Table 3.
Distribution of outbreak reports (2008–16) by the completion of subcomponents for each step in an outbreak investigation, India.
| Steps in an Outbreak Investigation |
Components | Reports showing completion % (N) |
|---|---|---|
| Step 1: Determine existence of an outbreak | Excess of cases | 100% (136) |
| Checking for the background rates of disease | 45% (61) | |
| Changes in surveillance system | 9% (12) | |
| Changes in the population | 9% (12) | |
| Step 2:Confirming the diagnosis | Clinical description of a few cases to raise hypothesis in terms of diagnosis | 97% (132) |
| Collecting the right biologic specimens to confirm the suspected diagnosis | 95% (129) | |
| Safe transport and packaging of biological samples in right laboratory | 25% (34) | |
| Step 3: Define a case | Case definition mentioned | 75% (102) |
| Step 4: Search for cases | Search for cases | 86% (117) |
| Line-listing of cases | 26% (35) | |
| Step 5: Generate hypothesis using descriptive findings | Description of the outbreak by time through an epidemic curve | 62% (84) |
| Spot map to describe the outbreak by place | 32% (43) | |
| Population-based incidence by age and gender | 90% (123) | |
| Conducting hypothesis-generating interviews among case-patients | 69% (94) | |
| Step 6:Test hypothesis with analytical study | Conducting an analytic study | 24% (33) |
| Step 7: Draw conclusions | Analysis of the analytic study | 23% (31) |
| Formulate conclusions that explain facts | 99% (134) | |
| Step 8: Compare hypothesis with established facts | Conducting an environmental/additional investigation to confirm hypothesis | 72% (98) |
| Review of literature | 85% (116) | |
| Discuss conclusions with colleagues, peers and supervisors | 36% (49) | |
| Step 9: Communication of findings | Communication of findings | 65% (88) |
| Step 10: Execute preventive measures | Formulating clear specific recommendations | 93% (126) |
| Relevance and effectiveness of recommendation with implementation | 82% (112) |