Technical Guidelines for Integrated Disease Surveillance ... - PHRplus

1. If data from previous years is available, review trends in cases and deaths due to these diseases overthe last five years. Determine a baseline number to describe the current extent of the disease in thecatchment area.2. As appropriate, take into account factors for diseases with seasonal increases, such as malaria orcholera.3. State the threshold clearly as a number of cases per month or week, so that health staff responsible forsurveillance activities can readily recognise when the threshold is reached.4. Periodically revise the epidemic threshold and adjust it according to past and current trends for thedisease. If the extent of the disease’s burden is changing (for example, cases are increasing), thenadjust the threshold.Alert and action thresholds are described in Section 3.3.3. Thresholds recommended by Ghana’s MOH/GHSfor taking action to implement interventions or investigations of a case or outbreaks are in Section 9 of theseguidelines.4.2 Record reported outbreaks and rumoursTracking reported outbreaks ensures that the report of each suspected outbreak or rumour of outbreak isfollowed by some action and resolution. Keeping this record also contributes to later evaluation of the timelinessand completeness of the outbreak investigation and response process. A sample form for tracking reports ofoutbreaks is in Annex 20.4.3 Verify the reported outbreakPromptly verify reports of outbreaks received from health facilities or through community rumour. This isimportant to ensure that timely decisions are made and to prevent expending resources on investigating eventsthat are not true outbreaks.To verify a reported outbreak, consider the following factors:Source of information (Is the source of the rumour reliable? Is the report from a health facility?)Severity of illnessNumber of reported cases and deathsTransmission mode and risk for wider transmissionPolitical or geographic considerationsPublic relationsAvailable resourcesThe circumstances of a particular outbreak may cause the district to treat the investigation with moreurgency than the above factors imply. For example, reports of a suspected case of viral haemorrhagic fever aretreated with more urgency than a report of a neonatal tetanus case because the risk for wider transmission of thefever is greater. Regardless of the factors, health facilities must report suspected outbreaks (including immediatelynotifiable cases) within 48 hours.Section 4: Investigate Reported Outbreaks and other Public Health Events45