?Give a brief summary of the pathogenicity mechanisms ?Significance of carriage of S. aureus in ?Hospital patients, pre operative patients ?Hospital staff ?Food handlers
Materials and Methods
S. aureus produces an opaque colony surrounded by a yellow zone on MSA. Why? ?Confirmation tests. ?Gram stain on suspect colonies. ?Colonies identified as gram positive cocci were tested- ?Catalase test ?Streaked to NA or HBA ?Slide coagulase test (see note in discussion section) ?S. aureus colonies were confirmed after discussion with your demonstrator
Results
?Acceptance Criteria – this needs to be stated in results section. Colonies were deemed to be S.aureus if they were: ?Mannitol positive, typical colonial morphology on MSA ?Gram positive cocci with typical microscopic morphology ?Catalase positive ?Slide coagulase positive
?Acceptance Criteria cont.– A student was deemed to be a carrier of S. aureus for the purpose of our study if one or more typical and confirmed colonies were present on their MSA plate
Data from 2011-2015 (RMIT Microbiology 1 students) ? Note: we do not require comments on individual results – you should only use the collective data in this table.
Year Bundoora Campus City Campus
Number positive students Total number students tested Number positive students Total number students tested
2011 14 80 32 140
2012 40 104 47 135
2013 36 96 39 110
2014 33 115 26 135
2015 18 77 33 113
Discussion
?You need to refer to the journal articles you have collected on this topic. ? Undergraduates -You need to have include at least two studies (one in the last 10 years) that have investigated the Nasal Carriage of S. aureus in “normal or general” population. ?You can use more than 2 articles ?Compare the carriage rate obtained in our study with the rates obtained in these studies.
?Points for comparison ? Number of people surveyed ? Test Methodology: ?Swab technique ?Initial recovery medium ?Confirmation techniques ?Were our results in the expected range? ?What physical conditions or environmental factors might influence nasal carriage rate?
?Any comments on the methodology of our study that may have influenced the results? ?Suspect colonies that were present only in the primarily streak ie were not well isolated could not be confirmed. ?Each student swabbed their own nose – swab method was not standardized ?We used the slide coagulase test not the tube method ?How would these factors influence the results. Can you think of any other variables
References
All information used in the report (other than your own observations) must be referenced. ?This includes class results. (Anderson J. 2015 personal communication) ?Cite references by the APA or Havard system ?The RMIT library has a brief 3 page summary on each system ?In the reference section list references in order alphabetical order ?Author(s) (you must include all authors here), Year, Title, Journal, volume, pages (The main author et al and the year is permitted in the text) ?Refer to Appendix 1 for referencing internet sources
?Note – only reputable peer reviewed references will be accepted- no wikipedia ?Journal articles can be found on the ASM website. eg J. Clinical Microbiology ?You may need to search this site through the RMIT library as they subscribe to ASM. ?You can also refer to textbooks