Step 8: Refine Hypotheses and Carry Out Additional Studies If Necessary
If analytical studies do not confirm any of the hypotheses generated by descriptive epidemiology, then you need to go back to the descriptive epidemiology and consider other sources and routes of transmission.
In addition, even if analytical studies establish the source, it may be necessary to pursue the investigation in order to refine your understanding of the source. For example, in the Salmonella outbreak described on page 7 it was clear that the manicotti dish was responsible, but what was the specific source? Was the manicotti prepared at home? Was it purchased? What ingredient was responsible for contaminating the manicotti? Was it the eggs used in preparation of the pasta? Was it the cheese?
Step 9: Implement Control and Prevention Measures
This step is listed toward the end, but, you obviously want to initiate prevention measures as soon as possible if you have identified the source, even if you haven't worked out all of the details.
Step 10: Communicate the Findings
When the investigation is concluded, it is important to communicate your findings to the local health authorities and to those responsible for implementing control and prevention measures. The communications usually require both oral and written reports. The written report should follow standard scientific guidelines, and it should include an introduction, background, methods, results, discussion, and recommendations.